USE OF 2-OXO-IMIDAZOLIDINE DERIVATIVES IN THE TREATMENT OF KIDNEY DISEASES

Abstract: Novel agent for the treatment of kidney diseases, which comprises as an active ingredient a 2-oxo-imidazol­ idine compound of the formula: wherein R¹ is a lower alkyl group, R² is a lower alkyl group, R³ is a phenyl-substituted lower alkyl group, and R⁴ is hydrogen atom or a lower alkyl group, or a pharmaceutically acceptable salt thereof.

Description: This invention relates to a novel agent for the treatment of kidney diseases, more particularly, to an agent for the treatment of kidney diseases which comprises as an active ingredient a 2-oxo-imidazolidine compound of the formula: wherein R¹ is a lower alkyl group, R² is a lower alkyl group, R³ is a phenyl-substituted lower alkyl group, and R⁴ is hydrogen atom or a lower alkyl group, or a pharmaceutically acceptable salt thereof. It is known that kidney is an important organ which has a function of maintaining the composition of body fluids normally by controlling excretion of water and salts in the body fluids, and that when the renal function is disturbed, it results in decrease in renal blood flow and thereby decrease in excretion of salts, particularly sodium (cf. "Rinsho Yakurigaku Taikei" (Test for Clinical Pharmacology), Vol. 8, Diuretics·Transfusion, pages 54-55, issued by Yamanaka Shoten, 1966). In order to remedy the kidney diseases, it is useful to use a medicament having increasing effects on the renal blood flow and also on the excretion of sodium. The present inventors have intensively studied to obtain a new agent for the treatment of the kidney diseases, and have found that some imidazolidine compounds are effective for increasing renal blood flow and also increasing excretion of sodium and thereby are useful as an agent for the treatment of kidney diseases. An object of the invention is to provide a novel medicament for the treatment of renal failure involving a decrease in renal blood flow. The agent for the treatment of renal failure in accordance with the use of this invention comprises as an active ingredient a 2-oxo-imidazolidine compound of the formula (I) or a pharmaceutically acceptable salt thereof. The active compound includes the compounds of the formula (I) wherein R¹ is an alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl and isobutyl ; R² is an alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl and isobutyl ; R³ is a phenyl-substituted alkyl group having 1 to 4 carbon atoms in the alkyl moiety, such as benzyl, phenethyl, phenylpropyl and phenylbutyl ; and R⁴ is hydrogen atom, or an alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl and isobutyl. Preferred compounds are the compounds of the formula (I) wherein R¹ is methyl, R² is methyl, R³ is phenethyl, and R⁴ is hydrogen atom or ethyl. The compounds (I) of this invention contain three asymmetric carbons within the molecule and hence include four diastereoisomers and eight optical isomers. This invention includes these isomers. Among these isomers, however, the compounds particularly suitable for the intended medical use are the compounds of the formula (I) wherein the carbon atoms at 4-position of the oxoimidazolidine ring and at 2-position of the amino acid moiety of the formula: -NH-CH(R³)COOR⁴ are both S-configuration. Other compounds suitable for the medical use are compounds of the formula (I) wherein the carbon atoms at 4-position of the oxoimidazolidine ring, at 2-position of the alkanoyl moiety of the formula: -COCH(R²)- and at 2-position of the amino acid moiety of the formula: -NH-CH(R³)COOR⁴ are all S-configuration. The 2-oxo-imidazolidine compounds (I) or a pharmaceutically acceptable salt thereof have the effect of increasing the renal blood flow and the excretion of sodium. For instance, when (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-carboxy-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid was intravenously administered to Beagles under anesthesia at a dose of 10 µg/kg, the compound showed remarkable increasing effects on renal blood flow and on excretion of sodium and further on Na/K ratio without substantial increase in excretion of potassium. Likewise, when (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid was administered into the duodenal tract of the animal at a dose of 10 mg/kg, a similar effect was obtained, and the effect was characteristically durable for a long period of time. Moreover, the compounds (I) of this invention have low toxicity. For instance, when (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-carboxy-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid or (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid was orally administered to rats at a dose of 5 g/kg, even