Protease inhibitors

The present invention provides compounds of formula (I) which inhibit proteases, including cathepsin K, pharmaceutical compositions of such compounds, and methods for treating diseases of excessive bone loss or cartilage or matrix degradation, including osteoporosis; gingival disease including gingivitis and periodontitis; arthritis, more specifically, osteoarthritis and rheumatoid arthritis; Paget's disease; hypercalcemia or malignancy; and metabolic bone disease therewith.

EXAMPLES In the following synthetic examples, temperature is in degrees Centigrade (°C.). Unless otherwise indicated, all of the starting materials were obtained from commercial sources. Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. These Examples are given to illustrate the invention, not to limit its scope. Reference is made to the claims for what is reserved to the inventors hereunder. 
 Example 1 
 Preparation of N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) cis-2,6-dimethyl-4-morpholino-N-benzoylthiourea Cis-2,6-dimethylmorpholine (1.40 g, 12.17 mmol, 1.5 mL) was dissolved in chloroform (20 mL) and benzoyl isothiocyanate (2.0 g, 12.17 mmol, 1.75 mL) was added. After stirring 45 minutes at room temperature, the solution was concentrated to giv the title compound as a yellow solid (3.94 g, 100%). MS (ESI): 279.2 (M&plus;H) &plus; . 
 b) cis-2,6dimethyl-4-morpholinothiourea The compound of Example 1(a) (3.38 g, 12.17 mmol) was dissolved in methanol (40 mL) and water (40 mL), potassium carbonate (8.4 g, 60.84 mmol) was added and the solution was heated at reflux overnight. The reaction mixture was concentrated, redissolved in ethyl acetate, washed with sodium bicarbonate and water, then dried (MgSO 4 ), filtered and concentrated to afford the title compound as a beige solid (1.7 g, 80%). MS (ESI): 174.9 (M&plus;H) &plus; . 
 c) ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate The compound of Example 1(b) (1.7 g, 9.74 mmol) was dissolved in ethanol (25 mL) upon heating. The solution was cooled to room temperature and ethylbromopyruvate (1.22 mL, 9.74 mmol) was added. The reaction mixture was heated at reflux for 10 minutes, then concentrated. The residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate. The aqueous phase was extracted with ethyl acetate and the combined organic phases were washed with saturated brine, dried (MgSO 4 ), filtered and concentrated to an orange oil. The crude product was passed trough silica gel eluting with ethyl acetate/hexane (1:8, then 1:3) to give the title compound as a yellow solid (2.07 g, 79%). MS (ESI): 271.3 (M&plus;H) &plus; . 
 d) N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide The compound of Example 1(c) (2.07 g, 7.65 mmol) was dissolved in ethanol (25 mL) and hydrazine monohydrate (3.7 mL, 76.56 mmol) was added. The solution was heated at reflux for 2 hours, then concentrated to afford the title compound as an orange solid (1.96 g, 100%). MS (ESI): 257.2 (M&plus;H) &plus; . 
 e) a-isocyanato-L-leucine Methyl Ester L-leucine methyl ester hydrochloride (25 g, 0.14 mol) was dissolved in methylene chloride (450 mL), cooled to 0° C., and pyridine (43.5 g, 0.55 mol, 44.5 mL) was added, then a 1.93 M solution of phosgene in toluene (0.18 mol, 92.7 ml) was added slowly. After stirring at 0° C. for 2 h, the mixture was poured into 0.5 N HCl (1400 mL) and ice (900 mL). The organic layer was washed with 0.5 N HCl (1400 mL) and ice (900 mL). The aqueous layers were extracted with methylene chloride (450 mL) and the combined organic layers were washed with saturated brine (1400 mL) and ice (900 mL), then dried (MgSO 4 ), filtered and concentrated. The residue was distilled (56-58° C.; 0.78 mmHg) to provide the title compound as a colorless liquid (20.4 g, 86%). 1 H NMR (250 MHz, CDCl 3 ) d 4.04 (dd, 1H), 3.82 (s, 3H), 1.92-1.72 (m, 1H), 1.69-1.62 (m, 2H), 0.96 (d, 3H), 0.94 (d, 3H). 
 f) N-(4-pyridinylmethoxycarbonyl)-L-leucine Methyl Ester A solution of the compound of Example 1(e) (5.10 g, 29.8 mmol) and 4-pyridylcarbinol (3.25 g, 29.8 mmol) in toluene (30 mL) was heated at reflux for 24 h. The solution was concentrated and the residue was purified by flash chromatography on 250 g of 230-400 mesh silica gel, eluting with 3:1 ethyl acetate/hexanes, to give the title compound (7.86 g, 94%). 1 H NMR (250 MHz, CDCl 3 ) d 8.59 (d, 2H), 7.24 (d, 2H), 5.33 (d, 1H), 5.13 (s, 3H), 4.40 (dt, 1H), 3.75 (s, 3H), 1.81-1.51 (m, 3H), 0.96 (d, 3H), 0.95 (d, 3H). 
 g) N-(4-pyridinylmethoxycarbonyl)-L-leucine To a stirring solution the compound of Example 1(f) (1.98 g, 7.06 mmol) in THF (7 mL) was added 7 mL of water followed by LiOH.H 2 O (325 mg, 7.76 mmol). The mixture was stirred for 30 minutes and then concentrated. The residue was redissolved in water (10 mL) and 3 N HCl was added (2.6 mL). The solution was lyophilized to yield a white solid (2.015 g, 6.44 nmuol). MS (ESI): 267.2 (M&plus;H) &plus; . 
 h) N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide To a stirring solution of the compound of Example 1(g) (104 mg, 0.39 mmol) in DMF (2.5 mL) was added the compound of Example 1(d) (100 mg, 0.39 mmol), 1-hydroxybenzotriazole (9.5 mg, 0.07 mmol), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (100 mg, 0.39 mmol). After stirring at room temperature for 16 h, the solution was partitioned between ethyl acetate and water. The aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with saturated brine, dried (MgSO 4 ), filtered and concentrated. The crude product was purified by column chromatography on silica gel (6% methanol in methylene chloride) to afford the title compound as a white solid (125 mg, 51%). MS (ESI): 505.4 (M&plus;H) &plus; . 
 Example 2 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropylmethyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-cyclopropylmethyl Isobutyramide Triethylamine (1.53 g, 15.09 mmol, 2.1 mL) and isobutylamine (1.10 g, 15.09 mmol, 1.5 mL) were dissolved in methylene chloride (15 mL), cooled to 0° C., and cyclopropane carbonyl chloride (1.58 g, 15.09 mmol, 1.4 mL) was added dropwise. After stirring at 0° C. for one hour the mixture was diluted with methylene chloride (60 mL) and washed with NaOH (1M), then with saturated brine, dried (MgSO 4 ), filtered and concentrated. The residue was washed with ether and dried to give the title compound as a beige solid (2.1 g, 100%). MS (ESI): 141.9 (M&plus;H) &plus; . 
 b) N-cyclopropylmethyl Isobutylamine To a stirring solution of 1M LiAlH 4 in THF (11.3 mL, 11.3 mmol), cooled to 0° C., was added slowly over 20 minutes a solution of the the compound of Example 2(a) (1.595 g, 11.3 mmol) in THF (20 mL). After the addition was complete, the ice bath was removed and the solution was heated at 55° C. for 30 minutes. The mixture was cooled to 0° C. and quenched with water (0.43 mL) and 15% aqueous NaOH (0.43 mL) and water (1.29 mL). The solid was removed by filtration and washed with ether, dried (MgSO 4 ) and filtered. The filtrate was evaporated to dryness to give the title compound as a a colorless liquid (1.15 g, 80%). MS (ESI): 128.0 (M&plus;H) &plus; . 
 c) N-&lsqb;2-&lsqb;N-cyclopropylmethyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl isobutylamine for cis-2,6-dimethylmorpholine in step (a), the title compound was prepared as a yellow solid (60 mg, 31%). MS (ESI): 517.3 (M&plus;H) &plus; . 
 Example 3 
 Preparation of N-&lsqb;2-(4-methyl-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) ethyl 2-aminothiazole-4-carboxylate Hydrobromide To a stirring suspension of thiourea (46.7 g, 0.614 mol) in EtOH (640 mL) was added ethyl bromopyruvate (120 g, 0.614 mol, 77.2 mL) slowly. After stirring at 45° C. for 16 h the solution was cooled to room temperature and placed in the refrigerator overnight. The mixture was filtered, the crystals were washed with cold ethanol and air dried to give the product as pale yellow crystals (132.74 g, 85%). MS (ESI): 172.9 (M&plus;H) &plus; . 
 b) 2-bromothiazole-4-carboxylic Acid To a stirring suspension of the compound of Example 3(a) (32.11 g, 0.127 mol) in 16% HBr (aq) (400 mL) at 0° C. a solution of NaNO 2 (9.11 g, 0.132 mol) in water (16 mL) was added. After stirring for 35 min, CuBr (20.6 g, 0.144 mol) was added followed by additional 16% Hbr(aq) (150 mL). The mixture was heated at 70° C. for 1 h and immediately filtered. The filtrate was saturated with NaCl and extracted with ethyl acetate (2×500 mL). The organic phases were combined, dried (MgSO 4 ), filtered and concentrated to a brown solid. This was combined with solid collected by filtration and used without further purification or characterization in the next step. 
 c) ethyl 2-bromothiazole-4-carboxylate The compound of Example 1(b) was heated at reflux in EtOH (1 L) for 1 h, then filtered. To the filtrate was added 64 drops of 48% (aq) HBr. After stirring at reflux for 24 h the solution was concentrated and redissolved in EtOAc (1 L). The solution was washed successively with saturated aqueous NaHCO 3 (1 L) and brine (1 L), dried (MgSO 4 ), filtered, decolorized with charcoal, filtered through Celite, and concentrated to a pale yellow solid (16.95 g, 56%). 1 H NMR (400 MHz, CDCl 3 ) d 8.14 (s, 1H), 4.46, (q, 2H), 1.43 (t, 3H). 
 d) 4-methyl-L-naphthalene Boronic Acid To a stirring solution of 1-bromo-4-methylnaphthalene (1.0 g, 4.52 mmol) in THF (5 mL) at −78° C. was added N-butyllithium (1.8 mL, 4.52 mrnol, 2.5M in hexane) dropwise. After stirring at −78° C. for 1 h, triisopropylborate (4.52 g, 22.6 mmol) was added. After stirring at room temperature for 3 h, the solution was partitioned between 3N HCl and ethyl acetate. The organic phase was washed successively with saturated aqueous NaHCO 3 and brine, then dried (MgSO 4 ), filtered and concentrated to a yellow solid which was washed with hexane to yield the title compound as a pale yellow solid (0.5 g, 59%). 1 H NMR (400 MHz, CDCl 3 ) d 9.35 (d, 1H), 8.58 (d, 1H), 8.14 (d, 1H), 7.64 (m, 2H), 7.54 (d, 1H), 2.82, (s, 3H). 
 e) ethyl 2-(4-methyl-1-naphthyl)thiazol-4-carboxylate To a stirring mixture of the compound of Example 1(c) (0.30 g, 1.27 mmol), the compound of Example 1(d) (0.355 g, 1.91 mmol), and Pd(Ph 3 P) 4 (0.059 g, 0.05 mmol)) in EtOH (4 mL) and toluene (4 mL) was added NaHCO 3 (4.42 mL, 1.0 M in water). After stirring at reflux for 4 h,the mixture was cooled and partitioned between 1 N HCl (25 mL) and ethyl acetate (25 mL). The organic layer was washed with brine, dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a foamy solid. (0.257 g, 68%). MS (ESI): 298.2 (M&plus;H) &plus; . 
 f) N-&lsqb;2-(4-methyl-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(d), except substituting ethyl 2-(4-methyl-1-naphthyl)thiazole-4-carboxylate for ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate, the title compound was prepared as a pale yellow solid (0.245 g, 100%). MS (ESI): 284.2 (M&plus;H) &plus; . 
 g) N-&lsqb;2-(4-methyl-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(e)-1(h), except N-&lsqb;2-(4-methyl-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide in step (h), the title compound was prepared as a white solid (0.122 g, 48%). MS (ESI): 532.1 (M&plus;H) &plus; . 
