English:
[0007] Genetic evidence indicates that factor XI is not required for normal homeostasis, implying a superior safety profile of the factor XI mechanism compared to competing antithrombotic mechanisms. In contrast to hemophilia A (factor VIII deficiency) or hemophilia B (factor IX deficiency), mutations of the factor XI gene causing factor XI deficiency (hemophilia C) result in only a mild to moderate bleeding diathesis characterized primarily by postoperative or posttraumatic, but rarely spontaneous hemorrhage. Postoperative bleeding occurs mostly in tissue with high concentrations of endogenous fibrinolytic activity (e.g., oral cavity, and urogenital system). The majority of the cases are fortuitously identified by preoperative prolongation of APTT (intrinsic system) without any prior bleeding history.
[0023] In a first aspect, the present invention provides, inter alia, a compound of Formula (I):
[0024] A is C3.7 cycloalkyl substituted with 0-1 R1 and 0-2 R2, C3-7 cycloalkenyl substituted with 0-1 R1 and 0-2 R2, phenyl substituted with 0-1 R1 and 0-3 R2, naphthyl substituted with 0-1 R1 and 0-3 R2, or a 5- to 12-membered heterocycle comprising: carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted 0-1 R1 and 0-3 R2;
[0025] X1, X2, X3, and X4, are independently CR3, CR4, N, NR6, N→O, or C(O); provided that at least one of X1, X2, X3, and X4 is CR3; [0026] X5 is N, NR6 or N→O;
[0034] alternately, when R1 and R2 are substituted on adjacent ring atoms, they can be taken together with the ring atoms to which they are attached to form a 5- to 7-membered carbocycle or heterocycle comprising: carbon atoms and 0-4 heteroatoms selected from N, O, and S(O)p, wherein said carbocycle or heterocycle is substituted with 0-2 R2b;
[0048] alternatively, R7 and R8, when attached to the same nitrogen, combine to form a 5- to 10-membered heterocycle comprising: carbon atoms and 0-2 additional heteroatoms selected from N, O, and S(O)P; wherein said heterocycle is substituted with 0-2 Rd; [0049] R8a is, independently at each occurrence, R7, OH, Cι_6 alkyl,
[0052] alternatively, R8 and R9, when attached to the same nitrogen, combine to form a 5- to 10-membered heterocycle comprising: carbon atoms and 0-2 additional heteroatoms selected from N, O, and S(O)Pj wherein said heterocycle is substituted with 0-2 Rd;
[0069] n, at each occurrence, is selected from 0, 1, 2, 3, and 4;
[0070] p, at each occurrence, is selected from 0, 1, and 2; and
[0071] r, at each occurrence, is selected from 0, 1, 2, 3, and 4; and
[0072] s, at each occurrence, is selected from 1, 2, 3, and 4.
[0089] R10 is H; and
[0090] R11 is Cι-6 alkyl, -(CH2)r-C(O)NR8R9, -CH2OBn, -CH2SBn, -(CH2)S- cyclohexyl substituted with 0-2 R1 lb, -(CH2)s-ρhenyl substituted with 0-2 R1 lb, - (CH2)s-naphthyl substituted with 0-2 Rl lb, -(CH2)s-5-to 10-membered heteroaryl substituted with 0-1 R1 lb; wherein said heteroaryl selected from thiazolyl, imidazolyl, pyridyl, indolyl benzimidazolyl, and benzothiazolyl.
[00109] alternately, when R1 and R2 are substituted on adjacent ring atoms, they can be taken together with the ring atoms to which they are attached to form a 5- to 7-membered carbocycle or heterocycle comprising: carbon atoms and 0-4 heteroatoms selected from N, O, and S(O)p, wherein said carbocycle or heterocycle is substituted with 0-2 R2b;
[00112] alternately, when two R3a groups are substituted on adjacent atoms, they can be taken together with the atoms to which they are attached to form a C3-10 carbocycle substituted with 0-2 R3d or a 5- to 10-membered heterocycle comprising: carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted with 0-2 R3d;
[00123] alternatively, R7 and R8, when attached to the same nitrogen, combine to form a 5- to 10-membered heterocycle comprising: carbon atoms and 0-2 additional heteroatoms selected from N, O, and S(O)p5 wherein said heterocycle is substituted with 0-2 Rd;
[00128] R10 is, independently at each occurrence, H, Cι_6 alkyl substituted with 0-2 R10a, -(CH2) phenyl substituted with 0-3 Rd, or -(CH2)r-5- to 10-membered heterocycle comprising carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted with 0-3 Rd; [00129] R10a is, independently at each occurrence, H, =O, C1.4 alkyl, ORa
[00144] r, at each occurrence, is selected from 0, 1, 2, 3, and 4; and
[00145] s, at each occurrence, is selected from 1, 2, 3, and 4.
[00158] R10 is H; and
[00159] R11 is -(CH2)r-C(O)NR8R9, -CH2OBn, -CH2SBn, -(CH2)s-cyclohexyl substituted with 0-2 Rl lb, -(CH2)s-ρhenyl substituted with 0-2 Rl lb, -(CH2)s-naphthyl substituted with 0-2 Rl lb, -(CH2)s-5-to 10-membered heteroaryl substituted with 0-1 R1 lb; wherein said heteroaryl selected from thiazolyl, imidazolyl, pyridyl, indolyl benzimidazolyl, and benzothiazolyl.
[00173] In a fifteenth aspect, the present invention provides a compound selected from the exemplified examples or stereoisomers or pharmaceutically acceptable salts, solvates, or prodrugs thereof.
