Biphenyl 5,5'-bis-alkanoic acid derivatives, their production and use thereof

Abstract: A compound of formula (I): in which R is C₁₋₁₂ alkyl; lower alkyl wherein X₁ and X₂, which may be the same or different, are each hydrogen or a halogen; cyclohexylmethyl; cyclohexyl; tetrahydro-2H-pyran-1-yl-methyl; carboxy-lower alkyl or chloro-lower alkyl and each n, which may be the same or different, is 2 or 3, or a physiologically acceptable salt thereof.

Description: This invention relates to biphenyl derivatives, to a process for their preparation and to an aldose reductase inhibitor containing them. Among biphenyl derivatives having an aldose reductase inhibiting activity there are known aldostatin (as disclosed in JP-A-205095/1987) and FR 900280 (as disclosed in JP-A-72144/1990). These compounds are now under examination for their application to prevent or treat diabetic complications, such as cataracts, retinal disease, neuropathy and nephropathy. Nevertheless, there is still a demand for substances having a higher aldose reductase inhibiting activity than these. We have found biphenyl derivatives having a stronger aldose reductase inhibiting activity as compared with that of aldostatin. The present invention provides a compound of formula (I): in which R denotes C₁₋₁₂ alkyl; lower alkyl wherein X₁ and X₂, which may be the same or different, are each hydrogen or a halogen; cyclohexylmethyl; cyclohexyl; tetrahydro-2-H-pyran-1-yl methyl; carboxy-lower alkyl or chloro-lower alkyl and each n, which may be identical or different, is 2 or 3, or a physiologically acceptable salt thereof. The present invention also provides a process for preparing a compound of formula (I) or a physiologically acceptable salt thereof, which comprises hydrolysing a compound of formula (II): wherein R and n are as defined above and R₁ and R₂, which may be the same or different, are groups which are removable by hydrolysis, and, if desired, converting the compound of formula (I) thus obtained to a physiologically acceptable salt thereof. The present invention also provides an aldose reductase inhibitor which comprises a compound of formula (I) or a physiologically acceptable salt thereof and a carrier. The present invention further provides a compound of formula (I) or a physiologically acceptable salt thereof for use in a method of treatment of the human or animal body by therapy, especially for use in a method of treatment of a condition requiring an aldose reductase inhibitor. The present invention still further provides the use of a compound of formula (I) or a physiologically acceptable salt thereof in the manufacture of a medicament for the treatment of a condition requiring an aldose reductase inhibitor. The present invention additionally provides a process for producing an aldose reductase inhibitor which comprises mixing together a compound of formula (I) or a physiologically acceptable salt thereof and a carrier. By a "lower" group is meant a group having from 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms. Preferred R groups are benzyl, phenethyl, 2-fluoro-4-bromo-benzyl, cyclohexylmethyl, cyclohexyl, tetrahydro-2H-pyran-2-yl-methyl, C₁₋₁₂ alkyl such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, nonyl, decyl or undecyl, carboxy-lower alkyl such as carboxymethyl, 2-carboxyethyl, 3-carboxypropyl or 4-carboxypropyl, and chloro-lower alkyl such as chloromethyl, 2-chloroethyl, 3-chloropropyl or 4-chlorobutyl. Compounds of formula (I) can be produced in accordance with the following reaction scheme: in which R, R₁, R₂ and n are as defined above and X is a halogen atom, by alkylating the compound of general formula (III) with an alkyl halide of formula (V) to form the compound of formula (II) and then removing the ester group from the compound of formula (II) to form the free acid of formula (I). Examples of the alkyl halide of formula (V) are benzyl bromide, phenethyl bromide, 2-fluoro-4-bromo-benzyl bromide, cyclohexylmethyl bromide, cyclohexyl bromide, tetrahydro-2H-pyran-2-yl-methyl bromide, a C₁₋₁₂ alkyl bromide, a bromo-lower fatty acid ethyl ester or an ω-bromo-lower alkyl chloride. The alkylation can be realized in an organic solvent which will not participitate in the reaction, such as DMF, acetone, dioxane, tetrahydrofuran, benzene, toluene, xylene, ethyl acetate, methanol or ethanol, by introducing therein the esterified compound of formula (III) and the alkyl halide of formula (V) and conducting the reaction in the presence of an inorganic or organic base, for example, an alkali metal carbonate, such as anhydrous potassium carbonate or anhydrous sodium carbonate; an alkali metal hydroxide, such as sodium or potassium hydroxide; a tertiary alkylamine, such as trimethylamine or triethylamine; pyridine or a pyridine derivative, such as picoline, lutidine or 4-dimethylaminopyridine; a diazabicyclo compound, such as 1,5-diazabicyclo [4.3.0] -nonene-5, 1,4-diazabicyclo [2.2.2] -octane) or 1,8-diazabicyclo [5.4.0] - undecene-7; and a metal alkoxide, such as sodium methoxide or sodium ethoxide, together with, if necessary, a small amount of copper powder as a catalyst. The reaction is carried out in general at room temperature, or under heating to 50 - 100 °C for poorly reactive compounds, for a duration of 1 to 50 hours under stirring. The amounts of the reagents and catalyst are preferably from 1 to 20 moles of the halide, from 1.2 to 1.3 moles of the base and from 0.5 to 1.5 times by weight of the catalyst per mole of the starting compound. Among the starting compounds, namely, the esterified biphenyl compounds of formula (III), the compound in which n is 2 is known [Tetrahedron Letters, 52 ; 5211 (1978)] and the compound in which n is 3 (IIIb) can be prepared easily as shown in the following reaction scheme: by reacting pyridine-hydrochloric acid with a compound of formula (VI) at about 180°C to convert the alkoxy group into a hydroxy group and, then, esterifying the carboxyl groups of the resulting product of formula (VII) with, for example, a lower alcohol. The de-esterification reaction, namely hydrolysis of the ester groups the resulting compound of formula (II), can be effected by reacting the ester in an organic solvent, such as ethanol, methanol, dioxane, tetrahydrofuran or acetonitrile, with a base, such as sodium hydroxide or potassium hydroxide for 4 hours to 1 - 3 days at room temperature under stirring. The concentration of the base is in general from 1 to 3 N, and it is preferable to use it in an amount of about 2 - 10 moles, per mole of the compound of formula (II). The compound of formula (I) according to the present invention obtained as above can further be purified as desired using any known purifying means, such as column chromatography on silica gel or recrystallization. The compound of formula (I) can be converted into a corresponding physiologically acceptable salt with an inorganic cation, for example an alkali metal, such as sodium or potassium; an alkaline earth metal, such as calcium or magnesium; or ammonium or with an organic cation, for example a known organic amine. For preparaing an inorganic salt, the compound of formula (I) is preferably dissolved first in an aqueous solution containing at least an equivalent amount of hydroxide, carbonate or bicarbonate of a metal corresponding to the contemplated inorganic salt. A water-miscible organic solvent inert to the reaction, such as methanol, ethanol, acetone or dioxane, may be admixed with the reaction mixture. If sodium hydroxide, sodium carbonate or sodium bicarbonate is employed, a solution of the corresponding sodium salt will be obtained. A solid salt can be obtained by evaporating off the solvent of such a solution or by adding to the solution a water-soluble organic solvent having some polarity, such as butanol or ethyl methyl ketone, to cause precipitation of the solid salt. The compound of formula (I) or the salt thereof can be prescribed as an aldose reductase inhibitor as such or in the form of a preparation with a known carrier. The aldose reductase inhibitor of the present invention can be administered to a