after observing for 5 days, no rat was died. The compounds (I) used as an active ingredient in the use of this invention may be used in any form of a free acid (and/or free base) or a pharmaceutically acceptable salt thereof. The free acid (or base) can be converted into its salt by treating it with an organic or inorganic acid or alternatively with an organic or inorganic base in a usual manner. The pharmaceutically acceptable salts of the compounds (I) include organic acid addition salts (e.g. succinate, maleate, fumarate and methanesulfonate), inorganic acid addition salts (e.g. hydrochloride, hydrobromide, sulfate and phosphate), salts with organic bases (e.g. lysine salt and ornithine salt), and salts with inorganic bases (e.g. sodium salt, potassium salt, calcium salt and magnesium salt). The compounds (I) or their pharmaceutically acceptable salts thereof have excellent increasing effects on renal blood flow and on excretion of sodium and hence are useful for the treatment of various kidney diseases, such as edema, acute renal failure, progressive renal failure, productive nephritis in warm-blooded animals including human beings. The pharmaceutical preparations resulting from the use of the invention containing as an active ingredient the compound (I) or a pharmaceutically acceptable salt thereof can be administered by oral route or by parenteral route. The dose of the compound (I) or a pharmaceutically acceptable salt thereof may vary depending on the severity of diseases, age, weight and body conditions of the patients, but is usually in the range of 0.1 to 100 mg/kg/day, preferably 0.5 to 50 mg/kg/day, in case of oral administration, and in the range of 0.001 to 10 mg/kg/day, preferably 0.005 to 5 mg/kg/day, in case of parenteral administration. The compounds (I) or their pharmaceutically accetable salts may be used to form conventional pharmaceutical preparations in admixture with conventional pharmaceutically acceptable carrier or diluent which are usually used for the pharmaceutical preparations suitable for oral or parenteral administration. The pharmaceutically acceptable carrier or diluent includes, for example, starch, lactose, glucose, potassium phosphate, corn starch, gum arabic and magnesium stearate. The pharmaceutical preparations include solid preparations such as tablets, pills, capsules and suppositories, and liquid preparations such as solutions, suspensions and emulsions. These preparations may be sterilized and may optionally contain other additives, such as stabilizers, wetting agents and emulsifiers. The compounds (I) can be prepared by the method as disclosed in European Patent Publication No. 95163 (A2). The pharmacological activities of the compounds of this invention are illustrated by the following experiments. Experiment 1 Male Beagles (weighing 8 - 10.5 kg, 5 dogs per group) fasted for 18 hours were anesthetized with sodium pentobarbital (30 mg/kg, i.v.) and the anesthetized state was maintained by administering continuously the above medicine (4.5 mg/kg/hr, i.v.). The test compound: (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-carboxy-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid sodium salt was intravenously administered to the animals at a dose of 10 µg/kg, and 10 minutes after the administration of test compound, the renal blood flow was measured. Besides, during 20 minutes after the administration of test compound, the urine was collected and the concentration of sodium and potassium in the urine were measured, and the excretion amount of electrolytes and the ratio of Na/K were calculated. The renal blood flow was measured with an electromagnetic flowmeter, the probe of which was placed around the left kidney artery. The results are shown in Table 1. As is clear from the above experimental results, the active compound of this invention showed excellent increasing effects on renal blood flow and on Na/K ratio. Experiment 2 Male Beagles (weighing 8 - 10.5 kg, 5 dogs per group) anesthetized in the same manner as in Experiment 1 were intraduodenally administered the test compound: (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid hydrochloride at a dose of 10 mg/kg, and at an interval of 20 minutes after the administration of test compound, the renal blood flow was measured. Besides, the urine was collected during the above period of time, and the concentrations of sodium and potassium in the urine were measured, and the excretion amount of electrolytes and the ratio of Na/K were calculated. The renal blood flow was measured with an electromagnetic flowmeter, the probe of which was placed around the left kidney artery. The results are shown in Table 2. Before administ. of test compound After adminst. of test