[00176] X is C, CH, or N;
[00188] alternately, when two R3a groups are substituted on adjacent atoms, they can be taken together with the atoms to which they are attached to form a C3.10 carbocycle substituted with 0-2 R3d, or a 5- to 10-membered heterocycle comprising: carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted with 0-2 R3d;
[00210] R10 is, independently at each occurrence, H, Cχ-6 alkyl substituted with 0-3 R10a, C2-6 alkenyl substituted with 0-3 R10a, C2-6 alkynyl substituted with 0-3 R10a, -(CH2)r-C3_io carbocycle substituted with 0-3 Rd, or -(CH )r-5- to 10- membered heterocycle comprising carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted with 0-3 Rd; [00211] R10a is, independently at each occurrence, H, =O, C1-4 alkyl, ORa SRa F, CF3, CN, NO2, -C(O)Ra, -C(O)ORa, -C(O)NR7R8, -NR7C(O)Rb, -S(O)pNR8R9, -NR8S(O)pRc, -S(O)Rc, or -S(O)2Rc;
[00223] alternately, R13 can be taken together with R10 to form a 5- to 10- membered heterocycle comprising: carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted with 0-2 Rd;
[00233] Rg is, independently at each occurrence, H, C^ _g alkyl, or -(CH2)n-phenyl;
[00234] n, at each occurrence, is selected from 0, 1, 2, 3, and 4;
[00235] p, at each occurrence, is selected from 0, 1, and 2; and
[00236] r, at each occurrence, is selected from 0, 1, 2, 3, and 4; and
[00237] s, at each occurrence, is selected from 1, 2, 3, and 4.
[00249] R6 is, independently at each occurrence, H, or Cι_6 alkyl substituted with 0-2 R6a;
[00251] R11 is Cι_6 alkyl substituted with 0-3 R1 la -(CH2)r-phenyl substituted with 0-3 Rl l , or -(CH2)r-5- to 10-membered heterocycle comprising: carbon atoms and 1-4 heteroatoms selected from N, O, and S(O)p, wherein said heterocycle is substituted with 0-3 R1 lb; and
[00252] R12 is H, F, CM haloalkyl, Cι_6 alkyl, phenyl, or benzyl.
[00276] In another embodiment, the present invention also provides the use of a compound of the present invention or a pharmaceutically acceptable salt, solvate, or prodrug form thereof, for the manufacture of a medicament for the treatment of a thromboembolic and/or inflarnmatory disorder.
[00277] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. This invention encompasses all combinations of preferred aspects of the invention noted herein. It is understood that any and all embodiments of the present invention may be taken in conjunction with any other embodiment or embodiments to describe additional more preferred embodiments. It is also to be understood that each individual element of the preferred embodiments is its own independent preferred embodiment. Furthermore, any element of an embodiment is meant to be combined with any and all other elements from any embodiment to describe an additional embodiment.
[00291] Preferred 5 to 10 membered heterocycles include, but are not limited to, pyridinyl, furanyl, thienyl, pyrrolyl, pyrazolyl, pyrazinyl, piperazinyl, piperidinyl, imidazolyl, imidazolidinyl, indolyl, tetrazolyl, isoxazolyl, morpholinyl, oxazolyl, oxazolidinyl, tetrahydrofuranyl, thiadiazinyl, thiadiazolyl, thiazolyl, triazinyl, triazolyl, benzimidazolyl, lH-indazolyl, benzofuranyl, benzothiofuranyl, benztetrazolyl, benzotriazolyl, benzisoxazolyl, benzoxazolyl, oxindolyl, benzoxazolinyl, benzthiazolyl, benzisothiazolyl, isatinoyl, isoquinolinyl, octahydroisoquinolinyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, isoxazolopyridinyl, quinazolinyl, quinolinyl, isothiazolopyridinyl, thiazolopyridinyl, oxazolopyridinyl, imidazolopyridinyl, and pyrazolopyridinyl.
[00305] "Stable compound" and "stable structure" are meant to indicate a compound that is sufficiently robust to survive isolation to a useful degree of purity from a reaction mixture, and formulation into an efficacious therapeutic agent. It is preferred that compounds of the present invention do not contain a N-halo, S(O)2H, or S(O)H group.
[00307] As used herein, "treating" or "treatment" cover the treatment of a disease-state in a mammal, particularly in a human, and include: (a) preventing the disease-state from occurring in a mammal, in particular, when such mammal is predisposed to the disease-state but has not yet been diagnosed as having it; (b) inhibiting the disease-state, i.e., arresting it development; and/or (c) relieving the disease-state, i.e., causing regression of the disease state.
[00308] "Therapeutically effective amount" is intended to include an amount of a compound of the present invention that is effective when administered alone or in combination to inhibit factor XIa and/or plasma kallikrein. "Therapeutically effective amount" is also intended to include an amount of the combination of compounds claimed that is effective to inhibit factor XIa and/or plasma kallikrein. The combination of compounds is preferably a synergistic combination. Synergy, as described, for example, by Chou and Talalay, Adv. Enzyme Regul 1984, 22:27-55, occurs when the effect (in this case, inhibition of factor XIa and/or plasma kallikrein) of the compounds when administered in combination is greater than the additive effect of the compounds when administered alone as a single agent. In general, a synergistic effect is most clearly demonstrated at sub-optimal concentrations of the compounds. Synergy can be in terms of lower cytotoxicity, increased antithrombotic and/or anti-inflammatory effect, or some other beneficial effect of the combination compared with the individual components.
[00313] All references cited herein are hereby incorporated in their entirety herein by reference. Methods for synthesis of a large variety of substituted pyridine and pyridone compounds useful as starting materials for the preparation of compounds of the present invention are well known in the art and have been extensively reviewed. (For examples of methods useful for the preparation of pyridine and pyridone starting materials see: Kxohhke, F. Synthesis, 1976, 1.; Pyridine and Its Derivatives. In The Chemistry of Heterocyclic Compounds, Abramovitch, R.A., Ed.; John Wiley and Sons: New York, 1974; Vol 14; Supplemental 1-4.; Comprehensive Heterocyclic Chemistry, Vol. 2, Boulton, A J. and McKillop, A, Eds. Pergamon Press, New York, 1984, pp 165-524; Comprehensive Heterocyclic Chemistry, Vol. 5, McKillop, A, Ed. Pergamon Press, New York, 1996, pp 1-300). Methods for synthesis of a large variety of substituted pyrimidine and pyrimidone compounds useful as starting materials for the preparation of compounds of the present invention are well known in the art and have been extensively reviewed. (For examples of methods useful for the preparation of pyrimidine and pyrimidone starting materials see: The Pyrimidines. In The Chemistry of Heterocyclic Compounds, Taylor, E.C., Ed.; John Wiley and Sons: New York, 1993; Vol 52).