patient or to an experimental animal, for example orally, rectally or parenterally, such as by intraveous, intramuscular, subcutaneous, intraperitoneal or ophthalmic administration. The preparation of the compound of the present invention may be formulated so as to adapt to each of the above administration means. The preparation may be in a form such as a pellet, pill, powder, granule, capsule, suppository, injection, preparation or eye lotion. For formulating such preparations for oral administration, such as a tablet, granule or encapsulated drug, the compound of the present invention may be mixed with an excipient such as a carrier, for example fillers such as starch lactose, sucrose, mannite, carboxymethyl cellulose, corn starch and various inorganic salts; a binder such as starch, dextrin, gum arabic, gelatine, hydroxypropyl starch, methyl cellulose, sodium carboxymethyl cellulose, hydroxypropyl cellulose, crystalline cellulose, ethyl cellulose, polyvinyl pyrrolidone and macrogol; a disintegrator such as starch, hydroxypropyl starch, carboxymethyl cellulose, sodium carboxymethyl cellulose and hydroxypropyl cellulose; a surface active agent such as sodium lauryl sulfate, soy bean lecithin, a fatty acid ester of sucrose and polysorbate 80 ; a lubricating agent such as talc, wax, a hydrogenated vegetable oil, a fatty acid ester of sucrose, magnesium stearate and calcium stearate; a fluidizability promotor; a taste modifier; a colouring agent and a flavour. The compound of formula (I) or a salt thereof can be administered in a form of suspension, emulsion, syrup or elixir. For parenteral preparations, there may be incorporated in, in general, distilled water for injection, physiological saline solution, an aqueous glucose solution, vegetable oils for injection, propylene glycol or polyethylene glycol as the diluent. It is permissible to further incorporate as desired a sterilizer, an antiseptic or a stabilizer. It is possible to process such parenteral preparations in consideration of their feeble stability into a freeze-dried product by, after filling in a suitable vessel such as glass vial, freeze drying. The preparation is then diluted with a diluent directly before use. It is also possible, for example to incorporate into the preparation as desired an tonicity agent, a stabilizer, an aspectic or an analgesic. The administration dose of the compound of formula (I) or the salt thereof may vary in accordance with each selected administration route and with the condition of the recipient such as age, body weight and disease condition. In general the dose is 5 milligram to 1 gram preferably about 25 milligram to about 300 milligram, calculated as the compound of formula (I), per day per man once a day or up to three times a day. Various compounds of formula (I) according to the present invention have been examined for their pharmacodynamic behavior and for their acute toxicity, of which the results are given below. 1) METHOD FOR DETERMINING THE INHIBITORY ACTIVITY ON ENZYME REACTION The preparation of the aldose reductase and the determination of the inhibition on enzyme reaction activity were carried out pursuant to the procedures disclosed by Haymann et al in Journal of Biological Chemistry 240, 877 (1965). The sample solution to be examined for inhibitory activity was prepared by dissolving the compound of formula (I) in a small amount of methanol and supplementing the resulting methanol solution by diluting with distilled water up to a tenfold volume. A partially purified bovine lens aldose reductase was used for an assay. To 2.4 ml solution of 5 × 10⁻⁵ M NADPH dissolved in a 2/15 M phosphate buffer solution (pH = 6.0), 0.4 ml of the enzyme solution (15 m units/ml) and 0.1 ml of the sample solution to be examined were added and the mixture in a quartz cell in a photoelectric photometer was subjected to pre-incubation at 37°C for 4 minutes. Then, 0.1 ml of a 0.015 M D, L-glyceraldehyde solution was added thereto to initiate the enzyme reaction and the decrease in the optical absorption at 340 nm was measured at 37°C for 4 minutes. The inhibitory activity on aldose reductase was calculated by the following equation : in which A represents the enzyme reaction rate with addition of the inhibitor and B denotes the enzyme reaction rate without addition of the inhibitor. 2) ACTIVITY FOR SUPPRESSING ACCUMULATION OF SORBITOL (A) Tissue Culture Lenses and sciatic nerves extirpated from Wistar rats male, aged 7 weeks, were washed twice with an aseptic buffer solution consisting of 0.3 % trisaminomethane, 0.8 % NaCl, 0.038 % KCl, 0.025 % Na₂HPO₄ · 12H₂O, 0.1 % glucose and 1.85 ml/l of concentrated HCl. The lenses and the sciatic nerves were then pre-incubated for 30 minutes in a culture medium prepared by adding 2 ml of 7.5 % NaHCO₃ aseptic solution and 5.5 ml of aseptic calf fetus serum to 100 ml of an aseptic culture medium of 0.98 % TC Medium 199 (NISSUI corp.) containing 0.01 % of dihydrostreptomycin and 0.01 % of benzylpenicillin. Thereafter, the intrinsic culture was effected in a culture medium prepared by adding each sample solution to be examined and 0.9 % of glucose to the above mentioned culture medium for 20 hours. The incubation was effected at 37°C in an atmosphere composed of 95 % air and 5 % CO₂. After the culture, the cultured samples of lens and sciatic nerve were taken out of the culture medium on to a filter paper and the weight of each of them was measured after the adherent culture solution had been swept off. Then, each of the cultured samples was homogenized with addition of 1 ml of a cold 8 % HClO₄ solution and the homogenized mixture was subjected to centrifugation at 10,000 G for 10 minutes, whereby a supernatant was obtained. The resulting precipitate was then homogenized again with addition thereto of 0.5 ml of a cold 8 % HClO₄ solution and the homogenized mixture was again subjected to a centrifugation in a similar way as above to obtain a further supernatant. This was put together with the previously obtained supernatant, the resulting solution was neutralized with 2 N KOHaq. solution and was supplemented with distilled water to a volume of 5 ml. The precipitate formed by the neutralization was separated by centrifugation at 3,000 rpm for 10 minutes and the resulting supernatant was employed as the sample for determining the sorbitol content. (B) Determination of Sorbitol Content The determination of the sorbitol content in the lens and in the sciatic nerve was carried out in accordance with the method disclosed by Bergmeyer in " Methods of Enzymatic Analysis " edited by H. U. Bergmeyer, pp 1323 - 1326, Academic Press, New York, 1974 and in accordance with the method by Malaon et al in " Diabetes " 29 , 861 - 864 (1980). To 0.5 ml of the sample solution for examining for the sorbitol content obtained as above, 0.9 ml of 0.1 M glycine -KOH buffer solution (pH 9.4) containing 1 mM of NAD* and 0.1 ml of a solution of sorbitol dehydrogenase of 20 Units/ml were added and the resulting mixture was subjected to incubation at 37 °C for 1 hour. The content of sorbitol in each tissue was estimated by assuming the increment of the optical absorption at 340 nm to be proportional to the amount of NADH produced by the reaction, for the lens and by detecting the fluorescence at an excitation wavelength of 366 nm and a fluorescence wavelength of 425 nm for the sciatic nerve. The activity for suppressing accumulation of sorbitol, or the aldose reductase inhibiting activity, was calculated from the determined sorbitol content by the formula: in which A denotes the content of sorbitol per unit weight of the tissue after cultivation with addition of the inhibitor, B denotes the sorbitol content per unit weight of the tissue after cultivation without addition of the inhibitor and C represents the sorbitol content per unit weight of the tissue after cultivation in the medium without addition of glucose and inhibitor. The results of the tests according to 1) and 2) are summarized in Table 1 below. The diester intermediate of formula (II) in the production of the compound of formula (I), for example the compounds obtained in Reference Examples 1 - 17 and 21 - 31, did not exhibit any aldose reductase inhibiting activity and any activity for suppressing accumulation of sorbitol. 