 Example 4 
 Preparation of N-&lsqb;2-&lsqb;N-methyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-(4-pyridinylmethoxycarbonyl)-L-leucine tert-butyl Ester Following the procedure of Example 1(e)-1(f), except substituting L-leucine tert-butyl ester hydrochloride for L-leucine methyl ester hydrochloride in step (e), the title compound was prepared as a colorless oil (2.945 g, 64%). MS (ESI): 323.4 (M&plus;H) &plus; . 
 b) N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine Tertbutoxycarbonyl Ester The compound of Example 3(a) (2.9 g, 8.99 mmol ) was dissolved in THF (40 mL) and methyl iodide (2.24 mL , 35.98 mmol) was added. The reaction mixture was cooled to 0° C. in a flask protected from moisture. Sodium hydride dispersion (1.214 mg, 13.49 mmol) was added cautiously and the suspension was stirred for 5 h at room temperature. Ethyl acetate was then added (to consume the sodium hydroxide formed from the excess of sodium hydride), followed by water, dropwise, to destroy the excess of sodium hydride. The solution was concentrated in vacuo, and the oily residue partitioned between ether and water. The ether layer was washed with saturated aqueous sodium bicarbonate. The product was extracted with ethyl acetate, the extract was washed with water, dried (MgSO 4 ), filtered and concentrated. The crude product was purified by column chromatography on silica gel (ethyl acetate/hexane, 3:1) to give a yellow oil (2.07 mg, 68%). MS (ESI): 337.5 (M&plus;H) &plus; . 
 c) N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine To the compound of Example 3(b) (2.07 g, 6.15 mmol) in methylene chloride (20 mL) was added trifluoroacetic acid (3 mL). After stirring one hour at room temperature the solution was concentrated and the residue was redissolved in methylene chloride, washed with saturated aqueous sodium bicarbonate, dried (MgSO 4 ) and concentrated to afford the title compound as a white solid (1.72 g, 100%). MS (ESI): 281.3 (M&plus;H) &plus; . 
 d) N-&lsqb;2-&lsqb;-methyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-methyl isobutylamine for cis-2,6-dimethylmorpholine in step (a), and N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a pale yellow solid (91.8 mg; 43%). MS (ESI): 491.3 (M&plus;H) &plus; . 
 Example 5 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-(3-pyridinylmethoxycarbonyl)-L-leucine Following the procedure of Example 1(f)-1(g), except substituting 3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid. MS (ESI): 267.2 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-(3-pyridinylmethoxycarbonyl)-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.029 g, 28%). MS (ESI): 518.2 (M&plus;H) &plus; . 
 Example 6 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′N-&lsqb;N-2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 5(a)-5(b), except substituting 2-pyridylcarbinol for 3-pyridylcarbinol in step (a), the title compound was prepared as a white solid (0.084 g, 82%). MS (ESI): 518.2 (M&plus;H) &plus; . 
 Example 7 
 Preparation of N-&lsqb;2-(5-acenaphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 3(a)-3(g), except substituting 5-bromoacenaphthene for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as a white solid (0.166 g, 74%). MS (ESI): 544.2 (M&plus;H) &plus; . 
 Example 8 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropylmethyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 2(a)-2(c), except substituting N-Methyl-N-(4pyridinylmethoxycarbonyl)-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (c), the title compound was prepared as a yellow solid (50 mg, 25%). MS (ESI): 531.3 (M&plus;H) &plus; . 
 Example 9 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-cyclopropylmethyl Cyclopropylamine Cyclopropylamine (1.14 g, 20.0 mmol, 1.4 mL) and cyclopropanecarboxaldehyde (1.40 g, 20.0 mmol, 1.5 mL) were dissolved in methylene chloride (10 mL) and stirred at room temperature. After two hours, the solution was dried (MgSO 4 ), and concentrated to afford the pure imine. The compound was dissolved in ether (10 mL), the solution was cooled to 0° C. and lithium aluminum hydride (30 mL, 30 mmol, 1 M in ether) was added slowly. The solution was stirred for two hours and then quenched at 0° C. with water (1.14 mL), 15% sodium hydroxyde (1.14 mL), water (3.42 mL). The solid was removed by filtration and washed with ether. The filtrate was dried (MgSO 4 ), filtered and concentrated to afford a colorless liquid (1.58 g, 71%). MS (ESI): 111.9 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a), the title compound was prepared as a white solid (165 mg, 88% yield). MS (ESI): 501.4 (M&plus;H) &plus; . 
 Example 10 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropylmethyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 2(a)-2(c), except substituting N-(3-pyridinylmethoxycarbonyl)-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (c), the title compound was prepared as a yellow solid (154 mg, 89%). MS (ESI): 517.4 (M&plus;H) &plus; . 
 Example 11 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropylmethyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 2(a)-2(c), except substituting N-(2-pyridinylmethoxycarbonyl)-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (c), the title compound was prepared as a yellow solid (100 mg, 65%). MS (ESI): 517.3 (M&plus;H) &plus; . 
 Example 12 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropylmethyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(3-p2pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 4(a)-4(d), except substituting 3-pyridylcarbinol for 4-pyridylcarbinol in step (a) and N-cyclopropylmethyl isobutylamine for N-methyl isobutylamine in step (d), the title compound was prepared as a yellow solid (30 mg, 22%). MS (ESI): 531.4 (M&plus;H) &plus; . 
 Example 13 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and 3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (85 mg, 43%). MS (ESI): 501.4 (M&plus;H) &plus; . 
 Example 14 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 4(a)-4(d), except substituting N-cyclopropylmethyl cyclopropylamine for N-methyl isobutylamine in step (d), the title compound was prepared as a white solid (58 mg, 35%). MS (ESI): 515.3 (M&plus;H) &plus; . 
 Example 15 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1 (h), except substituting diisobutylamine for cis-2,6-dimethylmorpholine in step (a) and 2-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a yellow solid (140 mg, 77%). MS (ESI): 519.4 (M&plus;H) &plus; . 
 Example 16 
 Preparation of N-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-&lsqb;1-(1,2,3,4-tetrahydroquinolino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting 1,2,3,4-tetrahydroquinoline for cis-2,6-dimethylmorpholine in step (a), the title compound was prepared as a yellow solid (168 mg, 88%). MS (ESI): 523.4 (M&plus;H) &plus; . 
 Example 17 
 Preparation of N-&lsqb;4-methyl-2-(3-phenoxy)phenylpentanoyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 2-(3-phenoxyphenyl)-4-methylpent-4-enoic Acid To a stirring solution of diisopropylamine (4.99 g, 49.3 mmol) in THF (50 mL) cooled to −78° C. was added n-butyllithium (19.4 mL, 48.5 mmol, 2.5M in hexane) dropwise. After stirring for 15 min at −78° C., a solution of 3-phenoxyphenylacetic acid (5.0 g, 21.9 mmol) in THF (20 mL) was added dropwise. The mixture was warmed to 0° C. then cooled to −78° C. and 3-bromo-2-methylpropene (4.4 g, 32.9 mmol) was added to the mixture in one portion. After stirring at −78° C. for 2 h, the reaction was quenched with 10 mL of water then concentrated. The residue was redissolved in water and extracted with ether (200 mL). The aqueous layer was acidified (3 N HCl) and extracted with ether (2×200 mL). The organic layers were combined, dried (MgSO 4 ), filtered and concentrated to yield the title compound as a white solid (5.4 g, 87%). 1H NMR (400 MHz, CDCl 3 ) d 7.36 (m, 3H), 7.14 (m, 2H), 7.01 (m, 4H), 4.78 (d, 2H), 3.82 (t, 1H), 2.83 (dd, 1H), 2.47 (dd, 1H), 1.75 (s, 3H). 
 b) 2-(3-phenoxyphenyl)-4-methylpentanoic Acid To a stirring solution of the compound of Example 17(a) (5.4 g, 19.1 mmol) in ethyl acetate (75 mL) was added palladium on carbon (2.0 g). After stirring under a balloon of hydrogen for 16 h, the mixture was filtered through celite. The filtrate was concentrated and the residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a white solid (2.1 g, 39%). MS (ESI): 283.2 (M−H) − . 
 c) (±)-N-&lsqb;4-methyl-2-(3-phenoxy)phenylpentanoyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting 2-(1-naphthyl)thiazol-4-ylcarbonylhydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and 2-(3-phenoxyphenyl)-4-methylpentanoic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (0.246 g, 82%). MS (ESI): 536.2 (M&plus;H) &plus; . 
 Example 18 
 Preparation of N-&lsqb;2-&lsqb;N-methyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-′-&lsqb;-4-methyl-2-(3-phenyl)phenylpent-4-enoyl&rsqb;hydrazide 
 a) 2-(3-phenylphenyl)-4-methylpent-4-enoic Acid Following the procedure of Example 17(a), except substituting 3-biphenylacetic acid for 3-phenoxyacetic acid, the title compound was prepared as a white solid. MS (ESI): 265.3 (M−H) − . 
 b) N-&lsqb;2-&lsqb;N-methyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;-4-methyl-2-(3-phenyl)phenylpent-4enoyl&rsqb;hydrazide Following the procedure of Example 1(a)-(1(h), except substituting N-methyl isobutylamine for cis-2,6-dimethylmorpholine in step (a), and 2-(3-phenylphenyl-4-methylpent-4-enoic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid. MS (ESI): 477.3 (M&plus;H) &plus; . 
 Example 19 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting diisobutylamine for cis-2,6-dimethylmorpholine in step (a) and 3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a yellow solid (110 mg, 30%). MS (ESI): 519.4 (M&plus;H) &plus; . 
 Example 20 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 4(a)-4(d), except substituting 3-pyridylcarbinol for 4-pyridylcarbinol in step (a) and N-cyclopropylmethyl cyclopropylamine for N-methyl isobutylamine in step (d), the title compound was prepared as a yellow solid (33 mg, 25%). MS (ESI): 515.4 (M&plus;H) &plus; . 
 Example 21 
 Preparation of N-&lsqb;2-(N-cyclopropylmethyl-N-propylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropyl propylamine for cis-2,6-dimethylmorpholine in step (a) and 3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a yellow solid (40 mg, 25%). MS (ESI): 503.3 (M&plus;H) &plus; . 
 Example 22 
 Preparation of N-&lsqb;2-&lsqb;N-methyl-N-(2-methoxypropylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;4-methyl-2-(3-phenyl)phenylpentanoyl&rsqb;hydrazide 
 a) 2-3-phenylphenyl)-4-methylpentanoic Acid Following the procedure of Example 17(a)-17(b), except substituting 3-biphenylacetic acid for 3-phenoxyacetic acid, the title compound was prepared as a white solid. MS (ESI): 267.4 (M−H) − . 
 b) N-&lsqb;2-&lsqb;N-methyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;4-methyl-2-(3-phenyl)phenylpentanoyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-methyl isobutylamine for cis-2,6-dimethylmorpholine in step (a), and 2-(3-phenylphenyl)-4-methylpentanoic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (185 mg, 88%). MS (ESI): 479.4 (M&plus;H) &plus; . 
 Example 23 
 Preparation of N-&lsqb;N-(2-methylpropyl)-N-(3-phenylphenyl)carbamoyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 3-phenylaniline To a stirring solution of 3-nitrobiphenyl (1.2 g, 6.0 mmol) in ethyl acetate (25 mL) was added 10% Palladium on carbon (500 mg, 40% w/w). After stirring under a balloon of hydrogen for 24 h, the mixture was filtered through Celite and concentrated to yield the title compound as a white solid (0.956 g, 94%). MS (ESI): 170.0 (M&plus;H) &plus; . 
 b) N-(3-phenyl)phenyl Isobutylamine Following the procedure of Example 2(a)-2(b), except substituting 3-phenylaniline for isobutylamine, and isobutyryl chloride for cyclopropane carbonyl chloride in step (a), the title compound was prepared as a brown oil (1.1 g, 90%). MS (ESI): 226.1 (M&plus;H) &plus; . 
 c) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;&lsqb;N-isobutyl-N-(3-biphenyl)&rsqb;amido&rsqb;hydrazine To a solution of phosgene (0.289 mL, 1.93M in toluene) was added a mixture of the compound of Example 23(b) (0.126 g, 0.558 mmol) and N-methylmorpholine (0.056 g, 0.55 8 mmol) in dichloromethane (3 mL) dropwise. After stirring for 20 min., 2-(1-naphthyl)thiazol-4-ylcarbonylhydrazide (0.150 g, 0.558 mmol) and N-methylmorpholine (0.056 g, 0.558 mmol) in dichloromethane (3 mL) was added followed by DMF (3 mL). After stirring at 50° C. for 16 h, the solution was diluted with ethyl acetate and washed successively with water, saturated aqueous sodium bicarbonate, and brine. The organic layer was, dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a white solid (0.122 g, 42%). MS (ESI): 521.3 (M&plus;H) &plus; . 
 Example 24 
 Preparation of N-&lsqb;4-methyl-2-(3-phenyl)phenylpentanoyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and 2-(3-phenylphenyl)-4-methylpentanoic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.119 g, 49%). MS (ESI): 520.3 (M&plus;H) &plus; . 
 Example 25 
 Preparation of N-&lsqb;4-methyl-2-(3-phenyl)phenylpentanoyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 2(a)-2(c), except substituting aniline for isobutylamine and isobutyryl chloride for cyclopropane carbonyl chloride in step (a), and 2-(3-phenylphenyl)-4-methylpentanoic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (c), the title compound was prepared as a white solid (72 mg, 52%). MS (ESI): 541.3 (M&plus;H) &plus; . 
