USE OF 3,4-DIPHENYL CHROMANS FOR THE MANUFACTURE OF A PHARMACEUTICAL COMPOSITION FOR THE TREATMENT OR PROPHYLAXIS OF BENIGN PROSTATIC HYPERTROPHY

Abstract: The present invention provides novel uses of compounds of general formula (I) wherein R<1>, R<4> and R<5> are individually hydrogen, hydroxy, halogen, trifluoromethyl, C1-6-alkyl, C1-6-alkoxy or (tertiary amino)(C1-6-alkoxy); and R<2> and R<3> are individually hydrogen or C1-6-alkyl, or as a pharmaceutically acceptable salt thereof in combination with a pharmaceutically acceptable carrier for the manufacture of a pharmaceutical composition for the treatment or prophylaxis of benign prostatic hypertrophy.

Description: Use of 3,4-diphenyl chromans for the manufacture of a pharmaceutical composi¬ tion for the treatment or prophylaxis of benign prostatic hypertrophy FIELD OF THIS INVENTION The present invention relates to the use of compounds of the general formula I for the treatment of patients suffering from benign prostatic hypertrophy and prophylaxis hereof. The present invention also embraces pharmaceutical compo¬ sitions comprising these compounds and methods of using the compounds and their pharmaceutical compositions. BACKGROUND OF THIS INVENTION Benign prostatic hypertrophy is an almost universal phenomenon in aging men. It refers to a nodular enlargement of the gland due to hyperplasia of both glandular and stromal components. The incidence of this disease is only 8% during the fourth decade, but it reaches 50% in the fifth decade and 75% in the eighth de¬ cade. The disorder is not a major cause of death, but it is a leading cause of morbidity in elderly men. The pathogenesis is not well-understood, but dihydro- testosterone together with increasing levels of estrogen which occur in men act synergistically to induce prostatic growth. The treatment is surgical, which, however, can only be offered to a small selected number of patients with this disease because the majority of men above age 60 have some degree of prosta¬ tic hyperplasia. No protecting factors other than castraction have been identified and no effective pharmacological treatment or profylaxis exists. Centchroman is a non-steroidal compound known to have antiestrogenic activity. It is in use in India as an oral contraceptive (see, for example, Salman et al., U.S. Patent Specification No. 4,447,622; Singh et al., Acta Endocrinal (Copenh. 1 26 ( 1 992), 444 - 450; Grubb, Curr Opin Obstet Gynecol 3 ( 1 991 ) . 491 - 495; San- karan et al., Contraception 9 ( 1 974), 279 - 289; Indian Patent Specification No. 1 291 87) . Centchroman has also been investigated as an anti-cancer agent for treatment of advanced breast cancer (Misra et al., Int J Cancer 43 ( 1 989), 781 - 783. Recently, centchroman as a racemate has been found as a potent choleste¬ rol lowering pharmaceutical expressed by a significant decrease of the serum concentrations (S.D. Bain et al. , . Mn β__D B≤≤ 3 ( 1 994), S 394). U.S. patent 5,453,442 describes methods of lowering serum cholesterol and in¬ hibiting smoother muscle cell proliferation in humans and inhibiting uterine fibroid disease and endometriosis in women by administering compounds of formula I as shown therein. Furthermore, US patent 5,280,040 describes methods and phar¬ maceutical compositions for reducing bone loss using 3,4-diaryl chromans and their pharmaceutically acceptable salts. There is no disclosure in the patents of using the compounds to treat or prevent benign prostatic hypertrophy. One object of the present invention is to provide compounds which can effecti¬ vely be used in the treatment or prophylaxis of benign prostatic hypertrophy. BRIEF DESCRIPTION OF THIS INVENTION It has, surprisingly, been found that compounds of the general formula I as sta¬ ted in claim 1 can be used in the treatment or prophylaxis of benign prostatic hypertrophy. DETAILED DESCRIPTION OF THIS INVENTION The present invention is based in part on the discovery that a representative 3,4- diarylchroman, centchroman (3,4-trans-2,2-dimethyl-3-phenyl-4-[p-(beta- pyrrolidinoethoxy)phenyl]-7-methoxychroman) is effective against benign prosta¬ tic hypertrophy, inter alia in rats. An increased prostate weight is the cardinal observation seen in patients with prostatic hypertrophy, hence these data thus indicate that the 3,4-diarylchromans are useful as therapeutic agents against be ¬ nign prostatic hypertrophy in mammals, including primates such as humans. Within the present invention, compounds of formula I or their pharmaceutically acceptable salts are used for the treatment or prophylaxis of benign prostatic hypertrophy in a pa¬ tient. Within formula I, R R^ and R^ are individually hydrogen, hydroxy, halogen, trifluoromethyl, C,. 