[00320] Alternately, pyridine and pyridone compounds of this invention can be prepared as shown in Scheme 5. Compound 5c can be prepared in two steps from β- ketophosphonate 5a as described Scheme 4. Selective O-alkylation as described by Rao (Rao, J. M., et. al Tetrahedron, 1989, 5(22), 7093 and references cited there in) can be achieved with silver carbonate and an alkyl iodide, such as methyl iodide, i a solvent, such as benzene or chloroform, to give 5d. Alternatively, 5c can be treated with phosphorus oxychloride to give chloropyridine 5e. Dibromination of 5d/5e with NBS and subsequent reaction with morpholine at elevated temperatures followed by hydrolysis gives aldehydes 5f and 5g which can be converted to 5j and 5k, respectively, as described in Scheme 1. The chloro compound 5k is converted to the amine 51 via a modification of the procedure described by Buchwald (Buchwald, S. L. et al, Tetrahedron Letters, 1997, 35(36), 6363). After demethylation of 5h with HCI or BBr3, the amine is converted to the imine via transimination with benzophenone imine according to a modified procedure described by O'Donnell (O'Donnell, M.J., Polt, R.L. J. Org. Chem., 1982, 47, 2663). Deprotonation of the pyridone with a base such as sodium hydride in a solvent such as THF or DMF and quenching with an alkyl halide, such as methyl iodide, gives the N-alkyl derivative. Following hydrolysis of the imine with aqueous HCI, the amine is coupled with carboxylic acid If employing suitable amide coupling reagents as described in Scheme 1 to yield 5m. Further manipulation of functional groups on A and R3 using methods known to one skilled in the art of organic synthesis will give additional compounds of the invention.
[00321] Representative examples of manipulation of functional groups on R3 using methods known to one skilled in the art of organic synthesis are shown in Scheme 6. Heating 6a and 6b/6c with hydrazine monohydrate in rc-butanol gives the 3-aminoindazole 6d and the 3-hydroxy indazole 6e, respectively. Reacting 6a with acetohydroxamic acid and potassium fert-butoxide in DMF according to a modified procedure described by Palermo (Palermo, M.G. Tetrahedron Letters, 1996, 37(17), 2885) provides 3-aminobenzisoxazole 6f. Alternately, heating 6a with formamidine acetate or acetamidine acetate in DMA, according to a modified procedure described by Lam (Lam, P.Y. S. et al , J. Med. Chem. 2003, 46, 4405.) gives 4-amino quinazolines 6g and 6h. Quinazolinone 6k may be prepared similarly by heating the corresponding anthranilic acid derivatives 6i with formamide as described by Alexandre et al.(Tet. Lett. 2002 43, 3911). Alternatively, quinazolinone 6k can be prepared by heating 6j with ammonium acetate and frimethylorthoformate according to a modified procedure from published WO patent WO2005/012264.
[00328] Representative examples of manipulation of functional groups on R3 using methods known to one skilled in the art of organic synthesis are shown in Scheme 12. Fluoropyridhie 12a can be displaced with amines, such as ammonium hydroxide, to give ammopyridine 12b, alkoxides, such as sodium methoxide, to give 12c, or sodium hydroxide to give 12d according to a modified procedures described by Queguiner (Queguiner, G. et al. J. Org. Chem., 1988, 53, 2740.) Scheme 12
[00329] Representative examples of this invention when R3 is a pyrimidine ring system are shown in Schemes 13 and 14. Condensation of amidine 13b, which can be synthesized from cyanopyridine 13a via the Pinner reaction, with an appropriately substituted propiolate can provide pyrimidone 13c. Pyrimidone 13c can be converted to the aminopyrimidine 13d in two steps. A regioisomeric pyrimidine synthesis is described in Scheme 14. The β-ketonitrile 14b can be prepared from the acid 14a according to a modified procedure described by Katritzky (Katritzky, A. R. et al. J. Org. Chem., 2003, 68, 4932). Condensation of 14b with formamide and ammonia according to a modified procedure of Hirota (Hirota, T. et al. Synthesis, 1991, 303.) can provide ammopyrimidine 14c. The β-ketonitrile 14b can also be used to synthesize pyrazoles (Watson, S.P. et al. Tetrahedron Letters, 1997, 38, 9065.)
[00343] To a cooled (0 °C) suspension of solid 2 (35.5 g) in CH2C12 (500 mL) was added sat. NaHCO3 (300 mL). The suspension was stirred vigorously to dissolve most of the solid. The layers were separated and the aqueous layer was extracted with CH2C12 (200 mL). The combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated to give an orange liquid weighing 28 g. Column chromatography on silica gel (0-10% ethyl acetate in CH C1 and then 15:1 CH2Cl2:ethyl acetate) yielded 13.0 g of 3A as a white solid. Solid 1 was neutralized as described in the above procedure to give an additional 17.4 g of 3 A as a white solid. A total of 30.4 g (44%) of 3A was obtained. *H-NMR (400 MHz, CDC13) δ:
[00354] 7C. [(S)-2-Phenyl-l-(4-phenyl-pyrimidin-2-yl)-ethyl]-carbamic acid tert-b tyl ester: 7A (57 mg, 0.15 mmol), 7B (16 mg, 0.12 mmol), and Na2CO3 (31 mg, 0.30 mmol) were dissolved in acetonitrile and heated to 120 °C for 40 min using microwave irradiation. The reaction was cooled to rt and filtered. The filtrate was dried in vacuo to yield 75 mg (100%) of 7C which was carried onto the next step without further purification. MS 276.1 (M+l)+. [00355] 7D. (S)-2-Phenyl-l-(4-phenylpyrimidin-2-yI)ethanamine: 7C (56 mg, 0.15 mmol) was dissolved in CH2CI2 (2.7 mL) and treated with TFA (0.3 mL, 10% v/v) for 24 h at rt. The solvent and TFA were evaporated in vacuo and the residue redissolved in MeOH. The MeOH was evaporated to yield 59 mg (100%) of 7D. MS 276.1 (M+l)+.
[00358] 8A: [(S)-l-(6-Oxo-4-phenyl-l,6-dihydro-pyrimidin-2-yl)-2-phenyl- ethylj-carbamic acid tert-b tyl ester: 7A (50 mg, 0.13 mmol), ethyl 3- phenylpropiolate (46 mg, 0.26 mmol), and Hunig's base (34 mg, 0.26 mmol) were dissolved in EtOH (1 mL) and heated to reflux for 3 d. The reaction was cooled to rt and the solvent evaporated to dryness in vacuo. The residue was re-dissolved in MeOH/H2O (9:1) containing 0.1% TFA and isolated by prep HPLC to yield 16 mg of the desired product (31% yield). MS 392.1 (M+H)+.