 Example 26 
 Preparation of N-&lsqb;2-(2-methoxy-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 3(a)-3(g), except substituting 1-bromo-2-methoxynaphthalene for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as a white solid (0.194 g, 85%). MS (ESI): 548.3 (M&plus;H) &plus; . 
 Example 27 Preparation of N-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;4-methyl-2-(3-phenyl)phenylpentanoyl&rsqb;hydrazide 
 a) 2-benzyloxybromobenzene To a stirring solution of 2-bromophenol (10.0 g, 57.8 mmol), and benzyl bromide (9.9 g, 57.8 mmol) in acetone (150 mL) was added K 2 CO 3 (12.0 g, 86.7 mmol). After stirring at reflux for 4 h, the mixture was partitioned between ethyl acetate and water. The organic layer was washed with brine, dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a colorless oil (15.2 g, 57.8 mmol). 1 HNMR (400 MHz, CDCl 3 ) d 7.62 (m, 1H), 7.54 (m, 2H), 7.45 (m, 2H), 7.37 (m, 1H), 7.28 (m, 1H), 6.98 (m, 1H), 6.01 (m, 1H), 5.17 (s, 2H). 
 b) 2-benzyloxyphenylboronic Acid To a stirring solution of the compound of Example 27(a) (15.2 g, 57.8 mmol) in THF (100 mL) at −78° C. was added dropwise n-BuLi (23.1 mL, 2.5M in hexane, 57.8 mmol). The mixture stirred at −78° C. for 25 min when added via cannulation to a stirring solution of triisopropylborate (54.4 g, 289 mmol) in THF (100 mL) at −78° C. After warming to room temperature and stirring for 3 h, the mixture was poured into 3N HCl (100 mL) and extracted with ethyl acetate (3×200 mL). The organic layers were combined, washed successively with water and brine, dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a pale yellow solid (6.9 g, 30.3 mmol). 1 HNMR (400 MHz, CDCl 3 ) d 7.90 (d, 1H), 7.42 (m, 6H), 7.07 (t, 1H), 7.02 (d, 1H), 6.05 (s, 2H), 5.16 (s, 2H). 
 c) N-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;4-methyl-2-(3-phenyl)phenylpentanoyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 2-benzyloxyphenylboronic acid acid for 4-methyl-1-naphthalene boronic acid in step (e) and 2-(3-phenylphenyl)-4-methylpentanoic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.194 g, 85%). MS (ESI): 576.3 (M&plus;H) &plus; . 
 Example 28 
 Preparation of N-&lsqb;2-(2-benzyloxy-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) 1-bromo-2-methoxymethoxynaphthalene To a stirred suspension of sodium hydride (1.6 g, 40.3 mmol, 60% dispersion in mineral oil) in DMF (150 mL) at 0° C. was added 1-bromo-2-naphthol (5.0 g, 22.4 mmol) dropwise. After stirring for 20 min, bromomethyl methyl ether (2.8 g, 22.4 mmol) was added slowly. After warning to room temperature and stirring for 4 h, the mixture was poured into water and extracted with ethyl acetate. The organic phase was washed with saturated aqueous NaHCO 3 and brine then dried (MgSO 4 ), filtered and concentrated to a red oil (5.98 g, 100%). 1 H NMR (400 MHz, CDCl 3 ) d 8.27 (d, 1H), 7.79 (d, 2H), 7.60(t, 1H), 7.46 (m, 2H), 5.38 (s, 2H), 3.61 (s, 3H). 
 b) ethyl 2-(2-methoxymethoxy-1-naphthyl)thiazole-4carboxylate Following the procedure of Example 3(a)-3(e), except substituting 1-bromo-2-methoxymethoxynaphthalene for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as an off-white solid (0.136 g, 15%). MS (ESI): 344.2 (M&plus;H) &plus; . 
 c) ethyl 2-(2-hydroxy-1-naphthyl)thiazole-4-carboxylate To a stirring solution of the compound of Example 28(b) (0.136 g, 0.397 mmol) in EtOH (3 mL) was added concentrated hydrochloric acid (5 drops). After stirring at reflux for 3 h, the solution was concentrated, redissolved in ethyl acetate, and washed successively with saturated aqueous NaHCO 3 and brine. The organic layer was dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a white solid (0.080 g, 67%). MS (ESI): 300.2 (M&plus;H) &plus; . 
 d) ethyl 2-(2-benzyloxy-1-naphthyl)thiazole-4-carboxylate To a stirring solution of the compound of Example 28(c) (0.080 g, 0.268 mmol), benzyl alcohol (0.038 g, 0.348 mmol) and triphenylphosphine (0.091 g, 0.348 mmol) in THF (3 mL) at 0° C. was added diisopropyl azodicarboxylate (0.070 g, 0.348 mmol) dropwise. After stirring at room temperature for 16 h, the solution was concentrated and the residue purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a white solid (0.060 g, 58%). 1 H NMR (400 MHz, CDCl 3 ) d 8.41 (s, 1H), 8.12 (d, 1H), 7.91 (d, 1H), 7.80 (d, 1H), 7.52 (t, 1H), 7.41 (t, 1H), 7.34 (m, 6H), 5.24 (s, 2H), 4.49 (q, 2H), 1.44 (t, 3H). 
 e) N-&lsqb;2-(2-benzyloxy-1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(d)-1(h), except substituting ethyl 2-(2-benzyloxy-1-naphthyl)thiazole-4-carboxylate for ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate (d), the title compound was prepared as a white solid (0.050 g, 52%). MS (ESI): 624.2 (M&plus;H) &plus; . 
 Example 29 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 4(a)-4(d), except substituting 2-pyridylcarbinol for 4-pyridylcarbinol in step (a) and diisobutylamine for N-methyl isobutylamine in step (d), the title compound was prepared as a yellow solid (40 mg, 20%). MS (ESI): 533.4 (M&plus;H) &plus; . 
 Example 30 
 Preparation of N-&lsqb;2-(9-phenanthrenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 3(a)-3(g), except substituting 9-bromophenanthrene for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as an off-white solid (0.085 g, 48%). MS (ESI): 568.2 (M&plus;H) &plus; . 
 Example 31 
 Preparation of N-&lsqb;2-(9-anthracenyl)thiazol-4ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 3(a)-3(g), except substituting 9-bromoanthracene for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as a white solid (0.101 g, 67%). MS (ESI): 568.2 (M&plus;H) &plus; . 
 Example 32 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N-(-tert-butoxycarbonyl-L-leucinyl)ydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting diisobutylamine for cis-2,-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a yellow solid (950 mg, 78% yield). MS (ESI): 484.3 (M&plus;H) &plus; . 
 Example 33 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(L-leucinyl)&rsqb;hydrazide Following the procedure of 4(c), except substituting N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(-tert-butoxycarbonyl-L-leucinyl)ydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a yellow solid (370 mg, 85%). MS (ESI): 384.3 (M&plus;H) &plus; . 
 Example 34 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-methyl-N-(3-pyridinylmethoxycarbonyl)-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.100 g, 59%). MS (ESI): 532.2 (M&plus;H) &plus; . 
 Example 35 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-leucinyl)hydrazide Following the procedure of Example 1(h), except substituting N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(L-leucinyl)&rsqb;hydrazide for N-&lsqb;2-(cis-2,-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and picolinic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the title compound was prepared as a yellow solid (40 mg, 30%). MS (ESI): 489.3 (M&plus;H) &plus; . 
 Example 36 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylproplylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyrazinecarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1 (h), except substituting N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(L-leucinyl)&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and pyrazinecarboxylic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the title compound was prepared as a yellow solid (45 mg, 35%). MS (ESI): 490.3 (M&plus;H) &plus; . 
 Example 37 
 Preparation of N-&lsqb;N,N-bis-(2-methylpropyl)carbamoyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) Nisobutylaniline Following the procedure of Example 2(a)-2(d), except substituting aniline for isobutylamine and isobutyryl chloride for cyclopropane carbonyl chloride in step (a), the title compound was prepared as an orange liquid (2.11 g, 83% yield). MS (ESI): 172.2 (M&plus;Na) &plus; . 
 b) N-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d), except substituting N-isobutylaniline for cis-2,6-dimethylmorpholine in step (a), the title compound was prepared as a white solid. MS (ESI): 291.3 (M&plus;H) &plus; . 
 c) N-&lsqb;N,N-bis-(2-methylpropyl)carbamoyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 23(c), except substituting N-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for 2-(1-naphthyl)thiazol-4-ylcarbonylhydrazide and diisobutylamine for N-(3-phenyl)phenyl isobutylamine, the title compound was prepared as a white solid (25 mg, 25%). MS (ESI): 446.3 (M&plus;H) &plus; . 
 Example 38 
 Preparation of N-(2-phenylthiazol-4-ylcarbonyl)-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting phenylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e), the title compound was prepared as a white solid (0.077 g, 27%). MS (ESI): 468.2 (M&plus;H) &plus; . 
 Example 39 
 Preparation of N-&lsqb;2-&lsqb;2-(4-tert-butoxycarbonyl)benzyloxyphenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) tert-butyl 4-bromomethylbenzoate To a stirring solution of 4-bromomethylbenzoic acid (4.0 g, 18.6 mmol) in cyclohexane (37 mL), dichloromethane (19 mL) and THF (2 mL) was added a solution of tert-butyl-2,2,2-trichloroacetimidate (8.1 g, 37.2 mmol) in cyclohexane (12 mL) followed by a catalytic amount of boron trifluoride etherate. After stirring at room temperature for 18 h, NaHCO 3 (4 g) was added and the mixture filtered. The mixture was filtered through a short plug of silica gel and concentrated to yield the title compound as a colorless oil that solidifies on standing (3.6 g, 71%). 1 H NMR (400 MHz, CDCl 3 ) d 7.98 (d, 2H), 7.44 (d, 2H), 4.50 (s, 2H), 1.59 (s, 9H). 
 b) ethyl 2-(2-hydroxyphenyl)thiazole-4-carboxylate Following the procedure of Example 28(a)-28(c), except substituting 2-bromophenol for 1-bromo-2-naphthol in step (a), the title compound was prepared as a white solid (0.560 g, 53%). MS (ESI): 250.1 (M&plus;H) &plus; . 
 c) ethyl 2-&lsqb;2-(4-tert-butoxycarbonylbenzyloxy)phenyl&rsqb;thiazole-4-carboxylate To a stirring mixture of the compound of Example 39(b) (0.094 g, 0.379 mmol) and potassium carbonate (0.136 g, 0.985 mmol) in acetone (10 mL) was added the compound of Example 39(a) (0.133 g, 0.417 mmol). After stirring at reflux for 16 h, the mixture was partitioned between ethyl acetate and water. The organic layer was washed with brine, dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a white solid (0.160 g, 96%). MS (ESI): 440.2 (M&plus;H) &plus; . 
 d) N-&lsqb;2-&lsqb;2-(4-tert-butoxycarbonyl)benzyloxyphenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(d)-1(h), except substituting ethyl 2-&lsqb;2-(4-tert-butoxycarbonylbenzyloxy)phenyl&rsqb;thiazole-4-carboxylate for ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate in step (d), the title compound was prepared as a white solid (0.124 g, 47%). MS (ESI): 674.2 (M&plus;H) &plus; . 
 Example 40 
 Preparation of N-&lsqb;2-&lsqb;2-(4-carboxybenzyloxy)phenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of 4(c), except substituting N-&lsqb;2-&lsqb;2-(4-tert-butoxycarbonyl)benzyloxyphenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a pale yellow solid (0.130 g, 100%). MS (ESI): 618.2 (M&plus;H) &plus; . 
 Example 41 
 Preparation of N-&lsqb;N-(4-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N-isobutylaniline Following the procedure of Example 2(a)-2(b), except substituting aniline for isobutylamine and isobutyryl chloride for cyclopropane carbonyl chloride in step (a), the title compound was prepared as an orange liquid (2.11 g, 83%). MS (ESI): 335.3 (M&plus;Na) &plus; . 
 b) (4-tert-butoxycarbonyl)benzyl Alcohol Water (5 mL) and potassium carbonate (710 mg, 5.15 mmol) were added to a solution of the compound of Example 39(a) (280 mg, 1.03 mmol) in dioxane (5 mL). The mixture was heated at reflux overnight, then the dioxane was removed under reduced pressure. Methylene chloride was added followed by treatment with dilute HCl until all solid had dissolved. The organic phase was separated, washed with aqueous sodium bicarbonate, dried (MgSO 4 ), filtered and concentrated to afford the title compound as a white solid (214 mg, 100%). 1 H NMR (400 MHz, CDCl 3 ) d 7.89 (d, 2H), 7.33 (d, 2H), 4.67 (s, 2H), 3.08 (s, 1H), 1.57 (s, 9H). 
 c) N-&lsqb;N-(4-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-isobutylaniline for cis-2,6-dimethylmorpholine in step (a) and (4-tertbutoxycarbonyl)benzyl alcohol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (15 mg, 17%). MS (ESI): 638.2 (M&plus;H) &plus; . 
