NEW USE OF CATECHOL-O-METHYL TRANSFERASE (COMT) INHIBITORS AND THEIR PHYSIOLOGICALLY ACCEPTABLE SALTS AND ESTERS

Abstract: Catechol derivatives which have been previously suggested for the treatment of Parkinsonism are useful in the treatment and prophylaxis of ulcers and lesions.in the gastrointestinal tract.

Description: The present invention relates to use of catechol-O-methyl transferase (COMT) inhibitors. Such compounds are known and have been described e.g. in Finnish patent application 864875 and in European paten application 237929 as COMT inhibitors and they have been shown to be effective medicaments for treating for instance, Parkinsonism. It has now unexpectedly been found that COMT-inhibitors may be used for the treatment and prophylaxis of ulcers and lesions in the gastrointestinal tract. The above compounds may be shown by following general formula I wherein R₁ and R₂ independently comprise hydrogen, alkyl, optionally substituted acyl or optionally substituted aroyl, lower alkylsulfonyl or alkylcarbamoyl or taken together form a lower alkylidene or cycloalkylidene group, X comprises electronegative substituent such halogen, nitro, cyano, lower alkylsulfonyl, sulfonamido, trifluoromethyl, aldehyde or carboxyl and R₃ comprises hydrogen, halogen, substituted alkyl, hydroxyalkyl, nitro, cyano, optionally substituted amino, trifluoromethyl, lower alkylsulfonyl, sulfonamido, aldehyde, alkylcarbonyl, aralkylidenecarbonyl or carboxyl group or a group selected from wherin R₄ comprises hydrogen, alkyl, amino, cyano, carboxyl or acyl and R₅ comprises hydrogen, amino, cyano, carboxyl, alkoxycarbonyl, carboxyalkenyl, nitro, acyl, hydroxyalkyl, carboxyalkyl, COZ, wherein Z is an optionally substituted heterocyclic ring or one of following optionally substituted groups; carboxamido, carbamoyl, aroyl or heteroaryl or R₄ and R₅ together form a five to seven membered substituted cycloalkanone ring; -(CO) n (CH₂) m -COR wherein n is 0-1, m is 0-7 and R comprises alkyl, hydroxy, carboxyalkyl, optionally substituted alkene, optionally substituted heterocyclic ring, alkoxy or substituted amino; wherein R₈ and R₉ independently comprise hydrogen or one of the following optionally substituted groups; alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl or taken together form an optionally substituted piperidyl group; -NH-CO-R₁₀ wherein R₁₀ comprises a substituted alkyl group; -(A) p -(Q) r -R₁₁ or -(A) p -Q-R₁₂ wherein p is 0 or 1, r is 0 or 1, A comprises a vinylene group, optionally substituted with lower alkyl, R₁₁ comprises -COR₁₃, carbocyclic, aromatic group or aromatic or partially unsaturated heterocyclic group bound through a carbon atom, R₁₂ comprises hydrogen or an optionally substituted saturated or partially unsaturated lower hydrocarbon rest, R₁₃ comprises hydroxy, amino, optionally substituted saturated or or partially unsaturated lower hydrocarbon rest being bound by the aid of an oxygen atom or an imino or lower alkyl-imino group or a saturated nitrogen containing heterocyclic group bound through the nitrogen atom in the ring, Q comprises -CO or >C=N-(B) s -R₁₄, wherein B comprises an oxygen atom or an imino group, s is 0 or 1 and R₁₄ comprises hydrogen, an optionally substituted saturated or partially unsaturated lower hydrocarbon rest optionally bound through a carbonyl group. In the above patent application it has been described several methods for the preparation of the compounds according to formula I. The methods for the preparation of esters which, when given to a patient, mostly hydrolyse readily to the active compound have been described in these publications too. Salts of these compounds, when applicable, may be prepared by known methods. All physiologically acceptable salts are useful as active medicaments, however, preferred are the salts with hydrochloric, hydrobromic, phosphoric and sulfuric acids and with the organic acids like oxalic, fumaric, tartaric, malonic, acetic and citric acids. Peptic ulcer is a pluricausal disease the pathogenesis and cause of which are not yet fully understood. Duodenal ulcer is the most prevalent form of peptic ulcers. Thus cycteamine-induced duodenal ulcer in rats, an animal model which morphologically and functionally resembles human duodenal ulcer ( Szabo, S. Lab. Invest. 