Therapeutic polyamine-amides

Abstract: A compound of formula I optionally in the form of an acid addition salt in which formula: A represents a substituent which is: hydroxyl, O-alkyl, O-cycloalkyl, O-alkenyl, O-aryl, O-aralkyl, O-carbamate, O-carbonate, O-acyl or halogen a is O-5; the substituents A are identical or different when a is more than 1; B represents a C₁-C₆ aliphatic hydrocarbon group optionally carrying one or more of the substituents: hydroxyl, amino, halogen, C₁-C₄ alkoxy, C₁-C₄ alkyl, aryloxy or carboalkoxy and optionally comprising one or more sites of unsaturatlon and/or one or more carbonyl groups or ketal derivatives thereof; b is O or 1; c, d, f and h, which may be identical or different, are 2, 3, 4, 5 or 6; and i is 0 or 1 D, E and F, which may be identical or different, represent hydrogen or C₁-C₄ alkyl or cycloalkyl, and G and J which may be identical or different represent hydrogen, alkyl or cycloalkyl or G and J together with the nitrogen atom to which they are attached represent a saturated heterocyclic ring system.

Description: This invention relates to polyamine amides of interest for the treatment of cerebral disorders and in particular psychoses, senile dementia, ischaemia, stroke, hypoxia, aneurysm, epilepsy, Parkinson's disease, Alzheimer's disease, Huntington's chorea, and related syndromes and neurological disorders. GB-A- 1 043 345 relates to "phenolic polyamines" (actually polyamine-amides) of the general formula (A) where R₁ represents a divalent open-chain (i.e. either straight or branched) hydrocarbon radical, linking the phenolic nucleus and the terminal carboxyl group and R₂ represents a straight-chain hydrocarbon radical and n is O or 1 and p is O or 1, but when n is 1, p is O. The divalent open-chain hydrocarbon radical represented by R₁ may be saturated or unsaturated, especially a residue of a fatty acid derived from oleic, linoleic or linolenic acid. Such polyamines are co-reactants Tor epoxy resins which impart certain specified properties to the resins. EP-A 353 753, which is a reference cited by virtue of Article 54(3) EPC, relates to compounds of the general formula (B) wherein R₁ and R₂ each is hydrogen atom, an alkyl group or an acyl group, or is a cyclic amino group, m is an integer of 1 to 3, n is an integer of O to 4, x is an integer of 2 to 6 and y is an integer of O to 3, or a salt thereof. Among sub-generic formulae for the amino side-chain is the formula wherein x4 - x6 each is an integer of 2 to 6. Among the possible meanings of the phenolic nucleus are 2-, 3- and 4-hydroxyphenyl. Example 19 discloses 2,4-dihydroxyphenylacetylspermine in the form of a salt. The compounds of EP-A 353 753 are described as useful in elucidation of mechanism of memory and cranial nerve diseases with which glutamic acid is associated and for the prevention of the sequelae of cerebral apoplexy. The present invention provides compounds as defined by Claim 1, with reference to general formula (I), q.v. Typically, when A represents O-alkyl, the alkyl group is C₁-C₄ alkyl. The compounds in which A represents a substituent other than hydroxyl may act through conversion in vivo to the corresponding compound in which the group or groups A are hydroxy groups. The A group, e.g. hydroxyl group, can be at the 2, 3 or 4 position in the ring, preferably the 4 position. A compound of formula (I) which is of particular interest is N-(4-hydroxyphenylacetyl) spermine of formula: Pharmaceutically acceptable acid addition salts of formula (I) include those derived from, for example, the following acids: hydrochloric, hydrobromic, sulphuric, nitric, isethionic, phosphoric, maleic, salicylic, p-toluenesulphonic, tartaric, citric, lactobionic, formic, malonic, pantothenic, succinic, naphthalene-2-sulphonic, benzenesulphonic, methanesulphonic and ethanesulphonic. The preferred salts in terms of pharmaceutical acceptability are the ethanesulphonic acid salts. Such salts may be prepared from the free-base by treatment with the acid suitably in a polar solvent such as water and if necessary with the application of heat. The compounds of the present invention may be readily produced by reacting an acid of formula (II) (in which formula the symbols have the hereinbefore given meanings) or esterifiable derivative thereof, e.g. an acid halide, with an amine or of formula (III) or acid addition salt thereof: (III) NH₂(CH₂)₃NH(CH₂)₄NH(CH₂)₃NH₂. In general , the reaction is conducted in an organic solvent such as 1,2-dimethoxyethane or tetrahydrofuran or dioxan, in the presence of a coupling reagent, such as a carbodiimide e.g. dicyclohexylcarbodiimide or another carbodiimide e.g. 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide-metho-p-toluenesulphonate (morpho CDI, Aldrich), or 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride or methiodide (water soluble reagents, EDC, Aldrich), or 1,3-diisopropylcarbodiimide. The product may be readily purified by chromatography and/or lyophilisation. The acid (or esterifiable derivative) thereof may be benzoic, phenylacetic or phenylpropanoic. The present invention further includes within its scope a composition for the treatment of cerebral disorders, such as psychoses, senile dementia, ischaemia, stroke, hypoxia, aneurysm, epilepsy, Parkinson's disease, Alzheimer's disease, Huntington's chorea, and related syndromes and neurological disorders which comprises a compound of formula I together with a pharmaceutically acceptable diluent or carrier. The compounds of the present invention may be formulated by standard or novel techniques to give, if desired, unit dosage forms. Although the dosage for a particular clinical application must be ascertained by trial, for general guidance