compound 20 min. 60 min. 120 min. Renal blood flow (ml/min.) 77 ± 2 85 ± 8 96 ± 8 101 ± 9 Na excretion (µEq/min.) 17 ± 4 33 ± 6 54 ± 12 47 ± 11 K excretion (µEq/min.) 9 ± 1 13 ± 1 13 ± 2 13 ± 2 Na/K ratio 1.98 ± 0.41 2.59 ± 0.33 3.95 ± 0.60 3.47 ±0.52 As is clear from the above experimental results, the active compound of this invention showed durable increasing effects on renal blood flow and on sodium excretion and also on Na/K ratio. The preparations of the present agent are illustrated by the following Examples. Example 1 Tablets: [Formulation]: (Active ingredient) (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid 10 mg Lactose 86.8 mg Polyvinylpyrrolidone 5 mg Corn starch 37 mg Magnesium stearate 1.2 mg Totally 140.0 mg [Method]: To the active ingredient are added lactose and corn starch, and the mixture is well mixed, and thereto is added a solution of polyvinylpyrrolidone in purified water, and the mixture is well kneaded to granulate. The granules thus prepared are dried, and thereto is added magnesium stearate, and the mixture is tabletted in a usual manner to give tablets. Example 2 Tablets: [Formulation]: (Active ingredient) (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-carboxy-3-phenylpropyl)amino]propionyl]-2-oxo-imidazolidine-4-carboxylic acid 10 mg Lactose 80 mg Polyvinylpyrrolidone 3.3 mg Corn starch 35.9 mg Magnesium stearate 0.8 mg Totally 130.0 mg [Method]: In the same manner as described in Example 1, the tablets are prepared. Example 3 Injections: [Formulation]: [Method]: The active ingredient and sodium chloride are dissolved in distilled water for injection, and the solution is filtered with a filter (pore size: 0.22 µm), and filled in ampoules and then sterilized to give injections. Example 4 Injections: [Formulation]: [Method]: Sodium chloride is dissolved in distilled water for injection, and thereto is added the active ingredient, and the mixture is dissolved with sodium hydrogen carbonate. The solution is filtered with a filter (pore size: 0.22 µm). The solution is filled in ampoules and then sterilized to give injections. The pharmaceutical preparation resulting from the use of the present invention may be in unit dose form and each may contain from 5 to 20mg of active ingredient. Furthermore it is to be understood that the invention includes the use of derivatives of the compound of formula (I) which are other than those wherein R⁴ is hydrogen or a lower alkyl group, provided that such derivatives are convertible in the human body to provide the said composition in the free acid form, i.e. when R⁴ is hydrogen. In this specification the term "lower alkyl" includes alkyl groups, which are linear or branched, having up to six or eight carbon atoms.

Claims: The use of a 2-oxo-imidazolidine compound of the formula: wherein R¹ is a linear or branched C₁-C₈ alkyl group, R² is a linear or branched C₁-C₈ alkyl group, R³ is a phenyl-substituted linear or branched C₁-C₈ alkyl group, and R⁴ is hydrogen atom or a linear or branched C₁-C₈ alkyl group, or a pharmaceutically acceptable salt thereof for the production of a pharmaceutical preparation for the treatment of renal failure involving a decrease in renal blood flow. The use according to Claim 1, wherein the compound is 4(S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3-phenylpropyl)amino]-propionyl]-2-oxo-imidazolidine-4-carboxylic acid or a pharmaceutically acceptable salt thereof. The use according to Claim 1, wherein the compound is 4(S)-1-methyl-3-[(2S)-2-[N-((1S)-1-carboxy-3-phenylpropyl)amino]-propionyl]-2-oxo-imidazolidine-4-carboxylic acid or a pharmaceutically acceptable salt thereof. The use according to Claim 1, wherein the compound is a compound of the formula (I) wherein the carbon atoms at 4-position of the oxoimidazolidine ring and at 2-position of the amino acid moiety of the formula: -NH-CH(R³)COOR⁴ are both S-configuration or a pharmaceutically acceptable salt thereof. The use according to Claim 1, wherein the compound is a compound of the formula (I) wherein the carbon atoms at 4-position of the oxoimidazolidine ring, at 2-position of the alkanoyl moiety of the formula: -COCH(R²)- and at 2-position of the amino acid moiety of the formula: -NH-CH(R³)COOR⁴ are all S-configuration or a pharmaceutically acceptable salt thereof. The use as claimed in any one of the preceding claims wherein the preparation is in unit dose form and which contains from 5 to 20mg of the compound of formula I. The use as claimed in Claim 6 wherein the preparation is in the form of a tablet, pill, capsule, suppository or ampoule.

Inventors: KUBO, MASAMI, NISHIYAMA, SHINSUKE, YAMAGUCHI, ISAO
Applicants: TANABE SEIYAKU CO., LTD.
Application year: 1987
Main classification: A61K37
IPC codes: A61K38