[00359] 8B. Example 8: 8A (16 mg, 0.041 mmol) was converted to Example 8 using the procedures described in 7D-F with the exception that HOAt was used in place of HOBt. H NMR (500 MHz, d4-MeOH) δ 1.05 (m, 2H) 1.39 (m, 2H) 1.56
[00361] 13A. 4-Aminomethyl-cyclohexanecarboxylic acid {2-phenyl-l-[4- (l-triisopropylsilanyl-l£T-pyrrol-3-yI)-pyridin-2-yl]-ethyl}-amide, bistrifluoroacetic acid salt: This compound was prepared from 3D following the procedures described in example 3E using l-(Triisopropylsilyl)pyrrole-3 -boronic acid in place of 3-(methoxycarbonyl)phenylboronic acid to give 13 A (0.013 g, 16%) as a brown residue. MS 559.3 (M+H)+.
[00385] A solution of the bis-TFA salt of the cyclohexyl methylamine derivative (0.028 g, 0.042 mmol) and BBr3 (1.0 M in CH2C12 , 0.42 mL, 0.42 mmol) in CH2C (1 mL) was heated at 60 °C. After 2h, the reaction was cooled to 0 °C, quenched with MeOH, and concentrated. Prep. HPLC (21.2 x 100 mm, 8 min. gradient, 20 tol00% B, 20 mL/min.) afforded Example 35 (0.008 g, 35%) as a pink solid. 1H NMR (500 MHz, CD3OD) δ: 0.96-1.09 (m, 2 H), 1.27-1.46 (m, 2 H), 1.51- 1.62 (m, 2 H), 1.81-1.85 (m, 3 H), 2.15-2.22 (m, 1 H), 2.76 (d, J = 7.2 Hz, 2 H), 3.02 (dd, J = 9.9 Hz, 13.7 Hz, 1 H), 3.23 (dd, J = 6.0 Hz, 13.7 Hz, 1 H), 5.11 (dd, J = 6.0 Hz, 9.9 Hz, 1 H), 6.62 (s, 2 H), 7.18-7.31 (m, 5 H), 7.46-7.51 (m, 3 H), 7.60-7.62 (m, 2 H). HRMS m/z Calc'd for C27H32N3O2 (M + H)+: 430.2495. Found 430.2497.
[00390] 37A. 2-chloro-6-methyl-4-phenylpyridine: A suspension 6-methyl- 4-phenyl-lH-pyridin-2-one (0.185 g, 1.0 mmol) and POCl3 (0.56 mL, 6 mmol) in DMF (1 mL) was heated to 110 °C. After 1.5 h, the reaction was cooled to rt, quenched with water and extracted with EtOAc. The combined organic layers were washed with sat. NaΗCθ3, brine, dried over Na2SO , filtered, and concentrated. Column chromatography on silica gel (0-10% EtOAc/Hexane) provided 37A (0.143 g, 70%) as a yellow oil. MS 204.1 (M + H)+ and 206.1 (M+2+H)+.
[00393] 37D. Example 37: To a sealable tube was added 37C (0.045 g, 0.082 mmol), benzophenone imine (0.028 mL, 0.16 mmol), Pd(OAc)2 (0.0018 g, 0.0082 mmol), BINAP (0.0077 g, 0.012 mmol),Cs2CO3 (0.064 g, 0.2 mmol) and DMSO (0.55 mL). The mixture was degassed by bubbling argon for 10 min, the tube was sealed, and the reaction was heated at 85 °C. After 18h, the reaction was cooled to rt, poured into water and extracted with CH2C12 (3 x). The combined organic layers were washed with brine, dried over Na2SO4, filtered and concentrated to give the benzophenone imine derivative (0.10 g) as a yellow oil. MS 693.2 (M + H)+. [00394] The benzophenone imine derivative was dissolved in THF (1 mL) and
[00403] Example 52 was prepared from 3D following the procedures described in 3E using 3-carboxy-4-fluorophenylboronic acid in place of 3-
[00410] 58A. 6-[2-(l-Amino-2-phenyl-ethyl)-pyridm-4-yl]-lH-quinolin-4- one, £rø-trifluoroaeetic acid salt: A mixture of 57 (0.062 g, 0.074 mmol) in concentrated HCI (0.5 mL) and 1,2-dichloroethane (1.0 mL) was heated to 130 °C in a sealed tube. After 22 h, the reaction was concentrated. Prep. HPLC (Phenomenex Luna 5u 21.2 x 100 mm; 8 min. gradient, 20 tol00% B; 20 mL/min.) gave 58A (0.031 g, 92%) as a clear, colorless oil. MS 342.2 (M + H)+.
[00411] 58B. Example 58: To a solution of the oil in DMF (2 mL) was added Boc-tranexamic acid (0.023 g, 0.089 mmol), BOP reagent (0.0393 g, 0.089 mmol) and trietliylamine (0.041 mL, 0.30 mmol). After 2h, water was added and the reaction was extracted with EtOAc. The combined organic layers were washed with brine, dried over Na2S04, filtered and concentrated. Prep. HPLC (Phenomenex Luna 5u 21.2 x 100 mm; 8 min. gradient; 30 tol00% B; 20 mL/min.) gave 0.014 g of the amide as a white solid. The solid was dissolved in 50% TFA in CH2C12 (2 mL). After 1 h the reaction was concentrated. Prep. HPLC (Phenomenex Luna 5u 21.2 x 100 mm; 8 min. gradient; 20 to 100% B; 25 mL/min.) gave, after lyophilization, Example 58 (0.010 g, 16% over three steps) as a pale, yellow solid. 1H NMR (500 MHz, CD3OD) δ: 1.01-1.11 (m, 2 H), 1.34-1.45 (m, 2 H), 1.55-1.60 (m, 1 H), 1.75- 1.90 (m, 4 H), 2.28-2.33 ( , 1 H), 2.78 (d, J = 7.2 Hz, 2 H), 3.27-3.31 (m, 2 H), 5.35- 5.38 (m, 1 H), 6.53 (d, J = 7.2 Hz, 1 H), 7.22-7.30 (m, 5 H), 7.85 (d, J = 8.8 Hz, 1 H), 8.11-8.13 (m, 2 H), 8.16 (d, J = 7.2 Hz, 1 H), 8.23 (dd, J = 1.6 Hz, 8.8 Hz, 1 H), 8.69 (d, J = 6.1 Hz, 1 H), 8.76 (d, J = 1.6 Hz, 1 H). MS 481.4 (M + H)+.