3) ACUTE TOXICITY A compound of formula (I), for example those given in Examples 1 - 28 below, was suspended in distilled water and was dissolved completely by adding at least an equimolar amount of aqueous NaOH solution. The pH of the resulting solution was adjusted to 6.5 - 7.0 and the solution was administered to STD-DDY mice, aged 5-weeks, 3 mice in a group, orally, 400 mg/20 ml/kg and each group was observed for 10 days. No death was observed in any of the administered groups. As is clear from the experimental results, the compounds of the present invention exhibit a superior inhibitory activity on aldose redusctase and excellent stability, so that they can be used advantageously as aldose reductase inhibitors for the prevention or therapy of, for example cataracts, retinal diseases, noirosis, nephropathy, corneal disorders and diabetic uveitis. The present invention will now be further described in more detail in the following Examples and Reference Examples. Reference Example 1 Synthesis of 2- benzyloxy-2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 1 ml of a DMF solution containing 55.5mg (0.1438 mmol) of 2,2'-dihydroxy-5,5'-bis(2-ethoxycarbonylethyl)biphenyl and 21.82 µl (0.1798 mmol) of benzyl iodide, there were added 27.43 µl (0.1798 mmol) of DBU and the resulting mixture was agitated for 4.5 hours at room temperature. After the solvent in the reaction mixture was evaporated of under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 5 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/1) to obtain 52.8 mg (0.111 mmol, 77 %) of 2-benzyloxy-2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.23 (6H, t, 2CH₃), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.13 (4H, q, 2CH₂), 5.06 (2H, s, CH₂), 6.27 (1H, s, OH), 6.8-7.4 (11H, m, arom-H) MS (FAB) : 475 (M-H)⁻ Reference Example 2 Synthesis of (2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2,2'-dihydroxy-5,5'-bis(2-ethoxycarbonylethyl)biphenyl and 716.7 µl (5.181 mmol) of 2-fluoro-4-bromobenzylbromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 1 hour at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduce pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, water and aqueous sodium biacarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 50 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/1 and 50/1) to obtain 212.4 mg (0.3706 mmol, 72 %) of 2-(2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.23 (6H, t, 2CH₃), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.13 (4H, q, 2CH₂), 5.05 (2H, s, CH₂), 5.95 (1H, s, OH), 6.8-7.3 (9H, m, arom-H) MS (FAB) : 571 (M-H)⁻ Reference Example 3 Synthesis of 2- cyclohexylmethoxy-2'- hydroxy5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 3 ml of a DMF solution containing 100 mg (0.259 mmol) of 2,2'-dihydroxy-5,5'-bis(2-ethoxycarbonylethyl) biphenyl and 365.2 µl (2.591 mmol) of cyclohexylmethyl bromide, there were added 42.9 mg (0.3109 mmol) of anhydrous potassium: carbonate and a small amount of copper powder and the resulting mixture was agitated for 36 hours at room temperature. After 22 hours from the start of the reaction, 365.2 µl (2.591 mmol) of cyclohexymethyl bromide was further added there to. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filterate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and sodium chloride aqueous solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 10 g of WAKO-gel C-200, eluent: hexane and toluene/ethyl acetate of 100/l and 25/1) to obtain 105.2 mg (0.2486 mmol, 84 %) of 2-cyclohexylmethoxy-2'-bis (2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm): 0.8-2.0 (11H, m, cyclohexyl-H), 1.23 (6H, t, 2CH₃), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 3.81 (2H, d, CH₂), 4.13 (4H, q, 2CH₂), 6.50 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 481 (M-H)⁻ Reference Example 4 Synthesis of 2-(tetrahydro-2H-pyran-2-yl)methoxy-2'-hydroxy-5,5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2,2'-dihydroxy-5,5'-bis(2-ethoxycarbonylethyl)biphenyl and 678 µl (5.181 mmol) of 2-bromomethyl-tetrahydro-2H-pyran, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 1 hour at 100 °C. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filterate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 10 g of WAKO-gel C-200, eluent: hexane and toluene/ethyl acetate of 100/l and 50/1 and 30/l) to obtain 134.5 mg (0.2779 mmol, 54 %) of 2-(tetrahydro-2H-pyran-2-yl)methoxy-2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm): 1.1-2.0 6H, m, 3CH₂), 1.24 (6H, t, 2CH₃), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 3.2-3.8 (2H, m, CH₂), 3.8-4.3 (7H, m, 3CH₂, CH), 6.72 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 483 (M-H)⁻ Reference Example 5 Synthesis of 2- propoxy-2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2,2'-dihydroxy-5,5'-bis(2-ethoxycarbonylethyl)biphenyl and 475.4 µl (5.181 mmol) of propyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 17 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 10 g of WAKO-gel C-200, eluent: hexane and toluene/ethyl acetate of 100/l and 50/1) to obtain 188.3 mg (0.4399 mmol,85 %) of 2- propoxy-2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl)biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.93 (3H, t, CH₃), 1.23 (6H, t, 2CH₃) , 1.5-2.0 (2H, m, CH₂), 2.5-2.8 (4H , m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 3.98 (2H, t, CH₂), 4.13 (4H, q, 2CH₂) , 6.57 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 427 (M-H)⁻ Reference Example 6 Synthesis of 2- butoxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 3 ml of a DMF solution containing 100 mg (0.2591 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 281.1 µl (2.591 mmol) of butyl bromide, there were added 42.9 mg (0.3109 mmol) of anhydrous pottasium carbonate and a small amount of copper powder and the resulting mixture was agitated for 23 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 10 g of WAKO-gel C-200, eluent: hexane and tolene/ethyl acetate of 100/l and 50/1) to obtain 99.6 mg (0.2253 mmol, 87 %) of 2- butoxy-2'- hydroxy-5, 5'-bis(2-ethoxycarbonylethyl)biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.88 (3H, t, CH₃), 1.23 (6H, t, 2CH₃) , 1.20-2.0 (4H, m, 2CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂) , 4.02 (2H, t, CH₂), 4.13 (4H, q, 2CH₂), 6.56 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB): 441 (M-H)⁻ Reference Example 7 Synthesis of 2- pentyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 100 mg (0.2591 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 331.3 µl (2.591 mmol) of pentyl bromide, there were added 42.9 mg (0.3109 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 7 g of WAKO-gel C-200, eluent: hexane and toluene/ethyl acetate of 50/1) to obtain 97.2 mg (0.2131 mmol, 82 %) of 2-pentyloxy-2'- hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.85 (3H, t, CH₃), 1.23 (6H, t, 2CH₃) , 1.1-1.5 (4H, m, 2CH₂), 1.6-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.01 (2H, t, CH₂), 4.13 (4H, q, 2CH₂), 6.57 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 455 (M-H)⁻ Reference Example 8 Synthesis of 2- hexyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 4 ml of a DMF solution containing 97 mg (0.2513 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 363.7 µl (2.513 mmol) of hexyl bromide, there were added 41.6 mg (0.3109 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 10 g of WAKO-gel C-200, eluent: hexane and toluene/ethyl acetate of 100/1) to obtain 94.4 mg (0.2008 mmol, 80 %) of 2-hexyloxy -2'- hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.83 (3H, t, CH₃), 1.23 (6H, t, 2CH₃) , 1.1-1.5 (6H, m, 3CH₂), 1.6-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.01 (2H, t, CH₂), 4.13 (4H, q, 2CH₂), 6.57 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 469 (M-H)⁻ Reference Example 9 Synthesis of 2- heptyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 4 ml of a DMF solution