51:121-147, 1984 ), has offered a useful possibility to test the antiulcer drugs and study the pathophysiology of ulceration. Besides of known antiulcer drugs, also dopamine and dopamine agonists are found to be protective in this animal model, whereas dopamine antagonists aggravate the ulcers ( Horner, H.C., Szabo, S., Life Sci. 29:2437-2443, 1981 ). Decreased dopamine levels after cysteamine are detected in gastric and duodenal mucosa ( Szabo, S. et al. J.Pharmacol. Exp. Ther. 240:871-878, 1987 ). Dopamine is also known to influence the gastric secretion, gastroduodenal motility and intestinal blood flow, which are all involved in the pathogenesis of ulceration. The present compounds are effective in treating various conditions in which lesions are located in the oesophagus, stomach, small intestine, colon or rectum or for prophylaxis of the lesions in the gastrointestinal tract. Illnesses which at least can be treated with the compounds are for instance ulcers in the oesophagus, duodenal or ventrical ulcers, gastritis, ulcerative colitis or ulcers in the rectum or minor lesions in the gastrointestinal tract. In the preferred compounds X is nitro or cyano especially in the 5-position. In these compounds R₃ is especially nitro, cyano, halogen or a group which has a conjugated double bond system with the double bonds of the aromatic ring whereto R₃ is attached. Thus preferred compounds are for instance those having R₃ which begins with a single bond (the attaching bond) and continues with a double bond in the main chain or in the side chain. The double bonds are in many cases located between two carbon atoms or between carbon atom and oxygen atom. Because the conjugated system may be quite long, there may be also present both types of double bonds and also rings having double bonds may be involved in the conjugated system. The effective dose varies considerably depending of whether the compounds are given for prophylaxis or for treatment of peptic ulcers. The daily dose and the number of the doses are dependent of the severity of the illness to be treated. As far as it is possible now to predict the effective dose for human beings, it may be said that the effective dose is from about 1 to 100 mg per day once a day or divided into several doses. The preferred dose may be from 10 to 60 mg per day. The compounds according to this invention are formulated into dosage forms using the principles which are known to the man having average skills in the art. The compounds according to this invention are given to a patient as such or in combination with suitable pharmaceutical material in the form of tablets, dragees, capsules, suppositories, emulsions, suspensions or solutions whereby the contents of the active compound is in the formulation from 1 to 100 weight-%. Choosing the auxiliary ingredients for the formulation is a task of the experienced staff in the art. It is evident that suitable solvents, gel forming ingredients, dispersion forming ingredients, antioxidants, colours etc are used in a normal way. The compositions are given enterally or parenterally, the oral way being the easiest and preferred way. The compositions are formulated for the purpose of the medicine, normal uncoated tablets being quite satisfactory when lesion located in the stomach area are treated. When the lesions are located in the small intestine or in the colon it is advisable to use coated tablets, so called enterotablets to secure that the medicine reaches the desired part of the gastrointestinal tract. When the lesion of rectum are treated, suppositories are the normal way to give the medicine. Suppositories are also given when the desired systemic effect is desired with patients having nausea. Example 1 Cysteamine-induced duodenal ulcer in rats Cysteamine-induced duodenal ulcer in rats resembles morphologically and functionally human duodenal ulcer. All known antiulcer drugs are found to be effective in this model. Test compounds were administered orally half an hour before s.c. cysteamine 425 mg/kg. The rats were sacrificed 24 hours after cysteamine and the ulcer index for the duodenum was calculated. The ulcer index is the sum of 1) percent incidence (divided by 10) of animals with ulcers, 2) average severity of ulcers per rat for each group, 3) average number of duodenal ulcers per rat for each group. The severity of ulcers was evaluated on a scale of 0 to 3, where 0 = normal duodenum, 1 = erosion (lesion limited to mucosa), 2 = deep ulcer involving the muscularis propria, 3 = penetrated or perforated ulcer. The results are summarized in TABLE 1. The preventing effect of the catechol derivatives on