 Example 42 
 Preparation of N-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting diisobutylamine for cis-2,6-dimethylmorpholine in step (a) and (4-tertbutoxycarbonyl)benzyl alcohol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (35 mg, 16%). MS (ESI): 618.4 (M&plus;H) &plus; . 
 Example 43 
 Preparation of N-&lsqb;N-(4-carboxybenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of 4(c), except substituting N-&lsqb;N-(4-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-&lsqb;N-(2-methylpropyl)-N-phenylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a yellow solid (10 mg, 85%). MS (ESI): 582.2 (M&plus;H) &plus; . 
 Example 44 
 Preparation of N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;2-(4-tert-butoxycarbonyl)benzyloxyphenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(d) and 1(h), except substituting ethyl 2-&lsqb;2-(4-tert-butoxycarbonylbenzyloxy)phenyl&rsqb;thiazole-4-carboxylate for ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate in step (d) and N-benzyloxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (0.102 g, 68%). MS (ESI): 673.2 (M&plus;H) &plus; . 
 Example 45 
 Preparation of N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;2-(4-carboxybenzyloxy)phenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of 4(c), except substituting N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;2-(4-tert-butoxycarbonyl)benzyloxyphenyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a pale yellow solid (0.103 mg, 100%). MS (ESI): 632.2 (M&plus;H) &plus; . 
 Example 46 
 Preparation of N-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 6-methyl-3-pyridylcarbinol Following the procedure of Example 2(b), except substituting methyl 6-methylnicotinate for N-cyclopropylmethyl isobutyramide, the title compound was prepared as a yellow oil (4.32 g, 83%). MS (ESI): 123.8 (M&plus;H) &plus; . 
 b) N-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 5(a)-5(b), except substituting 6-methyl-3-idylcarbinol for 3-pyridylcarbinol in step (a), the title compound was prepared as a white solid (0.155 g, 63%). MS (ESI): 532.2 (M&plus;H) &plus; . 
 Example 47 
 Preparation of N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and N-benzyloxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (156 mg, 75%). MS (ESI): 500.3 (M&plus;H) &plus; . 
 Example 48 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and 2-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (260 mg, 73%). MS (ESI): 501.1 (M&plus;H) &plus; . 
 Example 49 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and 6-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (151 mg, 71%). MS (ESI): 515.3 (M&plus;H) &plus; . 
 Example 50 
 Preparation of N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (1.2 g, 72%). MS (ESI): 466.3 (M&plus;H) &plus; . 
 Example 51 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′&lsqb;-N-methyl-N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 4(a)-4(d), except substituting 2-pyridylcarbinol for 4-pyridylcarbinol in step (a) and cyclopropylmethyl cyclopropylamine for N-methyl isobutylamine in step (d), the title compound was prepared as a white solid (60 mg, 25%). MS (ESI): 515.3 (M&plus;H) &plus; . 
 Example 52 
 Preparation of N-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucine Following the procedure of Example 1(f)-1(g), except substituting 6-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as an off-white solid (5.8 g, 100%). 1 H NMR (400 MHz, CDCl 3 ) d 8.36 (s, 1H), 7.61 (d, 1H), 7.15 (d, 1H), 5.85 (d, 1H), 5.01 (s, 2H), 4.20 (m, 1H), 2.50 (s, 3H), 1.62 (m, 2H), 1.49 (m, 1H), 0.87 (t, 6H). 
 b) N-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 2-benzyloxyphenylboronic acid acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-(6-methyl-3-pyridinylmethoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (178 mg, 99%). MS (ESI): 588.3 (M&plus;H) &plus; . 
 Example 53 
 Preparation of N-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) 2-methyl-3-pyridylcarbinol Following the procedure of Example 2(b), except substituting methyl 2-methylnicotinate for N-cyclopropylmethyl isobutyramide, the title compound was prepared as a pale yellow oil (4.89 g, 100%). MS (ESI): 123.8 (M&plus;H) &plus; . 
 b) N-3-(6-methyl)pyridylmethoxycarbonyl-(L)-leucine Following the procedure of Example 1(f)-1(g), except substituting 2-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (6.73 g, 100%). MS (ESI): 281.3 (M&plus;H) &plus; . c) N-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 2-benzyloxyphenylboronic acid acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-(2-methyl-3-pyridinylmethoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a pale yellow solid (179.1 mg, 99%). MS (ESI): 588.3 (M&plus;H) &plus; . 
 Example 54 
 Preparation of N-&lsqb;2-&lsqb;N-methyl-N-(2-methylpropylamino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-methyl isobutylamine for cis-2,6-dimethylmorpholine in step (a) and 6-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a pale yellow solid (215 mg, 100%). MS (ESI): 491.3 (M&plus;H) &plus; . 
 Example 55 
 Preparation of N-&lsqb;2-&lsqb;N-methyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-methyl isobutylamine for cis-2,6-dimethylmorpholine in step (a) and 2-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a pale yellow solid (215 mg, 100%). MS (ESI): 491.3 (M&plus;H) &plus; . 
 Example 56 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′(N-picolinoyl-L-leucinyl)hydrazide 
 a) N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)&rsqb;thiazol-4-yl-carbonyl&rsqb;-N′-(L-leucinyl)hydrazide Following the procedure of 4(c), except substituting N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a white solid (668 mg, 81%). MS (ESI): 366.3 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-leucinyl)hydrazide Following the procedure of Example 1(h), except substituting N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)&rsqb;thiazol-4-yl-carbonyl&rsqb;-N′-(L-leucinyl)hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and picolinic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (183 mg, 95%). MS (ESI): 471.2 (M&plus;H) &plus; . 
 Example 57 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and 2-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (310 mg, 84%). MS (ESI): 515.4 (M&plus;H) &plus; . 
 Example 58 
 Preparation of N-&lsqb;N-(3-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 3-bromomethylbenzoic Acid A mixture of 3-toluic acid (15.0 g, 110 mmol), N-bromosuccinimide (19.60 g, 110 mmol) and t-butyl peroxybenzoate (2.1 mL, 110 mmol) in carbon tetrachloride (50 mL) was heated at reflux overnight. The mixture was cooled and concentrated under reduced pressure. The residue obtained was washed with carbon tetrachloride and filtered under vacuum. The filtrate was evaporated to dryness to yield a white solid (12.57 g, 53%). 1 H NMR (400 MHz, CDCl 3 ) d 7.93 (m, 2H), 7.43 (m, 2H), 4.55 (s, 2H). 
 b) tert-butyl 3-bromomethylbenzoate Followiong the procedure of Exmaple 39(a), except substituting 3-bromomethylbenzoic acid for 4-bromomethylbenzoic acid, the title compound was prepared as a yellow oil (7.9 g, 100%). 1 H NMR (400 MHz, CDCl 3 ) d 7.93 (m, 2H), 7.43 (m, 2H), 4.55 (s, 2H), 1.55 (s, 9H). 
 c) (3-tert-butoxycarbonyl)benzyl alcohol Followiong the procedure of Example 41(b), except substituting tert-butyl 3-bromomethylbenzoate for tert-butyl 4-bromomethylbenzoate, the title compound was prepared as a yellow oil (5.6 g, 92%). MS (ESI): 208.1 (M&plus;H) &plus; . 
 d) N-&lsqb;N-(3-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and (3-tertbutoxycarbonyl)benzyl alcohol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (90 mg, 29%). MS (ESI): 600.4 (M&plus;H) &plus; . 
 Example 59 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;hydrazide 
 a) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 3(a)-3(f), except substituting 1-naphthalene boronic acid for 4-methyl-1-naphthalene boronic acid in step (e), the title compound was prepared as a pale yellow solid. MS (ESI): 270.1 (M&plus;H) &plus; . 
 b) N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide in and N-tert-butoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step, the title compound was prepared as a white solid (2.2 g, 96%). MS (ESI): 483.2 (M&plus;H) &plus; . 
 c) N-(L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of 4(c), except substituting N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as an off-white solid (1.7 g, 97%). MS (ESI): 383.3 (M&plus;H) &plus; . 
 d) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-(L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and 8-quinolinecarboxylic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (118 mg, 84%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 60 
 Preparation of N-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 5(a)-5(b), except substituting 2-methyl-3-idylcarbinol for 3-pyridylcarbinol in step (a), the title compound was prepared as a white solid (0.160 g, 65%). MS (ESI): 532.2 (M&plus;H) &plus; . 
 Example 61 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-leucinyl)hydrazide Following the procedure of Example 59(a)-59(c), except substituting picolinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.086 g, 54%). MS (ESI): 488.3 (M&plus;H) &plus; . 
 Example 62 
 Preparation of N-&lsqb;N-(3-carboxybenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of 4(c), except substituting N-&lsqb;N-(3-tert-butoxycarbonylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a white solid (21 mg, 93%). MS (ESI): 544.3 (M&plus;H) &plus; . 
 Example 63 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 2-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.123 g, 80%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 64 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 3-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.109 g, 77%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 65 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylpiperidinecarbonyl-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 1-methylpiperidine-4-carboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.059 g, 45%). MS (ESI): 508.2 (M&plus;H) &plus; . 
 Example 66 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 4-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.096 g, 68%). MS (ESI): 538.3 (M&plus;H) &plus; . 
 Example 67 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(5-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 5-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.089 g, 63%). MS (ESI): 538.3 (M&plus;H) &plus; . 
 Example 68 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(7-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 7-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.106 g, 75%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 69 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 6-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.111 g, 79%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 70 
 Preparation of N-&lsqb;N-(1-isoquinolinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 1-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.076 g, 54%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 71 
 Preparation of N-&lsqb;N-(3-isoquinolinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 3-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.055 g, 39%). MS (ESI): 538.2 (M&plus;H) &plus; . 
 Example 72 
 Preparation of N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 4-methylimidazole-5-carboxylic Acid Following the procedure of Example 1(g), except substituting ethyl 4-methylimidazole-5-carboxylate for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid (0.428 g, 52%). MS (ESI): 126.8 (M&plus;H) &plus; . 
 b) N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-(L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and 4-methylimidazole-5-carboxylic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (0.108 g, 84%). MS (ESI): 491.3 (M&plus;H) &plus; . 
 Example 73 
 Preparation of N-(N-benzyl-L-prolinyl-L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-benzyl proline for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.075 g, 50%). MS (ESI): 570.2 (M&plus;H) &plus; . 
 Example 74 
 Preparation of N-&lsqb;N-(1-benzyl-5-methylimidazol-4-ylcarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 72(a)-72(b), except substituting 1-benzyl-5-methylimidazole-4-carboxylic acid for 4-methylimidazole-5-carboxylic acid in step (a), the title compound was prepared as a white solid (0.115 g, 75%). MS (ESI): 581.1 (M&plus;H) &plus; . 
 Example 75 
 Preparation of N-&lsqb;N-(3-methylisonicotinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 4-cyano-2-methylpyridine To neat picoline N-oxide (10.0 g, 91.7 mmol) at room temperature was added iodoethane (51.5 g, 330 mmol) dropwise. After standing for 24 h, the salt was filtered off and washed with ether. The solid was dissolved in ethanol/water (70 mL/30 mL) and potassium cyanide (11.0 g, 172 mmol) in water (31 mL) was added dropwise over 100 min at 48-50° C. After the addition was complete, the solution continued stirring at the same temperature for 30 min. The solution was then extracted with chloroform. The organic layer was washed with brine, dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a pale yellow oily solid (3.9 g, 36%). MS (ESI): 118.8 (M&plus;H) &plus; . 
 b) 2-methylpyridine-4-carboxylic Acid The compound of Example 75(a) (0.300 g, 2.5 mmol) was dissolved in concentrated hydrochloric acid (3 mL). After stirring at reflux for 18 h, the solution was concentrated to yield the title compound as a white solid (0.342 g, 100%). MS (ESI): 137.8 (M&plus;H) &plus; . 
 c) N-&lsqb;N-(3-methylisonicotinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-(L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and 2-methylpyridine-4-carboxylic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine, the tide compound was prepared as a white solid (0.095 g, 72%). MS (ESI): 502.2 (M&plus;H) &plus; . 
 Example 76 
 Preparation of N-&lsqb;2-cyclopropylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and 2-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (140 mg, 50%). MS (ESI): 447.3 (M&plus;H) &plus; . 