[00412] Examples 9, 11-12, 14, 16-20, 24, 30-32, 41-51, 53, and 59-60 were prepared using procedures similar to those described above. Table 1 below summarizes representative examples of the compounds in the present invention.
[00441] The term thrombin inhibitors (or anti-thrombin agents), as used herein, denotes inhibitors of the serine protease thrombin. By inhibiting thrombin, various thrombin-mediated processes, such as thrombin-mediated platelet activation (that is, for example, the aggregation of platelets, and/or the granular secretion of plasminogen activator inhibitor- 1 and/or serotonin), endothelial cell activation, inflammatory reactions, and/or fibrin formation are disrupted. A number of thrombin inhibitors are known to one of skill in the art and these inhibitors are contemplated to be used in combination with the present compounds. Such inhibitors include, but are not limited to, boroarginine derivatives, boropeptides, heparins, hirudin and argatroban, including pharmaceutically acceptable salts and prodrugs thereof. Boroarginine derivatives and boropeptides include N-acetyl and peptide derivatives of boronic acid, such as C- terminal alpha-arninoboronic acid derivatives of lysine, or thine, arginine, homoarginine and corresponding isothiouronium analogs thereof. The term hirudin, as used herein, includes suitable derivatives or analogs of hirudin, referred to herein as hirulogs, such as disulfatohirudin.
[00453] Examples of suitable anti-obesity agents for use in combination with the compounds of the present invention include orlistat and aP2 inhibitors (such as those disclosed in WO00/59506).
[00457] Examples of suitable anti-ulcer and gastroesophageal reflux disease agents for use in combination with the compounds of the present invention include famotidine, ranitidine, and omeprazole.
[00460] The compounds of the present invention may also be used in diagnostic assays involving thrombin, Factor Vila, IXa, Xa, XIa, and/or plasma kallikrein. For example, the presence of thrombin, Factor Vila, LXa, Xa XIa, and/or plasma kallikrein in an unknown sample could be detemiined by addition of the relevant chromogenic substrate, for example S2366 for Factor XIa, to a series of solutions containing test sample and optionally one of the compounds of the present invention. If production of pNA is observed in the solutions containing test sample, but not in the presence of a compound of the present invention, then one would conclude Factor XIa was present.

中文:
[0007]遗传学证据表明XI因子并非正常稳态所需,提示XI因子机制的安全性优于竞争性抗血栓形成机制。与血友病A(VIII因子缺乏)或血友病B(IX因子缺乏)相反,导致XI因子缺乏(血友病C)的XI因子基因突变只引起轻度至中度出血素质(特征是原发于手术后或创伤后),但很少自发性出血。手术后出血多数发生在高浓度内源性纤维蛋白活性的组织(例如口腔和泌尿生殖系统)中。大多数病例既往无任何出血史,只是由于手术前APTT(内源系统)延长而被意外发现。
[0023]在第一方面,本发明提供(特别是)式(I)化合物:
[0024]A是被0-1个R1和0-2个R2取代的C3-7环烷基、被0-1个R1和0-2个R2取代的C3-7环烯基、被0-1个R1和0-3个R2取代的苯基、被0-1个R1和0-3个R2取代的萘基,或含碳原子和1-4个选自N、O和S(O)P的杂原子的5-至12-元杂环,其中所述杂环被0-1个R1和0-3个R2取代;
[0025]X1、X2、X3和X4独立地是CR3、CR4、N、NR6、N→O或C(O);前提是X1、X2、X3和X4中至少一个是CR3;
[0034]或者,当R1和R2在相邻的环原子上被取代时,它们可与它们连接的环原子结合在一起形成包含碳原子和0-4个选自N、O和S(O)p的杂原子的5-至7-元碳环或杂环,其中所述碳环或杂环被0-2个R2b取代;
[0048]或者,当R7和R8与同一氮原子连接时,它们结合形成含碳原子和0-2个选自N、O和S(O)p的另外杂原子的5-至10-元杂环,其中所述杂环被0-2个Rd取代;
[0052]或者,当R8和R9与同一氮原子连接时,它们结合形成含碳原子和0-2个选自N、O和S(O)p的另外杂原子的5-至10-元杂环,其中所述杂环被0-2个Rd取代;
[0069]每次出现时,n选自0、1、2、3和4;
[0070]每次出现时,p选自0、1和2;且
[0071]每次出现时,r选自0、1、2、3和4;且
[0072]每次出现时,s选自1、2、3和4。
[0089]R10是H;且
[0090]R11是C1-6烷基、-(CH2)rC(O)NR8R9、-CH2OBn、-CH2SBn、被0-2个R11b取代的-(CH2)s-环己基、被0-2个R11b取代的-(CH2)s-苯基、被0-2个R11b取代的-(CH2)s-萘基、被0-1个R11b取代的-(CH2)s-5-至10-元杂芳基;其中所述杂芳基选自噻唑基、咪唑基、吡啶基、吲哚基、苯并咪唑基和苯并噻唑基。
[00109]或者,当R1和R2在相邻的环原子上被取代时,它们可与它们连接的环原子结合在一起形成含碳原子和0-4个选自N、O和S(O)p的杂原子的5-至7-元碳环或杂环,其中所述碳环或杂环被0-2个R2b取代;
[00112]或者,当两个R3a基团在相邻的原子上被取代时,它们可与它们连接的原子结合在一起形成被0-2个R3d取代的C3-10碳环,或含碳原子和1-4个选自N、O和S(O)p的杂原子的5-至10-元杂环,其中所述杂环被0-2个R3d取代;
[00123]或者,当R7和R8连接于同一氮原子时,可结合形成含碳原子和0-2个选自N、O和S(O)p的另外杂原子的5-至10-元杂环;其中所述杂环被0-2个Rd取代;
[00128]R10每次出现时独立地是H、被0-2个R10a取代的C1-6烷基、被0-3个Rd取代的-(CH2)r-苯基,或含碳原子和1-4个选自N、O和S(O)p的杂原子的-(CH2)r-5-至10-元杂环,其中所述杂环被0-3个Rd取代;
[00144]r每次出现时,选自0、1、2、3和4;且
[00145]s每次出现时,选自1、2、3和4。
[00158]R10是H;且
[00159]R11是-(CH2)r-C(O)NR8R9、-CH2OBn、-CH2SBn、被0-2个R11b取代的-(CH2)s-环己基、被0-2个R11b取代的-(CH2)s-苯基、被0-2个R11b取代的-(CH2)s-萘基、被0-1个R11b取代的-(CH2)s-5-至10-元杂芳基;其中所述杂芳基选自噻唑基、咪唑基、吡啶基、吲哚基、苯并咪唑基和苯并噻唑基。
[00173]第十五方面,本发明提供选自示例性实施例的化合物或其立体异构体或药学上可接受的盐、溶剂合物或前体药物。
[00176]X是C、CH或N;
[00188]或者,当两个R3a基在相邻的原子上被取代时,它们可与它们连接的原子结合在一起形成被0-2个R3d取代的C3-10碳环,或含碳原子和1-4个选自N、O和S(O)p的杂原子的5-至10-元杂环,其中所述杂环被0-2个R3d取代;
[00210]R10每次出现时独立地是H、被0-3个R10a取代的C1-6烷基、被0-3个R10a取代的C2-6链烯基、被0-3个R10a取代的C2-6炔基、被0-3个Rd取代的-(CH2)r-C3-10碳环,或含碳原子和1-4个选自N、O和S(O)p的杂原子的-(CH2)r-5-至10-元杂环,其中所述杂环被0-3个Rd取代;
[00223]或者,R13可与R10结合在一起形成含碳原子和1-4个选自N、O和S(O)p的杂原子的5-至10-元杂环,其中所述杂环被0-2个Rd取代;
[00233]Rg每次出现时独立地是H、C1-6烷基或-(CH2)n-苯基;
[00234]n每次出现时,选自0、1、2、3和4;
[00235]p每次出现时,选自0、1和2;且
[00236]r每次出现时,选自0、1、2、3和4;且
[00237]s每次出现时,选自1、2、3和4。
[00249]R6每次出现时独立地是H或被0-2个R6a取代的C1-6烷基;
[00251]R11是被0-3个R11a取代的C1-6烷基、被0-3个R11b取代的-(CH2)r-苯基或含碳原子和1-4个选自N、O和S(O)p的杂原子的-(CH2)r-5-至10-元杂环,其中所述杂环被0-3个R11b取代;且
[00252]R12是H、F、C1-4卤代烷基、C1-6烷基、苯基或苄基。
[00276]在另一个实施方案中,本发明还提供本发明的化合物或其药学上可接受的盐、溶剂合物或前体药物形式在制备治疗血栓栓塞和/或炎性疾病的药物中的用途。
[00277]可在不脱离本发明的精神或基本属性的情况下,以其它具体形式实施本发明。本发明涵盖本文提及的本发明优选方面的所有组合。应理解的是可将任何及所有本发明的实施方案与任何其它一个或多个实施方案结合,以描述另外更多的优选实施方案。还应理解的是各具体优选实施方案的要素是其自身独立的优选实施方案。而且,意味着可将实施方案的任何要素与任何实施方案的任何及所有其它要素结合,以描述另外的实施方案。
[00291]优选的5至10元杂环包括,但不限于吡啶基、呋喃基、噻吩基、吡咯基、吡唑基、吡嗪基、哌嗪基、哌啶基、咪唑基、咪唑烷基、吲哚基、四唑基、异唑基、吗啉基、唑基、唑烷基、四氢呋喃基、噻二嗪基、噻二唑基、噻唑基、三嗪基、三唑基、苯并咪唑基、1H-吲唑基、苯并呋喃基、苯并噻吩基、苯并四唑基、苯并三唑基、苯并异唑基、苯并唑基、羟吲哚基、苯并唑啉基、苯并噻唑基、苯并异噻唑基、靛红酮基、异喹啉基、八氢异喹啉基、四氢异喹啉基、四氢喹啉基、异唑并吡啶基、喹唑啉基、喹啉基、异噻唑并吡啶基、噻唑并吡啶基、唑并吡啶基、咪唑并吡啶基和吡唑并吡啶基。