cysteamine-induced duodenal ulcer after a single dose. Control OR-462 OR-486 dose mg/kg p.o. 10 30 10 30 n 11 8 8 8 7 Incidence of ulcers (%) 91 75 25 63 43 Severity of ulcers (0-3) 1.8 1.3 0.4 0.7 0.4 Number of ulcers in duodenum 1.9 0.9 0.4 1.0 0.6 Ulcer index 12.8 9.7 3.3 8.0 5.3 Reduction (%) 24 74 38 59 OR-462 = 3-(3,4-dihydroxy-5-nitrobenzylidene)-2,4-pentanedione OR-486 = 3,5-dinitrocatechol Example 2 In this example the compounds were dosed twice, the first dose was administered as in Example 1 and the other dose was given again 5 hours after cysteamine. The rats were sacrificed 24 hours after cysteamine and the ulcer index for the duodenum was calculated as in Example 1. The results are given in TABLE 2. The preventing effect of OR-462 b.i.d. on cysteamine-induced duodenal ulcer. Control OR-462 dose mg/kg p.o. 2x5 2x10 n 8 8 8 Incidence of ulcers (%) 100 50 38 Severity of ulcers (0-3) 1.8 0.8 0.9 Number of ulcers in duodenum 1.9 0.5 0.6 Ulcer index 13.7 6.3 5.3 Reduction (%) 54 61 The compounds OR-462 and OR-486 significantly reduced both incidence and severity of cysteamine-induced duodenal ulcers. When administered twice a day the potency of OR-462 was even more pronounced. The results indicate a possible effect of these compounds also in human duodenal ulcer. Example 3 Ethanol-induced gastric lesions in rats Oral administration of absolute ethanol to rats results in severe gastric damage consisting of grossly hemorrhagic and necrotic lesions. Rats were orally dosed with test compounds. Half an hour later the rats were orally administered with 1 ml of absolute ethanol. The animals were sacrificed one hour after ethanol and the total area of lesions in each stomach was examined. The results are given in TABLE 3. The effect of the catechol derivatives on the area of ethanol-induced gastric damage in rats. Control OR-462 OR-486 dose mg/kg p.o. 10 30 10 30 n 20 8 7 8 8 Area of lesions 92.4 58.1 35.3 55.1 15.3 SE ± 9.5 ± 18.5 ± 8.9 ± 5.4 ± 7.7 Inhibition % 37 62 40 83 Both compounds, OR-462 and OR-486 reduced significantly the area involved in ethanol-induced gastric lesions. This finding implies a cytoprotective effect of these compounds. The compounds were: A) 3-(3-hydroxy-4-methoxy-5-nitrobenzylidene)-2,4-pentanedione B) 3-(4-hydroxy-3-methoxy-5-nitrobenzylidene)-2,4-pentanedione C) 3-(3-chloro-5-ethoxy-4-hydroxybenzylidene)-2,4-pentanedione D) 3-(3-chloro-4,5-dihydroxybenzylidene)-2,4-pentanedione Example 4 An oral composition in the form of a tablet was made in accordance with the following formulation. The effective compound (e.g. OR-462) 30.0 mg Lactos. 120.0 mg Mayd.amyl. 65.0 mg Gelatin 4.5 mg Aq.purif. about 44.0 mg Mayd.amyl. 10.0 mg Talc. 9.0 mg Magn. stear. 1.8 mg The procedure was so called Glatt-process in which the active ingredient is first granulated with the auxiliary ingredients and the granules are then pressed into tablets.

Claims: Use of a catechol-O-methyl transferase (COMT) inhibitor or a physiologically acceptable salt or ester thereof for the manufacture of a medicament for the treatment or prophylaxis of ulcers or lesions in the gastrointestinal tract. Use according to claim 1 in which the said COMT-inhibitor is a compound of the formula: wherein R₁ and R₂ independently comprise hydrogen, alkyl, optionally substituted acyl or optionally substituted aroyl; X comprises an electronegative substituent such as halogen, nitro, cyano or carboxyl; and R₃ comprises halogen, substituted alkyl, nitro, cyano, alkylcarbonyl, aralkylidenecarbonyl or a group selected from wherein R₄ comprises hydrogen, alkyl, amino, cyano or acyl and R₅ comprises hydrogen, cyano, carboxyl, alkoxycarbonyl, carboxyalkenyl, nitro, acyl, hydroxyalkyl, carboxyalkyl, COZ, wherein Z is an optionally substituted heterocyclic ring or one of following optionally substituted groups: carboxamido, carbamoyl, aroyl or heteroaryl; -(CO) n (CH₂) m -COR wherein n is 0-1, m is 0-7 and R comprises alkyl, hydroxy, optionally substituted alkene, an optionally substituted heterocyclic ring, alkoxy or substituted amino; wherein R₈ and R₉ independently comprise hydrogen or one of the following optionally substituted groups: alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl or taken together form an optionally substituted piperidyl group: - (A) p -R₁₁ or -(A) p -Q-R₁₂ wherein p is 0 or 1, A comprises a vinylene group, optionally substituted with alkyl of 1 to 4 carbon atoms, R₁₁ comprises a carbocyclic, aromatic group or