 Example 77 
 Preparation of N-&lsqb;N-(2-benzoxazolyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide A solution of the compound of Example 59(c) (100 mg, 0.26 mmol), 2-chlorobenzoxazole (40.2 mg, 0.26 mmol, 0.03 mL) and triethylamine (26.5 mg, 0.26 mmol, 0.365 mL) in 1:1 THF/methanol (1 mL) was heated at 60° C. for 48 h. The solution was diluted with ethyl acetate, washed with saturated aqueous NaHCO 3 , water (2×) and saturated brine, then dried (MgSO 4 ), filtered and concentrated. The residue was purified by flash chromatography on 4 g of 230-400 mesh silica gel, eluting with 1:1 ethyl acetate/hexanes, to give the title compound as a pale yellow solid (50.2 mg, 38%). MS (ESI): 500.2 (M&plus;H) &plus; . 
 Example 78 
 Preparation of N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;oxazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N,N-diisobutylurea A solution of diisobutylamine (4.5 g, 34.8 mmol, 6.08 mL) and chlorosulfonyl isocyanate (4.93 g, 34.8 mmol, 3.03 mL) in THF (200 mL) was allowed to stir at room temperature for 20 min, then water (10 mL) was added and the solution was allowed to stir at room temperature for 17 h. The solution was concentrated, the residue was redissolved in ethyl acetate, washed with water, saturated aqueous NaHCo 3 and saturated brine, then dried (MgSO 4 ), filtered and concentrated to give the title compound as a colorless oil which crystallized upon standing (6.0 g, 100%). MS (ESI): 173.3 (M&plus;H) &plus; . 
 b) N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N,N-bis-(2-methylpropyl)amino&rsqb;oxazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 1(c)-1(d) and 1(h), except substituting N,N-diisobutylurea for cis-2,6-dimethyl-4-morpholinothiourea in step (c) and N-benzyloxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (126 mg, 64%). MS (ESI): 502.3 (M&plus;H) &plus; . 
 Example 79 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-cyclopropyl Isobutylamine Following the procedure of Example 9(a), except substituting isobutyraldehyde for cyclopropane carboxaldehyde, the title compound was prepared as a colorless oil (1.9 g, 58%). MS (ESI): 113.9 (M&plus;H) &plus; . 
 b) N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropyl isobutylamine for cis-2,6-dimethylmorpholine in step (a) and 2-pyridyocarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (150 mg, 69% yield). MS (ESI): 503.2 (M&plus;H) &plus; . 
 Example 80 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-methyl-N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 4(a)-4(d), except substituting 2-pyridylcarbinol for 4-pyridylcarbinol in step (a) and N-cyclopropyl isobutylamine for N-methyl isobutylamine in step (d), the title compound was prepared as a white solid (85 mg, 32%). MS (ESI): 517.3 (M&plus;H) &plus; . 
 Example 81 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(1-piperazinecarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-tert-butoxycarbonyl-1-piperazinecarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 23(c), except substituting N-tert-butoxycarbonylpiperazine for N-(3-phenyl)phenyl isobutylamine, the title compound was prepared as a white solid (131 mg, 85%). MS (ESI): 595.2 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(1-piperazinecarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of 4(c), except substituting N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-tert-butoxycarbonyl-1-piperazinecarbonyl)-L-leucinyl&rsqb;hydrazide for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a white solid (47 mg, 54%). MS (ESI): 495.2 (M&plus;H) &plus; . 
 Example 82 
 Preparation of N-&lsqb;4-methyl-2-(4-phenoxy)phenylpentanoyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 17(a)-17(c), except substituting 4-phenoxyphenylacetic acid for 4-phenoxyphenylacetic acid in step (a), the title compound was prepared as a white solid (134 mg, 67%). MS (ESI): 536.2 (M&plus;H) &plus; . 
 Example 83 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide 
 a) bis-(cyclopropylmethyl)amine Following the procedure of Example 9(a), except substituting aminomethylcyclporopane for cyclopropylamine, the title compound was prepared as a colorless liquid (2.5 g, 96%). MS (ESI): 125.8 (M&plus;H) &plus; . 
 b) N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except bis-(cyclopropylmethyl)amine for cis-2,6-dimethylmorpholine in step (a) and 2-pyridyocarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a yellow solid (115 mg, 30%). MS (ESI): 515.3 (M&plus;H) &plus; . 
 Example 84 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 2-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (125 mg, 59%). MS (ESI): 521.2 (M&plus;H) &plus; . 
 Example 85 
 Preparation of N-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(8-quinolinyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N-&lsqb;2-(8-quinolinyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 3(a)-3(f), except substituting 8-bromoquinoline for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as a pale yellow solid (0.306 g, 100%). MS (ESI): 271.2 (M&plus;H) &plus; . 
 b) N-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(8-quinolinyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(b)-59(d), except substituting N-&lsqb;2-(8-quinolinyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide in step (b), the title compound was prepared as a white solid (0.111 g, 66%). MS (ESI): 539.2 (M&plus;H) &plus; . 
 Example 86 
 Preparation of N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-benzyloxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.145 g, 60%) MS(ESI): 517.3 (M&plus;H) &plus; . 
 Example 87 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 3-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (150 mg, 75%). MS (ESI): 521.2 (M&plus;H) &plus; . 
 Example 88 
 Preparation of N-&lsqb;2-N-cyclppropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-isoquinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 3-isoquinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (187 mg, 82%). MS (ESI): 521.1 (M&plus;H) &plus; . 
 Example 89 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 6-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (155 mg, 59%). MS (ESI): 521.3 (M&plus;H) &plus; . 
 Example 90 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 83(a)-83(b), except substituting 2-methyl-3-pyridylcarbinol for 2-pyridylcarbinol in step (b), the title compound was prepared as a yellow solid (105 mg, 46%). MS (ESI): 529.3 (M&plus;H) &plus; . 
 Example 91 
 Preparation of N-(N-benzyloxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N-benzyloxycarbonyl-L-b-tert-butylalanine To a stirring solution of L-b-tert-butylalanine (1.0 g, 6.89 mmol) in water (2.1 mL) and 5 N NaOH (1.38 mL) at 0° C. was added benzyl chloroformate (1.3 g, 7.58 mmol) and 2 N NaOH (3.8 mL) in ten alternating portions, over 1.5 h. After the additions are complete the mixture was stirred for another 30 min. at room temperature. The pH is then taken to 10 and the mixture is extracted with ether (50 mL). The aqueous layer was acidified to pH 3 with 3 N HCl and extracted with ether (3×50 mL). The organic layers are combined, dried (MgSO 4 ), filtered and concentrated to yield the title compound as a colorless oil (1.59 g, 83%). MS(ESI): 278.2 (M&plus;H) − . 
 b) N-(N-benzyloxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-benzyloxycarbonyl-L-tert-butylalanine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.214 g, 87%). MS (ESI): 531.3 (M&plus;H) &plus; . 
 Example 92 
 Preparation of N-(N-benzyloxycarbonyl-L-cyclopropylalanyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N-benzyloxycarbonyl-L-allylglycine Following the procedure of Example 91(a), except substituting L-allylglycine for L-tert-butylalanine, the title compound was prepared. 
 b) N-benzyloxycarbonyl-L-cyclopropylalanine Methyl Ester Diazomethane (4.8 mmol in 18 ml Et 2 O) was added to a solution of the compound of Example 92(a) (0.210 g, 0.48 mmol) in 1 ml Et 2 O at room temperature and was stirred for 5 minutes. Then Pd(OAc) 2 (2 mg) was added and the reaction was stirred overnight, filtered through silica gel, concentrated in vacuo, and was used in the next reaction without further purification (205 mg, 95%). MS (ESI): 300.1 (M&plus;Na) &plus; . 
 c) N-benzyloxycarbonyl-L-cyclopropylalanine Following the procedure of Example 1(g) except substituting N-benzyloxycarbonyl-L-cyclopropylalanine methyl ester for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid (165 mg, 82%). MS (ESI): 264.2 (M&plus;H) &plus; . 
 d) N-(N-benzyloxycarbonyl-L-cyclopropylalanyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-benzyloxycarbonyl-(L)-tert-butylalanine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.054 g, 67%). MS (ESI): 515.2 (M&plus;H) &plus; . 
 Example 93 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-&lsqb;3-(2-pyridyl)phenylacetyl&rsqb;-L-leucinyl&rsqb;hydrazide 
 a) methyl 3-9trifluoromethanesulfonyloxyphenylacetate To an oven-dried flask under Argon atmosphere containing sodium hydride (2.54 g, 60% dispersion in mineral oil, 63.5 mmol) was added anhydrous pentane (20 mL). The slurry was stirred for 5 min, allowed to settle, most of the pentane was removed, and anhydrous THF (40 mL) was added. To this suspension was added a solution of methyl 3-hydroxyphenylacetate (9.99 g, 60.1 mmol) in anhydrous THF (20 mL) and the reaction was stirred at room temperature for 20 min. To this mixture was then added a solution of N-phenyltrifluoromethanesulfonimide (22.53 g, 63.1 mmol)) in anhydrous THF (40 mL) and the reaction was stirred at room temperature until TLC analysis indicated the complete consumption of starting material (1.5 h). The reaction was quenched by the addition of H 2 O (10 mL), concentrated to one half original volume, then diluted with CHCl 3 (200 mL) and washed with H 2 O. The aqueous layer was washed with fresh CHCl 3 (50 mL), the combined organic layers were washed with 10% Na 2 CO 3 , H 2 O, and brine, then dried (MgSO 4 ), filtered and concentrated. Column chromatography of the residue (silica gel, 5:95 EtOAc: hexanes, then 10:90 EtOAc: hexanes) gave 17.47 g of the title compound. 1 H NMR (400 MHz, CDCl 3 ) d 7.42 (m, 1H), 7.31-7.19 (m, 3H), 3.72 (s, 3H), 3.68 (s, 2H). 
 b) methyl 3-(2-pyridyl)phenylacetate To a solution of the compound of Example 93(a) (6.86 g, 23.0 mmol) in anhydrous dioxane (100 mL) was added 2-pyridylstannane (8.89 g, 24.1 mmol), LiCl (2.94 g, 69.3 mmol), 2,6-di-tert-butyl-4-methylphenol (a few crystals), and Pd(PPh 3 ) 4 (632.1 mg, 0.55 mmol). The reaction was protected from light with foil and heated to reflux overnight. The reaction was allowed to cool to room temperature and concentrated. Column chromatography of the residue (silica gel, 1:3 EtOAc: hexanes, then 1:2 EtOAc: hexanes) gave 3.85 g of the title compound: MS (ESI): 228.1 (M&plus;H) &plus; . 
 c) 3-(2-pyridyl)phenyl Acetic Acid Following the procedure of Examples 1(g), except substituting methyl 3-(2-pyridyl)phenylacetate for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared. MS (ESI): 214.3 (M&plus;H) &plus; . 
 e) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-&lsqb;3-(2-pyridyl)phenylacetyl&rsqb;-L-leucinyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and 3-(2-pyridyl)phenylacetic acid for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (0.149 g, 79%). MS (ESI): 578.1 (M&plus;H) &plus; . 
 Example 94 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinyl-L-leucinyl)hydrazide 
 a) N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting bis-(cyclopropylmethyl)amine cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as an orange oil. MS (ESI): 480.3 (M&plus;H) &plus; . 
 b) N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinyl-L-leucinyl)hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a), the title compound was prepared as a yellow solid (74 mg, 41%). MS (ESI): 485.3 (M&plus;H) &plus; . 
 Example 95 
 Preparation of N-(N-benzyloxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting bis-(cyclopropylmethyl)amine for cis-2,6-dimethylmorpholine in step (a) and N-bejnzyloxycarbonyl L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as as a yellow solid (140 mg, 69%). MS (ESI): 514.3 (M&plus;H) &plus; . 
 Example 96 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-leucinyl&rsqb;hydrazide 
 a) 6-methylnicotinic Acid Following the procedure of Example 1(g), except substituting methyl-6-methylnicotinate for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid (506 mg, 100%). MS (ESI): 137.9 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylnicotinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 6-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (150 mg, 41%). MS (ESI): 485.4 (M&plus;H) &plus; . 
 Example 97 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methylnicotinoyl)-L-leucinyl&rsqb;hydrazide 
 a) 2-methylnicotinic Acid Following the procedure of Example 1(g), except substituting methyl-2-methylnicotinate for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid (1.6 g, 100%). MS (ESI): 138.2 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-methylnicotinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 2-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (170 mg, 71%). MS (ESI): 485.3 (M&plus;H) &plus; . 
 Example 98 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-methylisonicotinoyl)-L-&rsqb;leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 2-methylpyridine-4-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (120 mg, 57%). MS (ESI): 485.2 (M&plus;H) &plus; . 
 Example 99 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 8-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (200 mg, 94%). MS (ESI): 521.2 (M&plus;H) &plus; . 
 Example 100 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl) hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 8-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a yellow solid (25 mg, 12%). MS (ESI): 535.3 (M&plus;H) &plus; . 