[00305]“稳定化合物”和“稳定结构”是指足够牢固以耐受从反应混合物中离析为有用纯度并配制成有效治疗剂的化合物。优选本发明化合物不含N-卤代、S(O)2H或S(O)H基团。
[00307]如在本文中所用的,“治疗”或“疗法”包括对哺乳动物特别是人疾病状态的治疗,包括:(a)预防哺乳动物出现疾病状态,特别是当这样的哺乳动物对疾病状态易感但尚未诊断患病时;(b)抑制疾病状态,即阻止其发展;和/或(c)缓解疾病状态,即使疾病状态消退。
[00308]“治疗有效量”打算包括当单独或联合给药时有效抑制XIa因子和/或血浆激肽释放酶的本发明化合物的量。“治疗有效量”还打算包括有效抑制XIa因子和/或血浆激肽释放酶的要求的化合物组合的量。化合物联合优选是协同的组合。当化合物联合给药的作用(在这时是抑制XIa因子和/或血浆激肽释放酶)大于各化合物以单一制剂单独给药的相加作用时发生协同作用,例如描述于Chou和Talalay,Adv.Enzyme Regul.1984,22:27-55的协同作用。通常,化合物在亚适浓度时协同作用表现最明显。协同作用可以表现为与各成分相比较时的低细胞毒性、增加的抗血栓形成和/或抗炎作用,或其它联合的有利作用。
[00313]本文引用的所有文献都通过引用全部结合到本文中。用于制备本发明化合物的起始原料的多种被取代的吡啶和吡啶酮化合物的合成方法已为本领域熟知,并已被广泛评论。(用于制备吡啶和吡啶酮起始原料的方法的实例见:Krohnke,F.Synthesis,1976,1.;Pyridineand Its Derivatives(吡啶及其衍生物)。The Chemistry of HeterocyclicCompounds(杂环化合物的化学),Abramovitch,R.A.,编辑;John Wiley和Sons:New York,1974;14卷;增刊1-4.;Comprehensive HeterocyclicChemistry(综合性杂环化学),2卷,Boulton,AJ.和McKillop,A,Eds.Pergamon Press,New York,1984,165-524页;ComprehensiveHeterocyclic Chemistry(综合性杂环化学),5卷,McKillop,A,Ed.Pergamon Press,New York,1996,1-300页)。用于制备本发明化合物的起始原料的多种被取代的嘧啶和嘧啶酮化合物的合成方法已为本领域所熟知,并已被广泛评论。(用于制备嘧啶和嘧啶酮化合物起始原料的方法的实例见:The Pyrimidines(嘧啶)。The Chemistry ofHeterocyclic Compounds(杂环化合物的化学),Taylor,E.C.,Ed.;JohnWiley和SonS:New York,1993;52卷)。
[00320]或者,可按方案5所示制备本发明的吡啶和吡啶酮化合物。可按方案4所述用β-酮基膦酸酯5a分两步制备化合物5c。用碳酸银和烷基碘化物(例如甲基碘)在溶剂(例如苯或氯仿)中可完成Rao描述的选择性O-烷基化(Rao,J.M,等,Tetrahedron,1989,45(22),7093及其中引用的文献),得到5d。或者,可用三氯氧化磷处理5c得到氯代吡啶5e。用NBS使5d/5e二溴化,然后在提高的温度下与吗啉反应,接着水解,得到醛5f和5g,可按方案1所述将其分别转化为5j和5k。通过Buchwald描述的改良方法(Buchwald,S.L.,TetrahedronLetters,1997,38(36),6363)将氯代化合物5k转化为胺5L。用HCl或BBr3使5h脱甲基后,根据O′Donnell描述的改良方法(O′Donnell,M.J.,PoIt,R.L.J.Org.Chem.,1982,47,2663),用二苯酮亚胺通过转亚氨基作用(transimination)将胺转化为亚胺。用碱(例如氢化钠)在溶剂(例如THF或DMF)中使吡啶酮去质子化,再用烷基卤化物(例如甲基碘)猝灭,得到N-烷基衍生物。用HCl水溶液将亚胺水解后,按方案1所述用合适的酰胺偶合剂使胺与羧酸1f偶合,得到5m。用有机合成领域技术人员已知的方法进一步处理A和R3上的官能基,将得到另外的本发明化合物。
[00321]用有机合成领域技术人员已知的方法处理R3上官能基的代表性实施例在方案6中显示。在正丁醇中将6a和6b/6c与肼一水合物一起加热分别得到3-氨基吲唑6d和3-羟基吲唑6e。根据Palermo描述的改良方法(Palermo,M.G.Tetrahedron Letters,1996,37(17),2885)使6a与醋羟胺酸和叔丁醇钾在DMF中反应得到3-氨基苯并异唑6f。或者,根据Lam描述的改良方法(Lam,P.Y.S.等,J.Med.Chem.2003,46,4405.),在DMA中加热6a和乙酸甲脒或乙酸乙脒,得到4-氨基喹唑啉6g和6h。类似地可根据Alexandre等所述(Tet.Lett.2002,43,3911),将对应的邻氨基苯甲酸衍生物6i与甲酰胺加热,制备喹唑啉酮6k。或者,可根据WO专利WO2005/012264公开的改良方法,将6j与乙酸铵和三甲基原甲酸酯一起加热,可制备喹唑啉酮6k。
[00328]用有机合成领域技术人员已知的方法处理R3上官能基的代表性实施例在方案12中显示。根据Queguiner描述的改良方法(Queguiher,G.等,Org.Chem.,1988,53,2740.),氟代吡啶12a可用胺(例如氢氧化铵)置换得到氨基吡啶12b,用醇盐例如(甲醇钠)置换得到12c,或用氢氧化钠置换得到12d。
[00329]当R3是嘧啶环系统时本发明的代表性实施例在方案13和14中显示。使脒13b(可用氰基吡啶13a通过Pinner反应合成)与适当取代的丙炔酯缩合可得到嘧啶酮13c。嘧啶酮13c可分两步转化为氨基嘧啶13d。区域异构的嘧啶合成如在方案14中描述。可根据Katritzky描述的改良方法(Katritzky,A.R.等,J.Org.Chem.,2003,68,4932),用酸14a制备β-酮腈(ketonitrile)14b。可根据Hirota的改良方法(Hirota,T.等,Synthesis,1991,303.),使14b与甲酰胺和氨缩合得到氨基嘧啶14c。β-酮腈14b还可用于合成吡唑(Watson,S.P.等,TetrahedronLetters,1997,38,9065.)