6 -alkyl, C^-alkoxy or (tertiary aminoMC^-alkoxy); and R^ and R^ are individually hydrogen or a C^-alkyl. As used herein, the term "C^-alkyl" includes straight and branched chain alkyl radicals containing from 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-amγl, sec- amyl, n-hexyl, 2-ethylbutyl, 2,3-dimethylbutyl and the like. The term "C,. 6 - alkoxy" includes straight and branched chain alkoxy radicals containing from 1 to 6 carbon atoms, such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, n-amyloxy, sec-amyloxy, n-hexyloxy, 2-ethylbutoxy, 2,3- dimethylbutoxy and the like. "Halogen" includes chloro, fluoro, bromo and iodo. Herein, the term "(tertiary aminoHC^e-alkoxy)" is a C 1 6 -alkoxy group which is substituted by a tertiary amino radical. The tertiary amino radical may be a N,N- dialkylamine such as a N,N-dimethylamino, N,N-diethylamino, N,N-dipropylamino. and N,N-dibutylamino or a polymethyleneimine, e.g., piperidine, pyrrolidine, N- methylpiperazine or morpholine. Preferred compounds include those in which R ' is C Lg -alkoxy; R 2 and R^ are C,. 6 -alkyl, especially methyl; R 4 is hydrogen; and R 5 is (tertiary aminoXC^-alkoxy) of the polymethyleneimine type. Within particu¬ larly preferred embodiments, R ^ is in the 7-position and is C,. 6 -alkoxy, particu¬ larly methoxy; each of R 2 and R^ is methyl, R 4 is hydrogen, and R 5 is in the 4- position and is a (tertiary amino)(C,. 6 -alkoxy) radical such as 2-(pyrrolidin-1 - yDethoxy with formula II To be included by this invention are all pharmaceutically acceptable salts of the mentioned compounds of formula I. It is preferred to use the compounds of formula I in the transconfiguration. These compounds may be used as racemic mixtures, or the isolated d- or I- enantiomers may be used. The trans-l-enantiomers are more preferred. A particularly preferred compound for use within the present invention is cen¬ tchroman having the formula IV Although only one enantiomer is shown, it will be understood that the formula IV is used herein to designate the transconfiguration of the 3- and 4-phenyl groups and that both the d- and l-enantiomers, as well as the racemic mixture, are inclu ded. 3,4-diarylchromans are prepared according to known methods, such as those di¬ sclosed in U.S. Patent Specification No. 3,340,276 to Carney et al., U.S. Patent Specification No. 3,822,287 to Bolger, and Ray et al., J Med Chem 1 9 ( 1 976), 276 - 279, the contents of which are incorporated herein by reference. Conver- sion of the cis isomer to the trans configuration by means of an organometallic base-catalyzed rearrangement is disclosed in U.S. Patent Specification No. 3,822,287. The optically active d- and l-enantiomers may be prepared as disclo¬ sed by Salman et al. in U.S. Patent Specification No. 4,447,622 (incorporated herein by reference) by forming an optically active acid salt which is subjected to alkaline hydrolysis to produce the desired enantiomer. If R2 is different from R3 and R4 is different from R5, the general formula I covers 8 optical isomers. Within the present invention, 3,4-diarylchromans of formula I may be prepared in the form of pharmaceutically acceptable salts, especially acid-addition salts, in- eluding salts of organic acids and mineral acids. Examples of such salts include salts of organic acids such as formic acid, fumaric acid, acetic acid, propionic a- cid, glycolic acid, lactic acid, pyruvic acid, oxalic acid, succinic acid, malic acid, tartaric acid, citric acid, benzoic acid, salicylic acid and the like. Suitable inorga¬ nic acid-addition salts include salts of hydrochloric, hydrobromic, sulphuric and phosphoric acids and the like. The acid addition salts may be obtained as the di¬ rect products of compound synthesis. In the alternative, the free base may be dissolved in a suitable solvent containing the appropriate acid, and the salt isola¬ ted by evaporating the solvent or otherwise separating the salt and solvent. 