 Example 101 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-isoquinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3-isoquinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a yellow solid (25 mg, 10%). MS (ESI): 535.3 (M&plus;H) &plus; . Example 102 
 Preparation of N-&lsqb;2-&lsqb;4-(2,2-dimethylaminoethoxy)-1-naphthyl&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;hydrazide 
 a) 4-bromo-1-naphthol To a vigorously stirred suspension of 1,4-dibromonaphthalene (15.3 g, 53.7 mmol) in hexane/THF (300 mL) at −78° C. was added n-butyllithium (22.3 mL, 56.4 mmol, 2.5 M in hexane) dropwise. After stirring for an additional 30 min. at −78° C., bis(trimethylsilyl)peroxide (11 g, 61.8 mmol) &lsqb;Taddei, M., Ricci, A., Synthesis, 1986, 633&rsqb; was added slowly via syringe. After warming to room temperature and stirring an additional 3 h, the mixture was diluted with ethyl acetate and washed with 1 N HCl then brine. The organic layer was dried (MgSO 4 ), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as an off-white solid (6.5 g, 54%). MS (ESI): 221.1 (M&plus;H) − . 
 b) 4-bromo-naphthyl tert-butyl Ether Following the procedure of Example 39(a), except substituting 4-bromo-1-naphthol for 4-bromomethylbenzoic acid, the title compound was prepared as a colorless oil (2.34 g, 62%). 1 H NMR (400 MHz, CDCl 3 ) d 8.28 (d, 1H), 8.18 (d, 1H), 7.67 (d, 1H), 7.60 (t, 1H), 7.54 (t, 1H), 7.01 (d, 1H), 1.51 (s, 9H). 
 c) ethyl 2-(4-tert-butoxy-1-naphthyl)thiazole-4-carboxylate Following the procedure of Example 3(a)-3(e), except substituting 4-bromo-1-naphthyl tert-butyl ether for 1-bromo-4-methylnaphthalene in step (d), the title compound was prepared as a white solid (0.783 g, 67%). MS (ESI): 356.2 (M&plus;H) &plus; . 
 d) ethyl 2-(4-hydroxy-1-naphthyl)thiazole-4-carboxylate Following the procedure of 4(c), except substituting ethyl 2-(4-tert-butoxy-1-naphthyl)thiazole-4-carboxylate for N-Methyl-N-(4-pyridinylmethoxycarbonyl)-L-leucine tertbutoxycarbonyl ester, the title compound was prepared as a yellow solid (0.580 g, 88%). MS (ESI): 300.1 (M&plus;H) &plus; . 
 e) ethyl 2-&lsqb;4-(2-N,N-dimethylaminoethoxy)-1-naphthyl&rsqb;thiazol-4-carboxylate Following the procedure of Example 28(d), except substituting ethyl 2-(4-hydroxy-1-naphthyl)thiazole-4-carboxylate for ethyl 2-(2-hydroxy-1-naphthyl)thiazole-4-carboxylate and 2-(N,N-dimethylamino)ethanol for benzyl alcohol, the title compound was prepared as a white solid (0.097 g, 52%). MS (ESI): 371.3 (M&plus;H) &plus; . 
 f) N-(8-quinolinoyl)-L-leucine Methyl Ester Following the procedure of Example 1(h), except substituting L-leucine methyl ester hydrochloride for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and 8-quinoline carboxylic acid for N-(4-pyridylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (0.637 g, 41%). MS (ESI): 301.2 (M&plus;H) &plus; . 
 g) N-(8-quinolinoyl)-L-leucine Following the procedure of Example 1(g), except substituting N-(8-quinolinoyl)-L-leucine methyl ester for N-(4-pyridylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid (0.150 g, 25%). 1 H NMR (400 MHz, CDCl 3 ) d 8.89 (t, 1H), 8.78 (d, 1H), 8.21 (d, 1H), 7.90 (d, 1H), 7.57 (t, 1H), 7.43 (t, 1H),4.88 (m, 1H), 1.92 (m, 3H), 1.03 (m, 6H). 
 h) N-&lsqb;2-&lsqb;4-(2,2-dimethylaminoethoxy)-1-naphthyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(d), except substituting ethyl 2-&lsqb;4-(2-N,N-dimethylaminoethoxy)-1-naphthyl&rsqb;thiazole-4-carboxylate for ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate, the title compound was prepared as a yellow solid (0.091 g, 100%). MS (ESI): 357.2 (M&plus;H) &plus; . 
 i) N-&lsqb;2-&lsqb;4-(2,2-dimethylaminoethoxy)-1-naphthyl&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-&lsqb;2-&lsqb;4-(2,2-dimethylaminoethoxy)-1-naphthyl&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and N-(8-quinolinoyl)-L-leucine for N-(4-pyridylmethoxycarbonyl)-L-leucine, the title compound was prepared as a yellow solid (0.050 g, 31%). MS (ESI): 625.2 (M&plus;H) &plus; . 
 Example 103 
 Preparation of N-&lsqb;2-(N-cyclopropyl 1-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(7-quinolinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 7-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (100 mg, 50%). MS (ESI): 521.2 (M&plus;H) &plus; . 
 Example 104 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a yellow solid (40 mg, 15%). MS (ESI): 499.3 (M&plus;H) &plus; . 
 Example 105 
 Preparation of N-&lsqb;2-&lsqb;N-bis-(cyclopropylmethyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-(N-methyl-L-prolinyl-L-leucinyl)hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-methyl-L-proline for picolinic acid in step (b), the title compound was prepared as a white solid (62 mg, 48%). MS (ESI): 477.3 (M&plus;H) &plus; . 
 Example 106 
 Preparation of N-(N-benzyloxycarbonyl-L-norvalinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-benzyloxycarbonyl-L-norvaline for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (180 mg, 96%). MS (ESI): 503.2 (M&plus;H) &plus; . 
 Example 107 
 Preparation of N-(N-benzyloxycarbonyl-L-isoleucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-benzyloxycarbonyl-L-isoleucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (167 mg, 87%). MS (ESI): 517.1 (M&plus;H) &plus; . 
 Example 108 
 Preparation of N-&lsqb;N-(4-dimethylaminomethylbenzoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) methyl 4(N,N-dimethylaminomethyl)benzoate Methyl 4-(bromomethyl)benzoate (2.0 g, 8.73 mmol) was added to a saturated solution of dimethylamine in methanol. After stirring for 25 min, the solution was concentrated and the residue was partitioned between 1N NaOH and ethyl acetate. The organic layer was washed with saturated brine, dired (MgSO 4 ), filtered, and concentrated to provide the title compound as a colorless liquid (1.67 g, 99%). 1 H NMR (250 MHz, CDCl 3 ) d 8.00 (d, 2H), 7.39 (d, 2H), 3.91 (s, 3H), 3.47 (d, 2H), 2.25 (s, 6H). 
 b) 4-(N,N-dimethylaminomethyl)benzoic Acid Following the procedure of Example 1(g), except substituting methyl 4-(N,N-dimethylaminomethyl)benzoate for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid (1.6 g, 100%). 1 H NMR (400 MHz, CD 3 OD) d 7.94 (d, 2H), 7.36 (d, 2H), 3.64 (s, 2H), 2.35 (s, 6H). 
 c) N-&lsqb;N-(4-dimethylaminomethylbenzoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 4-(N,N-dimethylaminomethyl)benzoic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (87 mg, 61%). MS (ESI): 544.2 (M&plus;H) &plus; . 
 Example 109 
 Preparation of N-(N-benzyloxycarbonyl-L-norleucinyl)-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Examples 3(a)-3(c) and 3(e)-3(g), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthalene boronic acid in step (e) and N-benzyloxycarbonyl-L-norleucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (g), the title compound was prepared as a white solid (184 mg, 96%). MS (ESI): 517.1 (M&plus;H) &plus; . 
 Example 110 
 Preparation of N-&lsqb;N-(4-dimethylaminomethylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) 4-(N,N-dimethylamino)benzyl Alcohol To a stirring solution of the compound of Example 108(a) (1.63 g, 8.4 mmol ) in 25 mL of ether, cooled to 0° C., was added dropwise a 1 M solution of lithium aluminum hydride (8.4 mmol, 8.4 mL). After 5 min, the reaction was quenched by the addition of water (0.33 mL), 15% aqueous NaOH (0.33 mL) and water (1.0 mL). The precipitate was removed by filtration, washed with ether 2 times and the filtrate was concentrated to provide the title compound as a colorless oil (1.36 g, 98%). 1 H NMR (250 MHz, CDCl 3 ) d 7.32 (d, 2H), 7.28 (d, 2H), 4.68 (s, 2H), 3.41 (s, 2H), 2.22 (s, 6H). 
 b) N-&lsqb;N-(4-dimethylaminomethylbenzyloxycarbonyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(e)-1(h), except substituting 4-(N,N-dimethylamino)benzyl alcohol for 4-pyridylcarbinol in step (f) and N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide, the title compound was prepared as a white solid (186 mg, 87%). MS (ESI): 574.3 (M&plus;H) &plus; . 
 Example 111 
 Preparation of N-(N-benzyloxcarbonyl-L-norvalinyl)-N′-&lsqb;2-(2-benzyloxyphenyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 27(a)-27(c), except substituting N-benzyloxycarbonyl-L-norvaline for 2-(3-phenylphenyl)-4-methylpentanoic acid in step (c), the title compound was prepared as a white solid. MS (ESI): 559.0 (M&plus;H) &plus; . 
 Example 112 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting 4-methylimidazole-5-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (100 mg, 65%). MS (ESI): 474.3 (M&plus;H) &plus; . 
 Example 113 
 Preparation of N-&lsqb;N-&lsqb;4-(4-morpholinomethyhlbenzoyl&rsqb;-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 108(a)-108(c), except substituting morpholine for dimethylmaine in step (a), the title compound was prepared as a white solid (0.097 g, 51%). MS (ESI): 586.2 (M&plus;H) &plus; . 
 Example 114 
 Preparation of N-&lsqb;N-(2-methylnicotinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthylithiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 2-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.103 g, 60%). MS (ESI): 502.2 (M&plus;H) &plus; . 
 Example 115 
 Preparation of N-&lsqb;N-(6-methylnicotinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 6-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.134 g, 79%). MS (ESI): 502.2 (M&plus;H) &plus; . 
 Example 116 
 Preparation of N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-allylglycinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N-tert-butoxycarbonyl-L-allylglycine To a stirring solution of L-allylglycine (6.28 g, 54.5 mmol) in dioxane/water/1 N NaOH (110 mL/55 mL/55 mL ) at 0° C. was added di-tert-butyl dicarbonate (12.5 g, 57.2 mmol). After stirring for 30 min., the solution was concentrated and redissolved in 60 mL of water. A layer of ethyl acetate was added and the aqueous layer was acidified to pH 3 with 0.3 N KHSO 4 . The aqueous layer was extracted with ethyl acetate (2×). The organic layers were combined, washed with water (2×), dried (MgSO 4 ), filtered and concentrated to yield the title compound as a white solid (10.11 g, 86%). MS (ESI): 453.2 (2 M&plus;Na) &plus; . 
 b) N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-allylglycinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-allylglycine for N-tert-butoxycarbonyl-L-leucine in step (b) and 4-methylimidazole-5-carboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.112 g, 67%). MS (ESI): 475.1 (M&plus;H) &plus; . 
 Example 117 
 Preparation of N-(N-b-tert-butoxycarbonyl-L-tert-butylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) N-tert-butoxycarbonyl-L-b-tert-butylalanine Following the procedure of Example 116(a), except substituting L-tert-butylalanine for L-allylglycine, the title compound was prepared as a white solid (2.36 g, 70%). MS(ESI): 268.3 (M&plus;Na) &plus; . 
 b) N-(N-b-tert-butoxycarbonyl-L-tert-butylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (0.96 g, 100%). MS (ESI): 480.3 (M&plus;H) &plus; . 
 Example 118 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-b-tert-butoxycarbonyl-L-tert-butylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 8-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (160 mg, 82%). MS (ESI): 535.3 (M&plus;H) &plus; . 
 Example 119 
 Preparation of N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 4-methylimidazole-5-carboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.096 g, 58%). MS (ESI): 505.2 (M&plus;H) &plus; . 
 Example 120 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-b-tert-butoxycarbonyl-L-tert-butylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 4-methylimidazole-5-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (180 mg, 78%). MS (ESI): 488.2 (M&plus;H) &plus; . 
 Example 121 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-b-tert-butylalanyl)hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and picolinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.098 g, 62%). MS (ESI): 502.3 (M&plus;H) &plus; . 
 Example 122 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b), the title compound was prepared as a white solid (0.083 g, 46%). MS (ESI): 552.2 (M&plus;H) &plus; . 
 Example 123 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-allylglycinyl)hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-allylglycine for N-tert-butoxycarbonyl-L-leucine in step (b) and picolinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.141 g, 84%). MS (ESI): 472.2 (M&plus;H) &plus; . 