partially unsaturated heterocyclic group bound through a carbon atom, R₁₂ comprises hydrogen or substituted saturated or partially unsaturated lower hydrocarbon residue of 1 to 4 carbon atoms, and Q comprises -CO; or a physiologically acceptable salt or ester thereof. Use according to claim 1 in which the COMT-inhibitor has the formula: wherein R₁ and R₂ are each hydrogen, alkyl of 1 to 4 carbon atoms or alkanoyl of 1 to 4 carbon atoms and R₃ is hydrogen chlorine, nitro, cyano, a radical of formula: or a radical of formula: -(CH₂) m -COR wherein R₄ is hydrogen, cyano, alkyl of 1 to 4 carbon atoms, or alkanoyl of 1 to 4 carbon atoms and R₅ is cyano, alkanoyl of 1 to 4 carbon atoms, alkyl of 1 to 4 carbon atoms, hydroxyalkyl of 1 to 4 carbon atoms or carboxyl, m is an integer from 0 to 7 and R is hydrogen, hydroxy, alkyl of 1 to 4 carbon atoms, or an amino radical of formula: where R₈ and R₉ are each hydrogen, alkyl of 1 to 4 carbon atoms, alkenyl of 2 to 4 carbon atoms, alkynyl of 2 to 4 carbon atoms, or adamantyl. Use according to claim 2, in which, in the compound according to formula I, X is nitro. Use according to claim 2, in which, in the compound according to formula I, X is cyano. Use according to claim 2, in which, in the compound according to formula I, R₃ is nitro, cyano, halogen or a group having at least one double bond which forms a conjugated system with the double bonds of the ring whereto R³ is attached. Use according to claim 6, in which, in the said compound the double bonds are formed between two carbon atoms or between a carbon atom and an oxygen atom. Use according to claim 1, in which the compound used is 3,5-dinitrocatechol. Use according to claim 1, in which the compound used is 3-(3,4-dihydroxy-5-nitrobenzylidene)-2,4-pentanedione. Use according to claim 1, in which the compound used is 3,4-dihydroxy-5-nitro-ω,ω-dicyanostyrene. Use according to claim 1, in which the compound used is 4-(3,4-dihydroxy-5-nitrophenyl)-3-methylbut-3-en-2-one. Use according to claim 1, in which the compound used is 3-(3,4-dihydroxy-5-nitrophenyl)-1-(3,4,5-trimethoxyphenyl)-prop-2-en-1-one. Use according to claim 1, in which the compound used is 3-(3,4-dihydroxy-5-nitrophenyl)-1-phenylprop-2-en-1-one. Use according to claim 1, in which the compound used is N-methyl-N-propargyl-5-(3,4-dihydroxy-5-nitrophenyl)-pentanoic acid amide. Use according to claim 1, in which the compound used is 4-(3,4-dihydroxy-5-nitrophenyl)-3-methylbut-3-en-2-ol. Use according to claim 1, in which the compound used is N-(1-adamantyl)-5-(3,4-dihydroxy-5-nitrophenyl)pentanoic acid amide. Use according to claim 1, in which the compound used is N-isopropyl-5-(3,4-dihydroxy-5-nitrophenyl)pentanoic acid amide. Use according to claim 1, in which the compound used is 4-hydroxy-3-methoxy-5-nitrocinnamic acid. Use according to claim 1, in which the compound used is 5-(3,4-dihydroxy-5-nitrophenyl)pentanoic acid. Use according to claim 1, in which the compound used is 2,5-bis-(3,4-dihydroxy-5-nitrobenzylidene)cyclopentanone. Use according to claim 1, in which the compound used is 2-propionyloxy-6-nitrophenol. Use according to claim 1, in which the compound used is 1,2-diacetoxy-3,5-dinitrobenzene. Use according to claim 1, in which the compound used is 3',4'-dihydroxy-5'-nitroacetophenone. Use according to claim 1, in which the compound used is 3,4-dihydroxy-5-nitrobenzaldehyde. Use according to claim 1, in which the compound used is 3,4-dihydroxy-5-nitrobenzonitrile. Use according to claim 1, in which the compound used is 4-chloro-6-nitrocatechol. Use according to claim 1, in which the compound used is 1,2-dipropionyloxy-3,5-dinitrobenzene. Use according to claim 1, in which the compound used is 2-pivaloyloxy-4,6-dinitrophenol. Use according to claim 1, in which the compound used is 3-(3-hydroxy-4-methoxy-5-nitrobenzylidene)-2,4-pentanedione. Use according to claim 1, in which the compound used is 3-(4-hydroxy-3-methoxy-5-nitrobenzylidene)-2,4-pentanedione. Use according to claim 1, in which the compound used is 3-(3-chloro-5-ethoxy-4-hydroxybenzylidene)-2,4-pentanedione. Use according to claim 1, in which the compound used is 3-(3-chloro-4,5-dihydroxybenzylidene)-2,4-pentanedione.

Inventors: AHO, PAIVI, BACKSTROM, REIJO, HONKANEN, ERKKI, LINDEN, INGE-BRITT, NISSINEN, ERKKI, POHTO, PENTTI
Applicants: ORION YHTYMAE OY, ORION-YHTYMAE OY
Application year: 1988
Main classification: A61K31
IPC codes: A61K31, C07D317, C07C205, A61P1, C07D295, C07C255