containing 94 mg (0.2435 mmol) of 2, 2'-dihydroxy-5, 5'bis(2-ethoxycarbonylethyl) biphenyl and 394.4 µl (2.435 mmol) of heptyl bromide, there were added 40.3 mg (0.3109 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 10 g of WAKO-gel C-200, eluent: benzene and benzene/ethyl acetate of 300/l, 150/l and 50/1) to obtain 88.1 mg (0.182 mmol, 75 %) of 2-heptyloxy -2'- hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.85 (3H, t, CH₃), 1.23 (6H, t, 2CH₃) , 1.1-1.5 (8H, m, 4CH₂), 1.6-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.01(2H, t, CH₂), 4.13 (4H, q, 2CH₂), 6.58 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 483 (M-H)⁻ Reference Example 10 Synthesis of 2- octyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 913.3 µl (5.181 mmol) of octyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l and 50/1) to obtain 230.4 mg (0.627 mmol, 89 %) of 2-octyloxy -2'- hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.87 (3H, t, CH₃), 1.24 (6H, t, 2CH₃) , 1-1-1.5 (10H, m, 5CH₂), 1.5-1-9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.01 (2H, t, CH₂), 4.14 (4H, q, 2CH₂), 6.58 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 497 (M-H)⁻ Reference Example 11 Synthesis of 2- undecyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5,-bis(2-ethoxycarbonylethyl) biphenyl and 1179.8 µl (5.181 mmol) of undecyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l) to obtain 245.5 mg (0.456 mmol, 88 %) of 2-undecyloxy-2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.88 (3H, t, CH₃), 1.1-1.5 (22H, m, 8CH₂, 2CH₃), 1.6-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H , m, 2CH₂), 4.01 (2H, t, CH₂), 4.13 (4H, q, 2CH₂), 6.58 (1H, s, OH), 6.8 -7.3 (6H, m, arom-H) MS (FAB) : 539 (M-H)⁻ Reference Example 12 Synthesis of 2- isopentyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 646.5µl (5.181 mmol) of isopentyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l and 50/l) to obtain 208.2 mg (0.456 mmol, 88 %) of 2-isopentyloxy-2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.86 (6H, d, 2CH₃), 1.24 (6H, t, 2CH₃), 1.5-1.8 (3H, m, CH₂, CH), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H , m, 2CH₂), 4.04 (2H, t, CH₂), 4.13 (4H, q, 2CH₂), 6.55 (1H, s, OH), 6.8 -7.3 (6H, m, arom-H) MS (FAB) : 455 (M-H)⁻ Reference Example 13 Synthesis of 2-(3-ethoxycarbonylpropoxy)- 2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 780.5 µl (5.181 mmol) of 4-bromobutylic acid ethyl ester, there were added 85.8 mg (0.6217 mmol)of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/l 30/l, 20/l, 10/l, 9/l,and 8/l) to obtain 100.7 mg (0.2014 mmol, 39 %) of 2-(3-ethoxycarbonylpropoxy) -2'- hydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.22 (3H, t, CH₃), 1.23 (6H, t, 2CH₃) , 1.8-2.2 (2H, m, CH₂), 2.2-2.5 (2H , m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 3.9-4.3 (8H , m, 4CH₂), 6.24 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 499 (M-H)⁻ Reference Example 14 Synthesis of 2- phenethyloxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 707.6 µl (5.181 mmol) of phenethyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l and 50/l) to obtain 218.1 mg (0.4451mmol, 86 %) of 2-phenethyloxy -2'- hydroxy- 5, 5'- bis (2-ethoxy-carbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.23 (6H, t, 2CH₃), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (6H, m, 3CH₂), 4.12 (2H, q, CH₂), 4.13 (2H, q, CH₂), 4.2 0 (2H, t, CH₂), 6.20 (1H, s, OH), 6.8 -7.3 (11H, m, arom-H) MS (FAB) : 489 (M-H)⁻ Reference Example 15 Synthesis of 2- cyclohexyloxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis(2-ethoxycarbonylethyl) biphenyl and 644.5 µl (5.181 mmol) of cyclohexyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 41 hours at room temperature, for a further 5 hours at 70 °C and for 8 hours at 100 °C. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 1000/l and 500/l) and further purified by silica-gel column chromatography (with 15 g of WAKO-gel C-200, eluent: hexane and hexane/ethyl acetate 50/l, 30/l. 15/l and 12/l) to obtain 28.3 mg (0.0605 mmol, 12 %) of 2- cyclohexyloxy- 2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.23 (6H, t, 2CH₃), 1.0-2.0 (10H, m, cyclohexyl-5CH₂), 2.5-2.8 (4H, m, 2CH₂) , 2.8-3.1 (4H, m, 2CH₂), 4.13 (4H, q, 2CH₂), 4.0-4.6 (1H, m, cyclohexyl-CH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 467 (M-H)⁻ Example 1 Synthesis of 2- benzyloxy-2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 0.5 ml of an ethanol solution containing 110 mg (0.2311 mmol) of 2-benzyloxy-2'hydroxy-5,5'-bis (2-ethoxycarbonylethyl)biphenyl obtained in Reference Example 1, 762.4 µl (0.7626 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at 4 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 73 mg (0.1738 mmol, 75 %) of 2-benzyloxy-2'-hydroxy-5, 5'-bis (2-carboxylethyl) biphenyl as an oily product was obtained. ¹H-NMR (CDCl₃) δ (ppm) : 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H , m, 2CH₂), 5.10 (2H, s, CH₂), 6.8-7.3 (11H, m, arom-H) MS (FAB) : 419 (M-H)⁻ Example 2 Synthesis of 2-(2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 5.1 ml of an ethanol solution containing 182.5 mg (0.3186 mmol) of 2- (2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5,5'-bis (2-ethoxycarbonylethyl)biphenyl obtained in Reference Example 2, 1.27 ml (1.27 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 50 hours. After 40 hours from starting the reaction, 1.27 ml (1.27 mmol) of 1 N-sodium hydroxide solution was further added there to and stirred at room temperature for 50 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, am amount of water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 150.5 mg (0.2912 mmol, 91 %) of 2-(2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5, 5'-bis(2-carboxyethyl)biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H , m, 2CH₂), 5.00 (2H, s, CH₂), 6.8-7.3 (9H, m, arom-H) MS (FAB) : 515 (M-H)⁻ Example 3 Synthesis of 2- cyclohexylmethoxy-2'-hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 3.1 ml of an ethanol solution containing 93.3 mg (0.1936 mmol) of 2- cyclohexylmethoxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 3, 0.744 ml (0.744 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 50 hours. After 40 hours from starting the reaction, 0.744 ml (0.744 mmol) of 1 N sodium hydroxide solution was further added thererto. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 72.8 mg (0.1709 mmol, 88 %) of 2-cyclohexylmethoxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl as an oily product was obtained. ¹H-NMR (MeOH-d₄) δ (ppm) : 0.6-2.0 (11H, m, cyclohexyl-H), 2.4-2. 7 (4H, m, 2CH₂), 2.7-3.0 (4H, m, 2CH₂), 3.73 (2H, d, 2CH₂), 6.7-7.2 (6H, m, arom-H) MS (FAB): 425 (M-H)⁻ Example 4 Synthesis of 2-(tetrahydro-2H-pyran-2-yl) methoxy-2'-hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 3.67 ml of an ethanol solution containing 91.8 mg (0.1836 mmol) of 2-(tetrahydro-2H-pyran-2-yl)methoxy-2'-hydroxy- 5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 4, 0.734 ml (0.734 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 28 hours. After 18 hours from starting the reaction, 0.734 ml (0.734 mmol) of 1N sodium hydroxide solution was further added thererto. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 76.3 mg (0.1783 mmol, 97 %) of 2-(tetrahydro-2H-yl) methoxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl)biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.1-2.0 (6H, m, 3CH₂), 2.5-2.8 (4H , m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 3.2-3.8 (2H, m, CH₂), 3.9-4.2 (3H, m, CH₂, CH), 6.7-7.3 (6H, m, arom-H) MS (FAB) : 427 (M-H)⁻ Example 5 Synthesis of 2- propoxy-2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 2.79 ml of an ethanol solution containing 149.5 mg (0.3493 mmol) of 2- propoxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 5, 2.79 ml (2.79 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 22 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 124.7 mg (0.3352 mmol, 96 %) of 2-propoxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl)biphenyl were obtained as an oily product. ¹H-NMR (CDCL₃) δ (ppm) : 0.94 (3H, t, CH₃), 1.76 (2H, m, CH₂) , 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.00 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 371 (M-H)⁻ Example 6 Synthesis of 2- butoxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 3.1 ml of an ethanol solution containing 84.5 mg (0.1912 mmol) of 2- butoxy -2'- hydroxy- 5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 6, 0.765 ml (0.765 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 50 hours. After 40 hours from starting the reaction, 0.765 ml (0.765 mmol) of 1 N sodium hydroxide solution was further added thereto. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 70.1 mg (0.1816 mmol, 95 %) of 2-butoxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl)biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.89 (3H, t, CH₃), 1.2-1.9 (4H, m, 2CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.05 (2H, t, CH₂) , 6.8-7.3 (6H, m, arom-H) MS (FAB) : 385 (M-H)⁻ Example 7 Synthesis of 2- pentyloxy -2'- hydroxy-5, 5,-bis (2-carboxyethyl) biphenyl To 1.16 ml of an ethanol solution containing 88.2 mg (0.1934 mmol) of 2- pentyloxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 7, 0.580 ml (0.580 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 10.5 hours. After 5.5 hours from starting the reaction, 0.1934 ml (0.1934 mmol) of 1 N sodium hydroxide solution and methanol (1.16 ml) were further added thereto, then the mixture was stirred for 2 hours and further for 3 hours at 60°C. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 71 mg (0.1775 mmol, 92 %) of 2- pentyloxy-2'-hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.85 (3H, t, CH₃), 1.2-1.5 (4H, m, 2CH₂), 1.5-1.9 (2H, m, 2CH₂), 2.5 - 2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.03 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 399 (M-H)⁻ Example 8 Synthesis of 2- hexyloxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 1.01 ml of an ethanol solution containing 79.2 mg (0.1685 mmol) of 2- hexyloxy -2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 8, 0.506 ml (0.506 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 20 hours. After 5.5 hours from starting the reaction, 0.168 ml (0.168 mmol) of 1 N sodium hydroxide solution and methanol (1.01 ml) were further added thereto and stirred for 14.5 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 67.6 mg (0.1633 mmol, 97 %) of 2- hexyloxy -2'- hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.84 (3H, t, CH₃), 1.1-1.5 (6H, m, 3CH₂), 1.5-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.04 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB): 413 (M-H)⁻ Example 9 Synthesis of 2- heptyloxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 2.5 ml of a methanol solution containing 74.3 mg (0.1535 mmol) of 2 -heptyloxy-2'-hydroxy-5,5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 9, 0.614 ml (0.614 mmol) of 1 N sodium hydroxide were added and the mixture was agitated at room temperature for 54 hours. After 44 hours from starting the reaction, 0.614 ml (0.614 mmol) of 1 N sodium hydroxide solution was further added thereto and stirred for 10 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 63.2 mg(0.1477 mmol, 96 %) of 2-heptyloxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.85 (3H, t, CH₃,), 1.1-1.5 (8H, m, 4CH₂), 1.5-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.04 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB): 427 (M-H)⁻ Example 10 Synthesis of 2- octyloxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 3.17 ml of a methanol solution containing 197.1 mg (0.3597 mmol) of 2-octyloxy -2'- hydroxy- 5,5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 10, 3.17 ml (3.17 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 22.5 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 173.2 mg (0.3917 mmol, 99 %) of 2-octyloxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.86 (3H, t, CH₃), 1.1-1.5 (10H, m, 5CH₂), 1.5-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.03 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB): 441 (M-H)⁻ Example 11 Synthesis of 2- undecyloxy -2'-hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 3.24 ml of an ethanol solution containing 218.6 mg (0.4048 mmol) of 2-undecyloxy -2'-hydroxy- 5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 19, 3.24 ml (3.24 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 22.5 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 191.9 mg (0.3965 mmol, 98 %) of 2-undeloxy-2'-hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.88 (3H, t, CH₃), 1.1-1.5 (16H, m, 8CH₂), 1.5-1.9 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.04 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 483 (M-H)⁻ Example 12 Synthesis of 2-isopentyloxy-2'-hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 3.09 ml of an ethanol solution containing 176.1 mg (0.3862 mmol) of 2-isopentyoxy-2'-hydroxy-5,5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 12, 3.09 ml (3.09 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 22.5 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 153.1 mg (0.3828 mmol, 99 %) of 2 -isopentyloxy -2'-hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.88 (6H, d, (CH₃)₂), 1.6-1.9 (3H, m, CH₂, CH), 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.06 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 399 (M-H)⁻ Example 13 Synthesis of 2-(3-carboxypropoxy)-2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 6.9 ml of an ethanol solution containing 86.3 mg (0.1726 mmol) of 2-(3-ethoxycarbonylpropoxy)-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 13, 1.38 ml (1.38 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 63 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 67.7 mg (0.1627 mmol, 94 %) of 2-(3-carboxypropoxy)-2'-hydroxy-5, 5'-bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (MeOH-d₄) δ (ppm) : 1.8-2.1 (2H, m, CH₂), 2.2-2.5 (2H, m, CH₂), 2.5-2.8 (4H, m, 2CH₂), 2.8 -3.1 (4H, m, 2CH₂), 3.97 (2H, t, CH₂) , 6.7-7.2 (6H, m, arom-H) MS (FAB) : 415 (M-H)⁻ Example 14 Synthesis of 2- phenethyloxy -2'- hydroxy-5, 5' bis (2-carboxyethyl) biphenyl To 12.2 ml of an ethanol solution containing 186.6 mg (0.3808 mmol) of 2-phenetyloxy-2'-hydroxy-5,5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 14, 3.05 ml (3.05 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 22 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 158.7 mg (0.3656 mmol, 96 %) of 2- phenethyloxy -2'-hydroxy-5, 5'- bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 2.5-2.8 (4H, m, 2CH₂), 2.8-3.1 (6H , m, 3CH₂), 4.22 (2H, t, CH₂), 6.8-7.3 (11H, m, arom-H) MS (FAB) : 433 (M-H)⁻ Example 15 Synthesis of 2- cyclohexyloxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 1.32 ml of an ethanol solution containing 24.6 mg (0.0526 mmol) of 2 -cyclohexyloxy -2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 15, 0.263 ml (0.263 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 47 hours. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 21.6 mg (0.0524 mmol, 99 %) of 2 -cyclohexyloxy-2'-hydroxy-5, 5'- bis(2-carboxyethyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.0-2.0 (10H, m, cyclohexyl-5CH₂), 2.5 -2.8 (4H, m, 2CH₂), 2.8-3.1 (4H, m, 2CH₂), 4.0-4.4 (1H, m, cyclohexyl-CH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 411 (M-H)⁻ Reference Example 16 Synthesis of 2- methoxy-2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5,5'-bis(2-ethoxycarbonylethyl) biphenyl and 0.3292 ml (5.181 mmol) of methyl iodide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 2 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 25/l) to obtain 188.9 mg (0.4723 mmol, 91 %) of 2-methoxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl)biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.24 (6H, t, 2CH₃), 2.62 (4H, t, 2CH₂), 2.9-3.0 (4H, m, 2CH₂), 3.87 (3H, s, CH₃), 4.13 (4H, q, 2CH₂), 6.13 (1H, s, OH), 6.9-7.3 (6H, m, arom-H) MS (FAB) : 400 (M)⁺ Reference Example 17 Synthesis of 2- ethoxy-2'- hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy -5,5'-bis(2-ethoxycarbonylethyl) biphenyl and 0.423 ml (5.181 mmol) of ethyl iodide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200 eluent: toluene and toluene/ethyl acetate of 100/l and 75/l) to obtain 141.6 mg (0.3420 mmol, 66 %) of 2- ethoxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl)biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.24 (6H, t, 2CH₃), 1.36 (3H, t, CH₃) , 2.62 (2H, t, CH₂), 2.63 (2H, t, CH₂) , 2.94 (2H, t, CH₂), 2.95 (2H, t, CH₂) 4.11 (2H, q, CH₂), 4.13 (4H, q, 2CH₂) , 6.66 (1H, s, OH), 6.9-7.3 (6H, m, arom-H) MS (FAB) : 414 (M⁺) Example 16 Synthesis of 2- methoxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 10 ml of an ethanol solution containing 160.9 mg (0.4023 mmol) of 2 -methoxy -2'-hydroxy-5, 5'-bis(2-ethoxycarbonylethyl)biphenyl obtained in Reference Example 16, 3.22 ml (3.218 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature overnight. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was acidified using 1 N hydrochloric acid to a pH of about 1 - 2. The thereby formed precipitate was filtered, washed with water and then dried. The 135.6 mg (0.3942 mmol, 98 %) of 2-methoxy-2'-hydroxy-5, 5,- bis(2-carboxyethyl) biphenyl were obtained as a white solid. ¹H-NMR (CDCl₃) δ (ppm) : 2.6-2.7 (4H, m, 2CH₂), 2.9-3.0 (4H , m, 2CH₂), 3.90 (3H, s, CH₃), 6.9-7.3 (6H, m, arom-H) MS (FAB) : 344 (M⁺) Example 17 Synthesis of 2- ethoxy -2'- hydroxy-5, 5'-bis (2-carboxyethyl) biphenyl To 8 ml of an ethanol solution containing 139.3 mg (0.3365 mmol) of 2 - ethoxy - 2'-hydroxy-5, 5'-bis (2-ethoxycarbonylethyl) biphenyl obtained in Reference Example 17, 2.69 ml (2.692 mmol) of 1 N sodium hydroxide solution were and the mixture was agitated at room temperature overnight. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was acidified using 1 N hydrochloric acid to a pH of about 1 - 2. The thereby formed precipitate was filtered washed with water and then dried to obtain 95.1 mg (0.2656 mmol, 79 %) of 2-ethoxy-2'-hydroxy- 5, 5'-bis (2-carboxyethyl)biphenyl as a white solid product. ¹H-NMR (CDCl₃) δ (ppm) : 1.38 (3H, t, CH₃), 2.6-2.7 (4H, m, 2CH₂), 2.9-3.0 (4H, m, 2CH₂), 4.13 (2H, q, CH₂), 6.9-7.3 (6H, m, arom -H) MS (FAB) : 358 (M⁺) Reference Example 18 Synthesis of 2, 2'- dihydroxy-5, 5'-bis (3-carboxypropyl) biphenyl A mixture of pyridine (30 ml) and conc. hydrochloric acid (30 ml) was heated at about 180 °C for 30 minutes. A known compound, 2, 2'-dimethoxy -5, 5'-bis (3-carboxypropyl) biphenyl (1.2 g) was added thereto and heated at about 180 °C with stirring overnight. Upon cooling, the reaction mixture was poured into ice-water and the mixture was extracted with ethyl acetate under acidic condition with hydrochloric acid. The ethyl acetate layer was washed with aqueous saturated sodium chloride, dried by adding anhydrous magnesium sulfate, then the solvent was evaporated off under reduced pressure. The residue was re-precipitated by adding ethyl acetate-toluene to obtain 2, 2'-dihydroxy-5, 5'-bis (3-carboxypropyl) biphenyl (1.01 g, 91 %) as a white powder. ¹H-NMR (CD₃OD) δ (ppm) : 1.8-2.1 (4H, m, 2CH₂), 2.32 (4H, t, 2CH₂), 2.63 (4H, t, 2CH₂), 6.84 (2H, d, arom-H), 6.9-7.2 (4H, m, arom-H) MS (FAB) : 357 (M-H)⁻ Reference Example 19 Synthesis of 2, 2'- dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl Thionyl chloride (0.208 ml, 2.793 mmol) was dropwise added to 2, 2'-dihydroxy-5, 5'-bis (3-carboxypropyl) biphenyl (100 mg, 0.2793 mmol) obtain in Reference Example 18, dissolved in methanol (2 ml) under cooling. The reaction mixture was stirred for several minutes and further agitated at room temperature for 1.5 hours. Solvent in the reaction mixture was evaporated off under reduced pressure, then the residue was dissolved in chloroform. The chloroform solution was washed with aqueous sodium bicarbonate, water and aqueous sodium chloride in this order, then dried by adding anhydrous sodium sulfate. The residue obtained by evaporating off the solvent was purified by silica-gel column chromatography (with 10 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 20/l) to obtain 101.2 mg (0.2622 mmol, 94 %) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.95 (4H, m, 2CH₂), 2.35 (4H, t, 2CH₂), 2.63 (4H, t, 2CH₂), 3.62 (6H , s, 2CH₃), 6.07 (2H, s, 2OH), 6.8-7.3 (6H, m, arom-H), MS (FAB) : 385 (M-H)⁻ Reference Example 20 Synthesis of 2, 2'-dihydroxy-5, 5'-bis (3-ethoxycarbonylpropyl) biphenyl Thionyl chloride (1.1 ml, 13.97 mmol) was dropwise added under cooling into 2, 2'-dihydroxy-5, 5'-bis (3-carboxypropyl) biphenyl (500 mg, 1.3966 mmol), obtained in Reference Example 18, dissolved in ethanol (50 ml). After agitating for several minutes, the reaction mixture was stirred at room temperature for 2 hours. Solvent in the reaction mixture was evaporated off under reduced pressure, and the residue was dissolved in chloroform. This solution was washed with dilute aqueous sodium bicarbonate, water and aqueous sodium chloride in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica-gel column chromatography (with 75 g of WAKO-gel C-200, eluent: chloroform and chloroform/methanol of 100/l) to obtain 435 mg (1.0507 mmol, 75 %) of 2, 2'-dihydroxy-5, 5'-bis (3- ethoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.25 (6H, t, 2CH₃), 1.9-2.1 (4H, m, 2CH₂), 2.35 (4H, t, 2CH₂), 2.65 (4H , t, 2CH₂), 4.09 (4H, t, 2CH₂), 5.86 (2H, s, 2OH), 6.9-7.2 (6H, m, arom -H), MS (FAB): 413 (M-H)⁻ Reference Example 21 Synthesis of 2- benzyloxy-2'- hydroxy-5, 5'-bis (3- ethoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.4831 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-ethoxycarbonylpropyl) biphenyl and 0.200 ml (1.681 mmol) of benzyl bromide, there were added 83 mg (0.6014 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 1 hour at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: chroloform) to obtain 208 mg (0.4127 mmol, 85 %) of acidified (using 1 N hydrochloric acid) 2-benzyloxy-2'-hydroxy-5, 5'-bis (2-ethoxycarbonyl-propyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.24 (6H, t, 2CH₃), 1.7-2.2 (4H, m, 2CH₂), 2.34 (4H, t, 2CH₂), 2.64 (4H , t, 2CH₂), 4.10 (2H, q, CH₂), 4.12 (2H, q, CH₂), 5.07 (2H, s, CH₂), 6.32 (1H, s, OH), 6.8-7.3 (11H, m, arom -H) MS (FAB): 503 (M-H)⁻ Reference Example 22 Synthesis of 2-(2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.731 ml (5.181 mmol) of 2-fluoro-4-bromobenzyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and the resulting mixture was agitated for 2 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l) to obtain 248.1 mg (0.4322 mmol, 83 %) of 2-(2-fluoro -4-bromobenzyloxy)-2'-hydroxy- 5, 5'-bis (3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.7-2.2 (4H, m, 2CH₃), 2.35 (4H, t, 2CH₂), 2.67 (4H, t, 2CH₂), 3.66 (6H , s, 2CH₃), 5.03 (2H, s, CH₂), 6.87 (1H, s, OH), 6.8-7.3 (9H, m, arom-H) MS (FAB) : 573 (M-H)⁻ Reference Example 23 Synthesis of 2- cyclohexylmethoxy-2'- hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy- 5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 1.46 ml (10.362 mmol) of cyclohexylmethyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated overnight at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/1) to obtain 215 mg (0.4454 mmol, 86 %) of 2-cyclohexylmethoxy-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.6-2.2 (15H, m, cyclohexyl-H, 2CH₂), 2.36 (4H, t, 2CH₂), 2.65 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 3.81 (2H, d, CH₂), 6.52 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 482 (M⁺) Reference Example 24 Synthesis of 2- methoxy-2'- hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5,-bis (3-methoxycarbonylpropyl) biphenyl and 0.329 ml (5.181 mmol) of methyl iodide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 4 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/l and 25/l) to obtain 159 mg (0.3975 mmol, 77 %) of 2-methoxy- 2'-hydroxy-5, 5'bis(3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.96 (4H, m, 2CH₂), 2.35 (2H, t, CH₂) , 2.36 (2H, t, CH₂), 2.63 (2H, t, CH₂) , 2.66 (2H, t, CH₂), 3.66 (6H, s, 2CH₃), 3.87 (3H, s, CH₃), 6.24 (1H, s, OH), 6.9-7.3 (6H, m, arom-H) MS (FAB) : 400 (M⁺) Reference Example 25 Synthesis of 2- ethoxy-2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.391 ml (5.181 mmol) of ethyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 5 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l) to obtain 184 mg (0.4444 mmol, 86 %) of 2-ethoxy-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.36 (3H, t, CH₃), 1.7-2.2 (4H, m, 2CH₂), 2.36 (4H, t, 2CH₂), 2.64 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 4.10 (2H, q, CH₂), 6.66 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 413 (M⁺) Reference Example 26 Synthesis of 2- propoxy-2'- hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.475 ml (5.181 mmol) of propyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 5 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/l) to obtain 202 mg (0.4720 mmol, 91 %) of 2-propoxy-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.94 (3H, t, CH₃), 1.6-2.2 (6H, m, 3CH₂), 2.36 (4H, t, 2CH₂), 2.65 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 3.99 (2H, t, CH₂), 6.60 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 427 (M-H)⁻ Reference Example 27 Synthesis of 2- butoxy-2'- hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0. 