 Example 124 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-b-cyclopropylalanyl)hydrazide 
 a) N-tert-butoxycarbonyl-L-b-cyclopropylalanine Methyl Ester To a stirring solution of the compound of Example 116(a) (7.81 g, 36.3 mmol) in ether (100 mL) at 0° C. was added a solution of diazomethane (made from 10 eq of 1-methyl-3-nitro-1-nitrosoguanidine in ether (500 mL) and 40% NaOH (500 mL) at 0° C.). After stirring for 10 min., Pd(OAc) 2 (0.300 g) was added to the solution. After 20 min., the solution was concentrated and the residue was filtered through a short plug of silica gel to remove unused catalyst. Concentration of the solution yielded the title compound as a golden yellow oil (8.29 g, 99%). 1 H NMR (400 MHz, CDCl 3 ) d 5.17 (d, 1H), 4.39 (m, 1H), 3.73 (s, 3H), 1.66 (t, 2H), 1.44 (s, 9H), 0.68 (m, 1H), 0.49 (m, 2H), 0.08 (m, 1H). 
 b) N-tert-butoxycarbonyl-L-b-cyclopropylalanine Following the procedure of Example 1(g), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine methyl ester for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a golden yellow oil (6.37 g, 82%). MS (ESI): 252.3 (M&plus;Na) &plus; . 
 c) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-cyclopropylalanyl)hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and picolinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.114 g, 71%). MS (ESI): 486.1 (M&plus;H) &plus; . 
 Example 125 
 Preparation of N-&lsqb;N-(6-methylnicotinoyl)-L-b-cyclopropylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 6-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.097 g, 59%). MS (ESI): 500.1 (M&plus;H) &plus; . 
 Example 126 
 Preparation of N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-b-cyclopropylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 4-methylimidazole-5-carboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.095 g, 59%). MS (ESI): 489.1 (M&plus;H) &plus; . 
 Example 127 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b), the title compound was prepared as a white solid (0.138 g, 78%). MS (ESI): 536.2 (M&plus;H) &plus; . 
 Example 128 
 Preparation of N-&lsqb;N-(6-methylnicotinoyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 6-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.124 g, 73%). MS (ESI): 516.1 (M&plus;H) &plus; . 
 Example 129 
 Preparation of N-&lsqb;2-(N-cyclopropyl)-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-b-tert-butylalanyl)hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-b-tert-butoxycarbonyl-L-tert-butylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a), the title compound was prepared as a white solid (143 mg, 83%). MS (ESI): 485.1 (M&plus;H) &plus; . 
 Example 130 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-isoquinolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-b-tert-butoxycarbonyl-L-tert-butylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3-isoquinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (138 mg, 85%). MS (ESI): 535.1 (M&plus;H) &plus; . 
 Example 131 
 Preparation of N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropylmethyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (1.375 g, 76%). MS (ESI): 464.2 (M&plus;H) &plus; . 
 Example 132 
 Preparation of N-&lsqb;2-(N-cyclopropylmethyl-N-propylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-cyclopropyl propylamine for cis-2,6-dimethylmorpholine in step (a) and 6-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as an orange solid (84 mg, 33%). MS (ESI): 517.3 (M&plus;H) &plus; . 
 Example 133 
 Preparation of N-&lsqb;N-(6-methylnicotinoyl)-L-allylglycinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-allylglycine for N-tert-butoxycarbonyl-L-leucine in step (b) and 6-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared prepared as a white solid (0.097 g, 66%). MS (ESI): 486.1 (M&plus;H) &plus; . 
 Example 134 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-allylglycinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-allylglycine for N-tert-butoxycarbonyl-L-leucine in step (b), the title compound was prepared as a white solid (0.105 g, 74%). MS (ESI): 522.1 (M&plus;H) &plus; . 
 Example 135 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 2-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.151 g, 86%). MS (ESI): 536.3 (M&plus;H) &plus; . 
 Example 136 
 Preparation of N-&lsqb;N-(3-isoquinolinoyl)-L-b-cyclopropylalanyl&rsqb;-N′&lsqb;-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 3-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.145 g, 82%). MS (ESI): 536.1 (M&plus;H) &plus; . 
 Example 137 
 Preparation of N-&lsqb;N-(1-isoquinolinoyl)-L-b-cyclopropylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 1-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.143 g, 81%). MS (ESI): 536.1 (M&plus;H) &plus; . 
 Example 138 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(7-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 7-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.138 g, 78%). MS (ESI): 536.1 (M&plus;H) &plus; . 
 Example 139 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 8-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (120 mg, 73%). MS (ESI): 519.1 (M&plus;H) &plus; . 
 Example 140 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 4-methylimidazole-5-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (120 mg, 81%). MS (ESI): 472.1 (M&plus;H) &plus; . 
 Example 141 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-isoquinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3-isoquinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared obtained as a white solid (140 mg, 82%). MS (ESI): 519.2 (M&plus;H) &plus; . 
 Example 142 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (105 mg, 62%). MS (ESI): 483.2 (M&plus;H) &plus; . 
 Example 143 
 Preparation of N-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-norleucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and 4-methylimidazole-5-carboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.112 g,70%). MS (ESI): 491.1 (M&plus;H) &plus; . 
 Example 144 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-norleucinyl)hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and picolinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.114 g, 72%). MS (ESI): 488.2 (M&plus;H) &plus; . 
 Example 145 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-norleucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b), the title compound was prepared as a white solid (0.082 g, 47%). MS (ESI): 538.1 (M&plus;H) &plus; . 
 Example 146 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 2-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (150 mg, 81%). MS (ESI): 519.2 (M&plus;H) &plus; . 
 Example 147 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(1-isoquinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 1-isoquinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (130 mg, 87%). MS (ESI): 519.2 (M&plus;H) &plus; . 
 Example 148 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methoxypropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(h), except substituting N-isobutyl cyclopropylamine for cis-2,6-dimethylmorpholine in step (a) and 6-methyl-3-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (220 mg, 88%). MS (ESI): 517.2 (M&plus;H) &plus; . 
 Example 149 
 Preparation of N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropyl isobutylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-leucine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (1.01 g, 89%). MS (ESI): 466.3 (M&plus;H) &plus; . 
 Example 150 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(7-quinolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 7-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.139 g, 80%). MS (ESI): 552.2 (M&plus;H) &plus; . 
 Example 151 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 2-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.158 g, 91%). MS (ESI): 552.2 (M&plus;H) &plus; . 
 Example 152 
 Preparation of N-&lsqb;N-(1-isoquinolinoyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 1-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.143 g, 82%). MS (ESI): 552.2 (M&plus;H) &plus; . 
 Example 153 
 Preparation of N-&lsqb;N-(3-isoquinolinoyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-tert-butoxycarbonyl-L-leucine in step (b) and 3-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.130 g, 75%). MS (ESI): 552.2 (M&plus;H) &plus; . 
 Example 154 
 Preparation of N-&lsqb;N-(6-methylnicotinoyl)-L-norleucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and 6-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.109 g, 67%). MS (ESI): 502.2 (M&plus;H) &plus; . 
 Example 155 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(7-quinolinoyl)-L-norleucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and 7-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.104 g, 59%). MS (ESI): 538.1 (M&plus;H) &plus; . 
 Example 156 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl-L-norleucinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and 2-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.153 g, 87%). MS (ESI): 538.1 (M&plus;H) &plus; . 
 Example 157 
 Preparation of N-&lsqb;N-(1-isoquinolinoyl)-L-norleucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and 1-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.151 g, 86%). MS (ESI): 538.1 (M&plus;H) &plus; . 
 Example 158 
 Preparation of N-&lsqb;N-(3-isoquinolinoyl)-L-norleucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norleucine for N-tert-butoxycarbonyl-L-leucine in step (b) and 3-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.126 g, 72%). MS (ESI): 538.1 (M&plus;H) &plus; . 
 Example 159 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(5-hydroxymethylimidazol-4-ylcarbonyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 5-hydroxymehylimidazole-4-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (50 mg, 44%). MS (ESI): 488.2 (M&plus;H) &plus; . 
 Example 160 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-Quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide 
 a) N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropyl isobutylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-b-cyclopropylalanine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (1.01 g, 89%). MS (ESI): 466.3 (M&plus;H) &plus; . 
 b) N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 8-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (135 mg, 100%). MS (ESI): 521.2 (M&plus;H) &plus; . 
 Example 161 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-(6-methylnicotinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (85 mg, 79%). MS (ESI): 499.2 (M&plus;H) &plus; . 
 Example 162 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 4-methylimidazole-5-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (100 mg, 73%). MS (ESI): 474.2 (M&plus;H) &plus; . 
 Example 163 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 2-quinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (75 mg, 59%). MS (ESI): 521.2 (M&plus;H) &plus; . 
 Example 164 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (112 mg, 65%). MS (ESI): 485.3 (M&plus;H) &plus; . 
 Example 165 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)glycinyl&rsqb;hydrazide 
 a) N-(8-quinolinoyl)glycine Following the procedure of Example 102(f)-102(g), except substituting glycine methyl ester hydrochloride for L-leucine methyl ester in step (f), the title compound was prepared as a pale yellow solid (0.207 g, 95%). MS (ESI): 231.1 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)glycinyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and N-(8-quinolinoyl)glycine for N-(4-pyridylmethoxycarbonyl)-L-leucine, the title compound was prepared as a tan solid (0.028 g, 12%). MS (ESI): 482.1 (M&plus;H) &plus; . 
 Example 166 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(8-quinolinoyl)-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b), the title compound was prepared as a white solid (0.131 g, 74%). MS (ESI): 524.1 (M&plus;H) &plus; . 
 Example 167 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-quinolinoyl)-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b) and 2-quinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.135 g, 75%). MS (ESI): 524.1 (M&plus;H) &plus; . 
 Example 168 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-(N-picolinoyl-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b) and picolinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.126 g, 79%). MS (ESI): 474.2 (M&plus;H) &plus; . 
 Example 169 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b) and 6-methylnicotinic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.141 g, 85%). MS (ESI): 488.2 (M&plus;H) &plus; . 
 Example 170 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b) and 4-methylimidazole-5-carboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.098 g, 51%). MS (ESI): 477.1 (M&plus;H) &plus; . 
 Example 171 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(1-isoquinolinoyl)-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b) and 1-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.146 g, 82%). MS (ESI): 524.2 (M&plus;H) &plus; . 
 Example 172 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3-isoquinolinoyl)-L-norvalinyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting N-tert-butoxycarbonyl-L-norvaline for N-tert-butoxycarbonyl-L-leucine in step (b) and 3-isoquinolinecarboxylic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.138 g, 78%). MS (ESI): 524.2 (M&plus;H) &plus; . 
 Example 173 
 Preparation of (1S, 1′S)-N,N′-bis-&lsqb;4-&lsqb;1-(N-benzyloxycarbonylamino)-3-methylbutyllthiazol-2-ylcarbonyl&rsqb;hydrazide 
 a) N-benzyloxycarbonyl-L-leucinamide To a stirring solution of N-benzyloxycarbonyl-L-leucine (4.6 g, 17.3 mmol) in THF, cooled to −40° C., was added N-methylmorpholine (3.68 g, 36.4 mmol; 4.0 mL) and isobutyl chloroformate (2.37 g, 17.3 mmol; 2.25 mL). After stirring for 15 min, ammonia was bubbled through the solution for 5 min. The solution was warmed to room temperature, evaporated, and the residue was dissolved in ethyl acetate, washed with 0.1 N Hcl, and saturated brine, then dried (MgSO 4 ), filtered and evaporated to dryness to give the title compound as a white solid (4.58 g, 100%). 
 b) N-benzyloxycarbonyl-L-leucinethioamide A solution of the compound of Example 1(a) (4.58 g, 17.3 mmol) and Lawesson's reagent (4.21 g, 10.4 mmol) in THF was allowed to stir at room temperature for 16 h. The solution was concentrated and the residue was purified by flash chromatography on 230-400 mesh silica gel, eluting with 1:3 EtOAc/hexanes, to provide the title compound as a pale yellow solid (3.74 g, 77%). 