3,4-diarylchromans of formula I and their salts are useful within human and vete¬ rinary medicine, for example, in the treatment of patients suffering from benign prostatic hypertrophy. For use within the present invention, 3,4-diarylchromans of formula I and their pharmaceutically acceptable salts are formulated with a pharmaceutically acceptable carrier to provide a medicament for parenteral, oral, nasal, rectal, subdermal or intradermal or transdermal administration according to conventional methods. Formulations may further include one or more diluents, fillers, emulsifiers, preservatives, buffers, excipients, etc. and may be provided in such forms as liquids, powders, emulsions, suppositories, liposomes, transdermal patches, controlled release, dermal implants, tablets, etc. One skilled in this art may formulate the compounds of formula I in an appropriate manner, and in ac- cordance with accepted practices, such as those disclosed in Remington's Phar¬ maceutical Sciences. Gennaro, ed. , Mack Publishing Co., Easton, PA, 1 990. Oral administration is preferred. Thus, the active compound of formula I is prepa¬ red in a form suitable for oral administration, such as a tablet or capsule. Typi- cally, a pharmaceutically acceptable salt of the compound of formula I is com¬ bined with a carrier and moulded into a tablet. Suitable carriers in this regard in¬ clude starch, sugars, dicalcium phosphate, calcium stearate, magnesium stearate and the like. Such compositions may further include one or more auxiliary sub¬ stances, such as wetting agents, emulsifiers, preservatives, stabilizers, colouring additives, etc. Pharmaceutical compositions containing a compound of formula I may be admini¬ stered one or more times per day or week. An effective amount of such a phar¬ maceutical composition is the amount that provides a clinically significant effect against benign prostatic hypertrophy. Such amounts will depend, in part, on the particular condition to be treated, age, weight, and general health of the patient, and other factors evident to those skilled in the art. A typical daily dose will con¬ tain a nontoxic dosage range of from about 0.001 to about 75 mg/kg patient per day of a compound of the present invention. The pharmaceutical compositions containing a compound of formula I may be administered in unit dosage form one or more times per day or week. In the al ¬ ternative, they may be provided as controlled release formulations suitable for dermal implantation. Implants are formulated to provide release of active com¬ pound over the desired period of time, which can be up to several years. Con- trolled-release formulations are disclosed by, for example, Sanders et al., J Pharm Sci 73 (1 964), 1 294 - 1 297, 1 984; U.S. Patent Specification No. 4,489,056; and U.S. Patent Specification No. 4,210,644, which are incorpora¬ ted herein by reference. The following examples are offered by way of illustration, not limitation. Examples of preferred compounds of formula I are centchroman as a racemic mixture and as isolated l-centchroman and d-centchroman enantiomers. Further- more, 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 -yl)ethoxy)phenyl]-7- hydroxychroman is a preferred compound. The more preferred compound is isola¬ ted l-centchroman (l-3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 - yl)ethoxy)phenyl]-7-methoxychroman). Examples of pharmaceutically acceptable acid addition salts are salts with non- toxic acids, either inorganic acids such as hydrochloric acid, sulphuric acid and phosphoric acid, or organic acids such as formic acid, fumaric acid, acetic acid, propionic acid, succinic acid, gluconic acid, lactic acid, citric acid, ascorbic acid, benzoic acid, embonic acid, methanesulphonic acid and malonic acid. The present invention is further illustrated by the following examples which, however, are not to be construed as limiting the scope of protection. The fea¬ tures disclosed in the foregoing description and in the following examples may, both separately and in any combination thereof, be material for realising the in- vention in diverse forms thereof. PC17DK97/ 00011 8 Example 1 Sixty sexually mature male Sprague-Dawley rats were assigned to one of the following five treatment groups ( 1 2 rats per group): Dsaline, 2) l-centchroman 0.025 mg/kg/day, 3) l-centchroman 0.1 25 mg/kg/day, 4) l-centchroman 0.625 mg/kg/day and 5) l-centchroman 3.1 25 mg/kg/day. The doses were administered three times per week for 1 3 weeks by oral gavage. At the conclusion of the ex¬ periment and autopsy was performed, the prostate gland and testes were isola¬ ted and weighed. L-centchroman had no effect on the average testis weight between the groups. However, a marked and dose-dependent effect on the prostate gland was obser¬ ved as illustrated in Table 1 . Table 1 . Effect of l-centchroman on prostate gland weight in Sprague-Dawley rats Treatment Prostate gland (g) Saline 0.639 ± 0.239 l-centchroman 0.025 mg/kg/day 0.669 ± 0.1 49 l-centchroman 0.1 25 mg/kg/day 0.472 ± 0.1 26 * l-centchroman 0.625 mg/kg/day 0.430 ± 0.1 22 _ l-centchroman 3.1 25 mg/kg/day 0.368 ± 0. 1 24* Values are mean ± SD. * indicate significant reduction of prostate gland weight compared to saline treated rats.