5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.562 ml (5.181 mmol) of butyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 4 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 20 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/l) to obtain 190 mg (0.4299 mmol, 83 %) of 2-butoxy-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.88 (3H, t, CH₃), 1.1-2.2 (8H, m, 4CH₂), 2.36 (4H, t, 2CH₂), 2.65 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 4.02 (2H, t, CH₂), 6.59 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 441 (M-H)⁻ Reference Example 28 Synthesis of 2- heptyloxy-2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.840 ml (5.181 mmol) of heptyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 5 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/l) to obtain 224 mg (0.4628 mmol, 89 %) of 2- heptyloxy- 2'-hydroxy- 5, 5'-bis (3- methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.85 (3H, t, CH₃), 1.0-2.2 (14H, m, 7CH₂), 2.35 (4H, t, 2CH₂), 2.64 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 4.01 (2H, s, CH₂), 6.61 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 483 (M-H)⁻ Reference Example 29 Synthesis of 2- octyloxy-2'- hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.895 ml (5.181 mmol) of octyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 5 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l) to obtain 236 mg (0.4738 mmol, 91 %) of 2 - octyloxy- 2'-hydroxy- 5, 5'-bis (3- methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.87 (3H, t, CH₃), 1.0-2.2 (16H, m, 8CH₂), 2.36 (4H, t, 2CH₂), 2.65 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 4.01 (2H, t, CH₂), 6.61 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 497 (M-H)⁻ Reference Example 30 Synthesis of 2- isopentyloxy-2'- hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.646 ml (5.181 mmol) of isopentyl bromide, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 5 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 50/l) to obtain 198 mg (0.4342 mmol, 84 %) of 2 -isopentyloxy-2'-hydroxy- 5, 5'-bis (3- methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.86 (6H, d, 2CH₃), 1.0-2.2 (7H, m, CH, 3CH₂), 2.35 (4H, t, 2CH₂), 2.64 (4H, t, 2CH₂), 3.66 (6H, s, 2CH₃), 4.04 (2H, t, CH₂), 6.58 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 455 (M-H)⁻ Reference Example 31 Synthesis of 2-(3-chloropropoxy)-2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl To 5 ml of a DMF solution containing 200 mg (0.5181 mmol) of 2, 2'-dihydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl and 0.646 ml (5.181 mmol) of 1-bromo-chloropropane, there were added 85.8 mg (0.6217 mmol) of anhydrous potassium carbonate and a small amount of copper powder and the resulting mixture was agitated for 5 hours at room temperature. The reaction mixture was filtered with sucking through Celite to remove the solid matter and the filtrate was washed with ethyl acetate. After the solvent in the filtrate was evaporated off under reduced pressure, the evaporated residue was dissolved in chloroform. This solution was washed with dilute hydrochloric acid, dilute aqueous sodium bicarbonate, water and aqueous sodium chloride solution in this sequence and was dried by adding anhydrous sodium sulfate. The residue obtained after the solvent had been evaporated off was purified by silica gel column chromatography (with 15 g of WAKO-gel C-200, eluent: toluene and toluene/ethyl acetate of 100/l) to obtain 206 mg (0.4454 mmol, 86 %) of 2 -(3-chloropropoxy-2'-hydroxy- 5, 5'-bis (3-methoxycarbonylpropyl) biphenyl as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.8-2.2 (6H, m, 3CH₂), 2.36 (4H, t, 2CH₂), 2.5-2.8 (4H, m, 2CH₂), 3.51 (2H, t, CH₂), 3.66 (6H, s, 2CH₃), 4.16 (2H, t, CH₂), 6.05 (1H, s, OH), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 461 (M-H)⁻ Example 18 Synthesis of 2- benzyloxy-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 3.1 ml of a methanol solution containing 130 mg (0.2579 mmol) of 2 -benzyloxy- 2'-hydroxy-5, 5'-bis (3-ethoxycarbonylpropyl) biphenyl obtained in Reference Example 21, 2.0 ml (2.000 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 103 mg (0.2299 mmol, 89 %) of 2 -benzyloxy-2'-hydroxy- 5, 5'-bis (3-carboxypropyl) biphenyl as an oily product. ¹H-NMR (MeOH-d₄) δ (ppm) : 1.7-2.2 (4H, m, 2CH₂), 2.2-2.4 (4H, m, 2CH₂), 2.4-2.7 (4H, m, 2CH₂), 5.01 (2H, s, CH₂), 6.7-7.3 (11H, m, arom-H) MS (FAB) : 447 (M-H)⁻ Example 19 Synthesis of 2- (2-fluoro-4-bromobenzyloxy)-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 13 ml of a methanol solution containing 233.2 mg (0.4062 mmol) of 2 -(2-fluoro-4-bromobenzyloxy-2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 22, 3.25 ml (3.25 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid and then hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium - sulfate. By evaporating off the solvent, 208.5 mg (0.3819 mmol, 94 %) of 2 -fluoro-4-bromobenzyloxy) -2'-hydroxy- 5, 5'-bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.8-2.2 (4H, m, 2CH₂), 2.38 (4H, t, 2CH₂), 2.66 (4H, t, 2CH₂), 5.05 (2H, s, CH₂), 6.8-7.3 (9H, m, arom-H) MS (FAB) : 545 (M-H)⁻ Example 20 Synthesis of 2- cyclohexylmethoxy -2'- hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 13 ml of a methanol solution containing 93.3 mg (0.1936 mmol) of 2 -cyclohexylmethoxy -2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 23, 3.3 ml (3.3 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 181 mg (0.3986 mmol, 97 %) of 2 -cyclohexylmethoxy-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.6-2.2 (15H, m, cyclohexyl-H, 2CH₂), 2.38 (4H, t, 2CH₂), 2.69 (4H, t, 2CH₂), 3.81 (2H, d, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 453 (M-H)⁻ Example 21 Synthesis of 2- methoxy-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 4.3 ml of an ethanol solution containing 143.5 mg (0.3588 mmol) of 2 -methoxy -2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 24, 1.4 ml (1.4 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 3 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 125.7 mg (0.3379 mmol, 94 %) of 2 -methoxy-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.97 (4H, m, 2CH₂), 2.39 (4H, t, 2CH₂), 2.68 (2H, t, CH₂), 2.69 (2H, t, CH₂), 3.88 (3H, s, CH₃), 6.9-7.3 (6H, m, arom-H) MS (FAB) : 372 (M)⁺ Example 22 Synthesis of 2 - ethoxy -2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 14 ml of an ethanol solution containing 171.2 mg (0.43355 mmol) of 2 - ethoxy -2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 25, 3.3 ml (3.3 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 160 mg (0.4145 mmol, 96 %) of 2 - ethoxy-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.25 (3H, t, CH₃) 1.8-2.2 (4H, m, 2CH₂), 2.40 (4H, t, 2CH₂), 2.69 (4H , t, 2CH₂), 4.12 (2H, q, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 385 (M-H)⁻ Example 23 Synthesis of 2-cyclohexylmethoxy -2'-hydroxy-5, 5'-bis (2-carboxypropyl) biphenyl To 20 ml of a methanol solution containing 198.5 mg (0.4638 mmol) of 2 -propoxy -2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 26, 3.7 ml (3.7 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 182.7 mg (0.4568 mmol, 98 %) of 2 -propoxy-2'-hydroxy-5, 5'- bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.93 (3H, t, CH₃), 1.5-2.2 (6H, m, 3CH₂), 2.38 (4H, t, 2CH₂), 2.67 (4H , t, 2CH₂), 3.98 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 399 (M-H)⁻ Example 24 Synthesis of 2 - butoxy -2'- hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 12 ml of a methanol solution containing 169.4 mg (0.3832 mmol) of 2 - butoxy -2'-hydroxy-5, 5'-bis (3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 27, 3.1 ml (3.1 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 155.4 mg (0.3753 mmol, 98 %) of 2 - butoxy- 2'-hydroxy-5, 5'- bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.88 (3H, t, CH₃), 1.1-2.2 (8H, m, 4CH₂), 2.39 (4H, t, 2CH₂), 2.68 (4H , t, 2CH₂), 4.03 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 413 (M-H)⁻ Example 25 Synthesis of 2 - heptyloxy -2'- hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 12 ml of a methanol solution containing 193.7 mg (0.4002 mmol) of 2 -heptyloxy -2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 28, 3.2 ml (3.2 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 178.5 mg (0.3914 mmol, 98 %) of 2-heptyloxy-2'-hydroxy-5, 5'- bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.85 (3H, t, CH₃), 1.0-2.2 (14H, m, 7CH₂), 2.39 (4H, t, 2CH₂), 2.68 (4H , t, 2CH₂), 4.02 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 455 (M-H)⁻ Example 26 Synthesis of 2 - octyloxy -2'- hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 14 ml of a methanol solution containing 210 mg (0.4220 mmol) of 2 -n-octyloxy-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 29, 3.4 ml (3.4 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 197.4 mg (0.420 mmol, 99 %) of 2-octyloxy-2'-hydroxy-5, 5,-bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.86 (3H, t, CH₃), 1.0-2.2 (16H, m, 8CH₂), 2.39 (4H, t, 2CH₂), 2.69 (4H , t, 2CH₂), 4.02 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 469 (M-H)⁻ Example 27 Synthesis of 2- isopentyloxy-2'- hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 12 ml of a methanol solution containing 182:4 mg (0.4000 mmol) of 2 -isopentyloxy-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 30, 3.2 ml (3.2 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 160 mg (0.3865 mmol, 97 %) of 2-isopentyloxy-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 0.87 (6H, d, 2CH₃), 1.1-2.2 (7H, m, 3CH₂, CH), 2.39 (4H, t, 2CH₂), 2.69 (4H, t, 2CH₂), 4.05 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 413 (M-H)⁻ Example 28 Synthesis of 2-(3-chloropropoxy)-2'-hydroxy-5, 5'-bis (3-carboxypropyl) biphenyl To 13 ml of a methanol solution containing 186.3 mg (0.4023 mmol) of 2 -(3-chloropropoxy)-2'-hydroxy-5, 5'-bis(3-methoxycarbonylpropyl) biphenyl obtained in Reference Example 31, 3.2 ml (3.2 mmol) of 1 N sodium hydroxide solution were added and the mixture was agitated at room temperature for 2 days. The solvent of the reaction mixture was evaporated off under reduced pressure and, to the resulting evaporated residue, water was added. The solution obtained was washed with ether and was then acidified using 1 N hydrochloric acid and then 0.1 N hydrochloric acid to a pH of about 3. The thereby formed precipitate was extracted with ethyl acetate and the extract was washed with water and then with aqueous sodium chloride and was then dried by adding anhydrous sodium sulfate. By evaporating off the solvent, 174.5 mg (0.4011 mmol, 99 % ) of 2-(3-chloropropoxy)-2'-hydroxy-5, 5'- bis (3-carboxypropyl) biphenyl were obtained as an oily product. ¹H-NMR (CDCl₃) δ (ppm) : 1.8-2.2 (6H, m, 3CH₂), 2.40 (4H, t, 2CH₂), 2.68 (4H, t, 2CH₂), 3.58 (2H , t, CH₂), 4.16 (2H, t, CH₂), 6.8-7.3 (6H, m, arom-H) MS (FAB) : 433 (M-H)⁻ Example 29 Production of Disodium salt of 2- methoxy-2'-hydroxy-5, 5'-bis(3-carboxypropyl) biphenyl 372 mg (1 mmol) of a compound 2-methoxy-2'-hydroxy-5, 5'-bis(3-carboxypropyl) biphenyl obtained in Example 21 were suspended in 50 ml of distilled water and the compound was dissolved by adding thereto 2 ml of 1 N NaOH aq. solution. The solution was concentrated by evaporation under a reduced pressure and was subjected to freeze-drying, whereby 415 mg of the title compound were obtained. In the same manner, as above, the compounds of formula (I) produced in Examples 1 - 20 and 22 - 28 were able to be converted into the corresponding disodium salts. Example 30 Encapsulated Preparation An encapsulated preparation was prepared by encapsulating 200 mg of the mixture of the following composition in each # 1 capsule. Composition Disodium salt of 2-methoxy-2'-hudroxy-5, 5'-bis(3-carboxypropyl) biphenyl 50 mg Lactose 50 mg Corn starch 80 mg Crystallized cellulose 16 mg Calcium stearate 4 mg

Claims: Claims for the following Contracting States : AT, BE, CH, DE, DK, FR, GB, IT, LI, LU, NL, SE A compound of formula (I): in which R is C₁₋₁₂ alkyl; lower alkyl wherein X₁ and X₂, which may be the same or different, are each hydrogen or a halogen; cyclohexylmethyl; cyclohexyl; tetrahydro-2H-pyran-1-yl-methyl; carboxy-lower alkyl or chloro-lower alkyl and each n, which may be the same or different, is 2 or 3, or a physiologically acceptable salt thereof. A process for preparing a compound of formula (I) as defined in claim 1, or a physiologically acceptable salt thereof, which comprises hydrolysing a compound of formula (II): wherein R and n are as defined in claim 1 and R₁ and R₂, which may be the same or different, are groups which are removable by hydrolysis, and, if desired, converting the compound of formula (I) thus obtained to a physiologically acceptable salt thereof A process according to claim 2 wherein R₁ and R₂ are lower alkyl. An aldose reductase inhibitor which comprises a compound of formula (I) as defined in claim 1 or a physiologically acceptable salt thereof, and a carrier. A compound of formula (I) as defined in claim 1 or a physiologically acceptable salt thereof for use in a method of treatment of the human or animal body by therapy. A compound of formula (I) as defined in claim 1 or a physiologically acceptable salt thereof for use in a method of treatment of a condition requiring an aldose reductase inhibitor. Use of a compound of formula (I) as defined in claim 1 or a physiologically acceptable salt thereof in the manufacture of a medicament for the treatment of a condition requiring an aldose reductase inhibitor. Claims for the following Contracting States : ES, GR A process for preparing a compound of formula (I): in which R is C₁₋₁₂ alkyl; lower alkyl wherein X₁ and X₂, which may be the same or different, are each hydrogen or a halogen; cyclohexylmethyl; cyclohexyl; tetrahydro-2H-pyran-1-yl-methyl; carboxy-lower alkyl or chloro-lower alkyl and each n, which may be the same or different, is 2 or 3, or a physiologically acceptable salt thereof, which process comprises hydrolysing a compound of formula (II): wherein R and n are as defined above and R₁ and R₂, which may be the same or different, are groups which are removable by hydrolysis, and, if desired, converting the compound of formula (I) thus obtained to a physiologically acceptable salt thereof A process according to claim 1 wherein R₁ and R₂, are lower alkyl. A process for preparing an aldose reductase inhibitor which comprises mixing together a compound of formula (I) as defined in claim 1 or a physiologically acceptable salt thereof, and a carrier. Use of a compound of formula (I) as defined in claim 1 or a physiologically acceptable salt thereof in the manufacture of a medicament for the treatment of a condition requiring an aldose reductase inhibitor.

Inventors: ASAHI AKIRA, KUNO KOUICHI, SHODA MOTOSHI, SUZUKI YUKIO, YAGINUMA SATOSHI, YASO MASAO, ASAHI, AKIRA, KUNO, KOUICHI, SHODA, MOTOSHI, SUZUKI, YUKIO, YAGINUMA, SATOSHI, YASO, MASAO
Applicants: ASAHI CHEMICAL IND, ASAHI KASEI KOGYO KABUSHIKI KAISHA
Application year: 1991
Main classification: C07C59
IPC codes: A61K31, A61P3, C07C69, C07C51, C07C59, C07D309, C12N9