[00343]向固体2(35.5g)在CH2Cl2(500mL)中的冷却的(0°C)悬浮液中加入饱和NaHCO3(300mL)。将悬浮液剧烈搅拌使大部分固体溶解。分离各层并用CH2Cl2(200mL)提取水层。将合并的有机层用盐水洗涤,经MgSO4干燥,过滤并浓缩得到28g重的橙色液体。硅胶柱层析(CH2Cl2中的0-10%乙酸乙酯,然后用15∶1 CH2Cl2∶乙酸乙酯)得到13.0g 3A,为白色固体。按上述过程中和固体1,得到另外17.4g3A,为白色固体。合计获得30.4g(44%)3A。
[00354]7C.[(S)-2-苯基-1-(4-苯基-嘧啶-2-基)-乙基]-氨基甲酸叔丁酯:用微波辐射法使7A(57mg,0.15mmol)、7B(16mg,0.12mmol)和Na2CO3(31mg,0.30mmol)溶于乙腈并加热至120°C40分钟。将反应物冷却至室温并过滤。真空干燥滤液得到75mg(100%)7C,其无需进一步纯化即可用于下一步骤。MS 276.1(M+1)+。
[00358]8A:[(S)-1-(6-氧代-4-苯基-1,6-二氢-嘧啶-2-基)-2-苯基-乙基]-氨基甲酸叔丁酯:使7A(50mg,0.13mmol)、3-苯基丙酸乙酯(46mg,0.26mmol)和Hunig’s碱(34mg,0.26mmol)溶于EtOH(1mL)并加热至回流3天。将反应物冷却至室温,在真空中将溶剂蒸发干燥。使残留物再溶于含0.1%TFA的MeOH/H2O(9∶1)中,用制备HPLC离析,得到16mg需要的产物(31%产率)。MS 392.1(M+H)+。
[00359]8B.实施例8:用7D-F描述的方法将8A(16mg,0.041mmol)转化为实施例8,但用HOAt代替HOBt。
[00361]13A.4-氨甲基-环己烷羧酸{2-苯基-1-[4-(1-三异丙基硅烷基-1H-吡咯-3-基)-吡啶-2-基]-乙基}-酰胺,二(三氟乙酸盐):按照实施例3E描述的方法,用1-(三异丙基甲硅烷基)吡咯-3-硼酸代替3-(甲氧基羰基)苯基硼酸,得到13A(0.013g,16%),可用3D制备该化合物,为褐色残留物。MS 559.3(M+H)+。
[00385]在60°C加热环己基甲胺衍生物的联-TFA盐(0.028g,0.042mmol)和BBr3(1.0M在CH2Cl2中,0.42mL,0.42mmol)在CH2Cl2(1mL)中的溶液。2小时后,将反应物冷却至0°C,用MeOH猝灭,然后浓缩。制备HPLC(21.2×100mm,8分钟梯度,20至100%B,20mL/min.)得到实施例35(0.008g,35%),为粉红色固体。
[00390]37A.2-氯代-6-甲基-4-苯基吡啶:将6-甲基-4-苯基-1H-吡啶-2-酮(0.185g,1.0mmol)和POCl3(0.56mL,6mmol)在DMF(1mL)中的悬浮液加热至110°C。1.5小时后,将反应物冷却至室温,用水猝灭并用EtOAc提取。将合并的有机层用饱和NaHCO3、盐水洗涤,经Na2SO4干燥,过滤并浓缩。硅胶柱层析(0-10%EtOAc/己烷)得到37A(0.143g,70%),为黄色油状物。MS204.1(M+H)+和206.1(M+2+H)+。
[00393]37D.实施例37:将37C(0.045g,0.082mmol)、苯甲酮亚胺(0.028mL,0.16mmol)、Pd(OAc)2(0.0018g,0.0082mmol)、BINAP(0.0077g,0.012mmol)、Cs2CO3(0.064g,0.2mmol)和DMSO(0.55mL)加入可密封的试管内。用鼓泡氩气使混合物脱气10分钟,将试管密封,在85°C加热反应物。18小时后,将反应物冷却至室温,倾入水中并用CH2Cl2提取3次。将合并的有机层用盐水洗涤,经Na2SO4干燥,过滤并浓缩,得到苯甲酮亚胺衍生物(0.10g),为黄色油状物。
[00403]根据3E描述的方法,用3-羧基-4-氟代苯基硼酸代替3-(甲氧基羰基)苯基硼酸,用3D制备实施例52。
[00410]58A.6-[2-(1-氨基-2-苯基-乙基)-吡啶-4-基]-1H-喹啉-4-酮,三(三氟乙酸盐):在密封试管内将57(0.062g,0.074mmol)在浓HCl(0.5mL)和1,2-二氯乙烷(1.0mL)中的混合物加热至130°C。22小时后,浓缩反应物。制备HPLC(Phenomenex Luna 5u 21.2×100mm;8分钟梯度,20至100%B;20mL/min.)得到58A(0.031g,92%),为澄清无色油状物。MS 342.2(M+H)+。
[00411]58B.实施例58:向油状物的DMF(2mL)溶液中加入Boc-凝血酸(0.023g,0.089mmol)、BOP试剂(0.0393g,0.089mmol)和三乙胺(0.041mL,0.30mmol)。2小时后,加入水并用EtOAc提取反应物。将合并的有机层用盐水洗涤,经Na2SO4干燥,过滤并浓缩。制备HPLC(Phenomenex Luna 5u 21.2×100mm;8分钟梯度;30至100%B;20mL/min.)得到0.014g酰胺,为白色固体。使该固体溶于50%TFA的CH2Cl2(2mL)溶液。1小时后浓缩反应物。低压冻干后,制备HPLC(Phenomenex Luna 5u 21.2×100mm;8分钟梯度;20至100%B;25mL/min.)得到实施例58(0.010g,16%经过3步),为淡黄色固体。
[00412]实施例9、11-12、14、16-20、24、30-32、41-51、53和59-60的制备方法类似于上述方法。以下表1概括了本发明化合物的代表性实施例。
[00441]术语凝血酶抑制剂(或抗凝血酶剂)用于本文是指丝氨酸蛋白酶凝血酶的抑制剂。通过抑制凝血酶,可阻断多种凝血酶介导的过程,例如凝血酶介导的血小板激活(即例如血小板聚集和/或纤溶酶原激活物抑制剂-1和/或5-羟色胺的颗粒状分泌)、内皮细胞活化、炎性反应和/或纤维蛋白形成。本领域技术人员已知多种凝血酶抑制剂,可考虑将这些抑制剂与本发明化合物联合使用。这样的抑制剂包括但不限于硼精氨酸(boroarginine)衍生物、硼肽(boropeptides)、肝素、水蛭素和阿加曲班,包括其药学上可接受的盐和前体药物。硼精氨酸衍生物和硼肽包括硼酸的N-乙酰基和肽衍生物,例如赖氨酸、鸟氨酸、精氨酸、高精氨酸的C-端-氨基硼酸衍生物及其对应的异硫脲类似物。本文所用的术语水蛭素包括水蛭素的合适的衍生物或类似物,在本文称为hirulogs,例如二硫水蛭素。
[00453]适合与本发明化合物联合使用的减肥药的实例包括奥利司他和aP2抑制剂(例如在WO00/59506中公开的那些抑制剂)。
[00457]适合与本发明化合物联合使用的抗溃疡和胃食管反流疾病药的实例包括法莫替丁、雷尼替丁和奥美拉唑。
[00460]也可将本发明化合物用于涉及凝血酶、因子VIIa、IXa、Xa、XIa和/或血浆激肽释放酶的诊断性分析中。例如,可通过将有关的显色底物(例如XIa因子的底物S2366)加入一系列含测试样品和任选一种本发明化合物的溶液中,测定未知样品中凝血酶、因子VIIa、IXa、Xa、XIa和/和血浆激肽释放酶的存在。如果在含测试样品的溶液中检测到pNA产生,但在本发明化合物存在时检测不到,则可推断存在XIa因子。