Claims: CLAIMS 1 . The use of compounds of the general formula I wherein R1 , R4 and R5 are individually hydrogen, hydroxy, halogen, trifluoro¬ methyl, C,. 6 -alkyl, C,. 6 -alkoxy or (tertiary aminoMC^-alkoxy); and R2 and R3 are individually hydrogen or C^-alkyl, or as a pharmaceutically acceptable salt there¬ of in combination with a pharmaceutically acceptable carrier for the manufacture of a pharmaceutical composition for the treatment or prophylaxis of benign pro- static hypertrophy. 2. The use, according to claim 1 , wherein R1 in the compound used is C 6 - alkoxy, R2 and R3 are C^-alky!, R4 is hydrogen and R5 is (tertiary amino) C,. 6 - alkoxy. 3. The use according to any one of claims 1 or 2 wherein R 1 is methoxy. 4. The use according to any one of claims 1 -3 wherein R2 is methyl. 5. The use according to any one of claims 1 -4 wherein R3 is methyl. 6. The use according to any one of claims 1 -5 wherein R4 is hydrogen. 7. The use according to any one of claims 1 -6 wherein R5 is a group as sta¬ ted in formula II below: -o (II) 8. The use according to any one of claims 1 -7 wherein said compound is an isolated d- or l-enantiomer. 9. The use according to any one of claims 1 -8 wherein said compound has the general formula III as stated below: wherein R1 , R2, R3, R4 and R5 each are as defined in above claim 1 1 0. The use according to anyone of the preceding claims wherein said com¬ pound is 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 -yl)ethoxy)phenyl]- 7-hydroxychroman. 1 1 . The use according to anyone of the preceding claims wherein said com¬ pound is an isolated l-enantiomer. 1 2. The use according to claim 1 wherein said compound is centchroman 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 -yl)ethoxy)phenyl]-7- methoxychroman having the formula IV as stated below: 1 3. The use according to claim 1 2 wherein said compound is an isolated I- enantiomer of 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 - yl)ethoxy)phenyl]-7-methoxychroman. 14. The use according to any one of the preceding claims wherein said com¬ position is in a form suitable for oral administration. 1 5. The use according to any one of the preceding claims wherein said com- pound is administered as a dose in a range from about 0.001 to 75 mg/kg pa¬ tient per day. 1 6. The use according to any one of the preceding claims wherein said com¬ position is administered one or more times per day or week. 1 7. The use according to any one of the preceding claims wherein said com¬ position is in the form of a dermal implant. 1 8. Method for treatment and prophylaxis of benign prostatic hypertrophy comprising administering to a patient a clinically effective amount of a compound of above formula I stated to be used in any of the preceding use claims, or a pharmaceutically acceptable salt thereof in an amount sufficient to treat or pre¬ vent benign prostatic hypertrophy. 1 9. A method of treating or preventing benign prostatic hypertrophy which method comprises administering a clinically effective amount of compounds and pharmaceutically acceptable compositions, according to previous claims to a pa¬ tient in need of such a treatment. 20. Any novel feature or combination of features described herein. 07-01-1997 , PiSt/KGF 4611-WO

Inventors: CHRISTENSEN NIELS DYHR, GULDHAMMER BIRGITTE HJORT, KORSGAARD NIELS, SHALMI MICHAEL, CHRISTENSEN, NIELS, DYHR, GULDHAMMER, BIRGITTE, HJORT, KORSGAARD, NIELS, SHALMI, MICHAEL
Applicants: NOVONORDISK AS, NOVO NORDISK A/S
Application year: 1997
Main classification: A61K31
IPC codes: A61K31, A61P15, C07D311