 c) (1S)-1-benzyloxycarbonylamino-1-(4-carboethoxythiazol-2-yl)-3-methylbutane The compound of Example 1(b) (2.20 g, 7.83 mmol) was dissolved in acetone (35 mL), cooled to −10° C., and ethyl bromopyruvate (1.68 g, 8.62 mmol, 1.08 mL) was added. After stirring for 1 h, the solution was poured into methylene chloride/water, then into saturated aqueous NaHCO 3 . The aqueous layer was extracted with methylene chloride and the combined organic layers were washed with saturated brine, dried (MgSO 4 ), filtered and concentrated. The residue was dissolved in methylene chloride, cooled to −20° C., pyridine (1.36 g, 17.2 mmol, 1.39 mL) and trifluroracetic anhydride (1.81 g, 8.62 mmol, 1.22 mL ) were added. After stirring for 1 h, the solution was washed with saturated squeous NaNCO 3 and saturated brine, then dired (MgSO 4 ), filtered, and concentrated. The residue was purified by flash chromatography on 90 g of 230-400 mesh silica gel, eluting with 1:3 ethyl acetate/hexanes, to provide the title compound as a pale yellow oil (2.36 g, 80%). 1 H NMR (400 MHz, CDCl 3 ) d 8.08 (s, 1H), 7.38 (m, 5H), 5.42 (s, 3H), 5.23-5.07 (m, 3H), 4.42 (q, 2H), 2.01-1.62 (m, 3H), 1.41 (t, 3H), 0.99 (d, 6H). 
 d) (1S)-benzyloxycarbonylamino-1-(4-hydrazinocarbonylthiazol-2-yl)-3-methylbutane Following the procedure of Example 1(d), except substituting (1S)-1-benzyloxycarbonylamino-1-(4-carboethoxythiazol-2-yl)-3-methylbutane for ethyl 2-(cis-2,6-dimethyl-4-morpholino)thiazole-4-carboxylate, the title compound was prepared as a pale yellow foam (2.01 g, 97%). 1 H NMR (400 MHz, CDCl 3 ) d 8.35 (bs, 1H), 8.03 (s, 1H), 7.37 (m, 5H), 5.29 (d, 1H), 5.14-5.09 (m, 3H), 4.07 (bs, 2H), 1.92-1.82 (m, 1H), 1.79-1.66 (m, 2H), 1.00 (d, 6H). 
 e) (1S)-1-benzyloxycarbonylamino-1-(4-carboxythiazol-2-yl)-3-methylbutane Following the procedure of Example 1(g), except substituting (1S)-1-benzyloxycarbonylamino-1-(4-carboethoxythiazol-2-yl)-3-methylbutane for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid. MS (ESI): 349.2 (M&plus;H) &plus; . 
 f) (1S, 1′S)-N,N′-bis-&lsqb;4-&lsqb;1-(N-benzyloxycarbonylamino)-3-methylbutyl&rsqb;thiazol-2-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting (1S)-1-benzyloxycarbonylamino-1-(4-hydrazinocarbonylthiazol-2-yl)-3-methylbutane for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and (1S)-1-benzyloxycarbonylamino-1-(4-carboxythiazol-2-yl)-3-methylbutane for N-(4-pyridylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (0.028 g, 59%). MS (ESI): 693.1 (M&plus;H) &plus; . 
 Example 174 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide 
 a) N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 1(a)-1(d) and 1(h), except substituting N-cyclopropyl isobutylamine for cis-2,6-dimethylmorpholine in step (a) and N-tert-butoxycarbonyl-L-b-tert-butylalanine for N-(4-pyridinylmethoxycarbonyl)-L-leucine in step (h), the title compound was prepared as a white solid (0.44 g, 100%). MS (ESI): 482.3 (M&plus;H) &plus; . 
 b) N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylnicotinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-btert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylnicotinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (70 mg, 66%). MS (ESI): 501.2 (M&plus;H) &plus; . 
 Example 175 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-methylimidazol-5-ylcarbonyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 4-methylimidazole-5-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (70 mg, 39%). MS (ESI): 490.2 (M&plus;H) &plus; . 
 Example 176 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(1-isoquinolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 1-isoquinolinecarboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (123 mg, 88%). MS (ESI): 535.3 (M&plus;H) &plus; . 
 Example 177 
 Preparation of N-&lsqb;N-(5-butylpicolinoyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 5-butylpicolinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (90 mg, 85%). MS (ESI): 541.3 (M&plus;H) &plus; . 
 Example 178 
 Preparation of N-&lsqb;2-(Ncyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylpicolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylpicolinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (170 mg, 86%). MS (ESI): 499.2 (M&plus;H) &plus; . 
 Example 179 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-fluorobenzoyl)-L-leucinyl)hydrazide Following the procedure of Example 56(a)-56(b), except substituting 4-fluorobenzoic acid for picolinic acid in step (b), the title compound was prepared as a white solid (88 mg, 97%). MS (ESI): 488.2 (M&plus;H) &plus; . 
 Example 180 
 Preparation of N-&lsqb;N-(4-fluorobenzoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 59(a)-59(d), except substituting 4-fluorobenzoic acid for 8-quinolinecarboxylic acid in step (d), the title compound was prepared as a white solid (0.113 g, 69%). MS (ESI): 505.1 (M&plus;H) &plus; . 
 Example 181 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-b-tert-butylalanyl&rsqb;hydrazide 
 a)-L-b-tert-butylalanine Methyl Ester Hydrochloride To a suspension of L-b-tert-butylalanine (2.0 g, 13.8 rnrnol) in 2,2-dimethoxypropane (75 mL) was added concentrated hydrochloric acid (12 mL). After standing at room temperature for 16 h, the solution was concentrated, redissolved in ethyl acetate and washed with 7.5% Na 2 CO 3 (2×). The organic layer was dried (MgSO 4 ), filtered and concentrated to yield the free base (1.3 g, 8.2 mmol). This was dissolved in ether and HCl (8.2 mL, 1.0 M in ether) added. The white precipitate was collected by filtration yield the title compound as a white solid (1.32 g, 49%). MS (ESI): 159.7 (M&plus;H) &plus; . 
 b) N-(2-pyridinylmethoxycarbonyl)-L-b-tert-butylalanine Following the procedure of Example 1(e)-5(g), except substituting L-b-tert-butylalanine methyl ester hydrochloride for L-leucine methylo ester hydrochloride in step (e) and 2-pyridylcarbinol for 4-pyridylcarbinol in step (f), the title compound was prepared as a white solid (0.55 g, 100%). MS (ESI): 281.3 (M&plus;H) &plus; . 
 c) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 1(h), except substituting N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(cis-2,6-dimethyl-4-morpholino)thiazol-4-ylcarbonyl&rsqb;hydrazide and N-(2-pyridinylmethoxycarbonyl)-L-b-tert-butylalanine for N-(4-pyridylmethoxycarbonyl)-L-leucine, the title compound was prepared as a white solid (0.155 g, 47%). MS (ESI): 532.2 (M&plus;H) &plus; . 
 Example 182 
 Preparation of N-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 181(a)-181(c), except substituting 2-methyl-3-pyridylcarbinol for 2-pyridylcarbinol in step (b), the title compound was prepared as a white solid (0.169 g, 67%). MS (ESI): 546.2 (M&plus;H) &plus; . 
 Example 183 
 Preparation of N-&lsqb;2-(1-naphthyl)thiazol-1-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-b-cyclopropylalanyl&rsqb;hydrazide 
 a)-L-b-cyclopropylalanine Methyl Ester Hydrochloride Following the procedure of Example 181(a), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine methyl ester for L-b-tert-butylalanine, the title compound was prepared as a white solid (2.2 g, 30%). MS (ESI): 144.0 (M&plus;H) &plus; . 
 b) N-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(2-pyridinylmethoxycarbonyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 181(b)-181(c), except substituting L-b-cyclopropylalanine methyl ester hydrochloride for L-b-tert-butylalanine methyl ester hydrochloride in step (b), the title compound was prepared as a white solid (0.147 g, 61%). MS (ESI): 516.1 (M&plus;H) &plus; . 
 Example 184 
 Preparation of N-&lsqb;N-(2-methyl-3-pyridinylmethoxycarbonyl)-L-b-cyclopropylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 181(a)-181(c), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine methyl ester for L-b-tert-butylalanine in step (a) and 2-methyl-3-pyridylcarbinol for 2-pyridylcarbinol in step (b), the title compound was prepared as a white solid (0.159 g, 65%). MS (ESI): 530.2 (M&plus;H) &plus; . 
 Example 185 
 Preparation of N-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-b-cyclopropylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 181(a)-181(c), except substituting N-tert-butoxycarbonyl-L-b-cyclopropylalanine methyl ester for L-b-tert-butylalanine in step (a) and 6-methyl-3-pyridylcarbinol for 2-pyridylcarbinol in step (b), the title compound was prepared as a white solid (0.169 g, 69%). MS (ESI): 530.2 (M&plus;H) &plus; . 
 Example 186 
 Preparation of N-&lsqb;N-(6-methyl-3-pyridinylmethoxycarbonyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 181(a)-181(c), except substituting 6-methyl-3-pyridylcarbinol for 2-pyridylcarbinol in step (b), the title compound was prepared as a white solid (0.194 g, 77%). MS (ESI): 546.2 (M&plus;H) &plus; . 
 Example 187 
 Preparation of N,N′-bis-&lsqb;2-(1-naphthyl)thiazol-4-ylcarbonyl&rsqb;hydrazide 
 a) ethyl 2-(1-naphthyl)thiazole-4-carbohydrazide Following the procedure of Example 3(a)-3(c) and 3(e), except substituting 1-naphthylboronic acid for 4-methyl-1-naphthylboronic acid in step (e), the title compound was prepared as a pale yellow solid. MS (ESI): 270.1 (M&plus;H) &plus; . 
 a) ethyl 2-(1-naphthyl)thiazole-4-carbohydrazide Following the procedure of Example 1(g), except substituting ethyl 2-(1-naphthyl)thiazole-4-carbohydrazide for N-(4-pyridinylmethoxycarbonyl)-L-leucine methyl ester, the title compound was prepared as a white solid. MS (ESI): 256.0 (M&plus;H) &plus; . 
 Example 188 
 Preparation of N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-&lsqb;2-(1,8-naphthyridinoyl)&rsqb;-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 1,8-naphthyridine-2-carboxylic acid for picolinic acid in step (b), the title compound was prepared as a white solid (100 mg, 59%). MS (ESI): 520.2 (M&plus;H) &plus; . 
 Example 189 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3,4-difluorobenzoyl)-L-b-cyclopropylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-cyclopropylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3,4-difluorobenzoic acid for picolinic acid in step (b), the title compound was prepared as a white solid (208 mg, 100%). MS (ESI): 506.1 (M&plus;H) &plus; . 
 Example 190 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(4-flluorobenzoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 4-fluorobenzoic acid for picolinic acid in step (b), the title compound was prepared as a white solid (130 mg, 70%). MS (ESI): 490.2 (M&plus;H) &plus; . 
 Example 191 
 Preparation of N-&lsqb;N-(5-butylpicolinoyl)-L-leucinyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 5-butylpicolinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (100 mg, 63%). MS (ESI): 529.3 (M&plus;H) &plus; . 
 Example 192 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3,4-dimethoxybenzoyl)-L-leucinyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-leucinyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3,4-dimethoxybenzoic acid for picolinic acid in step (b), the title compound was prepared as a white solid (130 mg, 84%). MS (EIS): 532.2 (M&plus;H) &plus; . 
 Example 193 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3,4-difluorobenzoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3,4-difluorobenzoic acid for picolinic acid in step (b), the title compound was prepared as a white solid (120 mg, 78%). MS (ESI): 522.2 (M&plus;H) &plus; . 
 Example 194 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(3,4-dimethoxybenzoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 3,4-dimethoxybenzoic acid for picolinic acid in step (b), the title compound was prepared as a white solid (73 mg, 51%). MS (ESI): 546.3 (M&plus;H) &plus; . 
 Example 195 
 Preparation of N-&lsqb;N-(5-butylpicolinoyl)-L-b-tert-butylalanyl&rsqb;-N′-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 5-butylpicolinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (120 mg, 77%). MS (ESI): 543.2 (M&plus;H) &plus; . 
 Example 196 
 Preparation of N-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;-N′-&lsqb;N-(6-methylpicolinoyl)-L-b-tert-butylalanyl&rsqb;hydrazide Following the procedure of Example 56(a)-56(b), except substituting N-(N-tert-butoxycarbonyl-L-b-tert-butylalanyl)-N′-&lsqb;2-&lsqb;N-cyclopropyl-N-(2-methylpropyl)amino&rsqb;thiazol-4-ylcarbonyl&rsqb;hydrazide for N-&lsqb;2-(N-cyclopropyl-N-cyclopropylmethylamino)thiazol-4-ylcarbonyl&rsqb;-N′-(N-tert-butoxycarbonyl-L-leucinyl)hydrazide in step (a) and 6-methylpicolinic acid for picolinic acid in step (b), the title compound was prepared as a white solid (104 mg, 72%). MS (ESI): 501.3 (M&plus;H) &plus; . The above specification and Examples fully disclose how to make and use the compounds of the present invention. However, the present invention is not limited to the particular embodiments described hereinabove, but includes all modifications thereof within the scope of the following claims. The various references to journals, patents and other publications which are cited herein comprise the state of the art and are incorporated herein by reference as though fully set forth.