appropriate intravenous dosages usually lie in the range 5-500 µg/kg but exceptionally above this i.e. up to 1 mg/kg or, rarely, up to 5 mg/kg. Oral dosages usually lie in the range 1-100 mg/kg. The compound may be administered orally, parenterally (including subcutaneously, intramuscularly and intravenously). The administration will generally be carried out repetitively at intervals, for example once or several times a day. The amount of compounds of formula (I), as hereinbefore defined in accordance with the invention, which is required in order to be effective for treating mammals will, of course, vary and is ultimately at the discretion of the medical or veterinary practitioner treating the mammal in each particular case. The factors to be considered by such a practitioner, e.g. a physician, include the route of administration and pharmaceutical formulation; the mammal's body weight, surface area, age and general condition; and the particular salt to be administered. The invention is illustrated by the following Examples: General procedure for the preparation of monoacyl spermines . To a solution of the required carboxylic acid in an organic solvent such as 1,2-dimethoxyethane or dichloromethane an activating agent e.g. dicyclohexyl carbodiimide was added. The polyamine was introduced in slight excess (two-four fold) in order to increase the yield of the desired monoacylated product. The product was isolated by chromatography over Kieselgel 60 (230-400 mesh). The final product was always soluble in water and was therefore purified by lyophilisation as a final step. Locust Test Method and rationale The compounds were assayed for biological activity on the isolated, retractor unguis nerve-muscle preparation of the locust Schistocerca gregaria (Usherwood, P.N.R and Machili, P. (1968) J. Exp. Biol., 49 : 341.). Isolated muscle preparations were bathed continuously in standard locust saline in a bath of volume 250µl. Twitch tension recordings of the muscle were made to electrical stimulation of its motor innervation supramaximal voltage, frequency 0.1Hz). The locust isolated retractor unguis nerve-muscle is a preparation with well characterised muscle receptors belonging to the quisqualate-sensitive Class (Boden, P. et al ., (1986) Brain Res., 385 : 205.). This preparation has previously been employed to identify antogonists of excitatory amino acid receptors, (e.g. Bateman, A. et al ., (1985) Brain Res., 339 : 237 and Budd, T. et al ., (1988) Brain Res., 448 : 30.). Excitatory amino acid receptors are also believed to be of considerable importance in the mammal and for therapeutic applications. Example 1 N-(2-Hydroxyphenylacetyl)-spermine . To a solution of 2-hydroxyphenylacetic acid (50mg, 0.33mMol) in 1,2-dimethoxyethane (DME) (1ml) was added a solution of dicyclohexyl carbodiimide (71mg, 0.34mMol, 1.05 equivalents) in DME (1ml) in one portion of 25°C. The colourless mixture was allowed to stand at 25°C for 3h during which time a voluminous white precipitate of the urea was formed. This precipitate was then removed by filtration and the residue washed with DME (2 X 1ml). The filtrate and the washings were combined and a solution of spermine (351mg, 1.73mMol, 5.3 equivalents) in DME/dimethylformamide (2ml, 1:1) was added in one portion. The colourless, homogeneous solution was sealed under an atmosphere of nitrogen and allowed to stand at 25°C for 48h. The solution was concentrated in vacuo (water aspirator) and then the residue was applied to a column of silica gel (Kieselgel 60, 230-400 mesh). The product was eluted with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was eluted in fractions 9-14 (10ml fractions) and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f =0.25, chromatogram visualised by inspection under UV light (254nm) and by the production of a pink-purple stain with 0.3% ninhydrin in solution in acidic alcohol. The fractions containing the product were combined and concentrated in vacuo to yield a colourless oil . This oil was dissolved in methanol (2ml), filtered and the solution was then concentrated in vacuo (51mg, 46%). The residue was dissolved in distilled water (2ml) and lyophilised which gave the amide as a colourless, viscous oil (48mg) whose spectroscopic data include: UV max 271 (e max 1 000) and 289sh nm; pmr (90 MHz, ²H₂0) 1.5-1.9 (m, 8H, 4 x C H ₂-CH₂), 2.6-2.9 (m, 10H, 5 x C H ₂-N), 3.25 (t, J = 7, 2H, CON²H-C H ₂-CH₂, 3.55 (s, 2H, Ar-C H ₂-CO), 6.55-6.85 (m, 2H, 2 x Ar H 3,5), and 7.1-7.3 (m, 2H, 2 x Ar H 4,6)ppm; M +1 337 (FAB matrix m -nitrobenzyl alcohol) C₁₈H₃₂N₄O₂ requires M ⁺ 336). The potency of this monoacylated spermine as an antagonist of the complex formed by the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced (1% inhibition) from control (100%) levels at the following concentrations: 3 x 10⁻⁸M 10% inhibition of twitch 3 x 10⁻⁷M 15% 3 x 10⁻⁶M 20% 1.5 x 10⁻⁵M 30% 3 x 10⁻⁵M 30% 1.5 x 10⁻⁴M 85% 3 x 10⁻⁴M 90% The IC₅₀ = 6.2 x 10⁻⁵M Example 2 N-(3-Hydroxyphenylacetyl)-spermine . To a solution of 3-hydroxyphenylacetic acid (50mg, 0.33mMol) in 1,2-dimethoxyethane (DME) (1ml) was added a solution of dicyclohexyl carbodiimide (75mg, 0.36mMol, 1.1 equivalents) in DME (1ml) in one portion of 25°C. The colourless mixture was allowed to stand at 25°C for 3h during which time a voluminous white precipitate of the urea was formed. This precipitate was then removed by filtration and the residue washed with DME (2 X 1ml). The filtrate and the washings were combined and a solution of spermine (167mg, 0.83mMol, 2.5 equivalents) in DME/dimethylformamide (2ml, 1:1) was added in one portion. The colourless, homogeneous solution was sealed under an atmosphere of nitrogen and allowed to stand at 25°C for 24h. The solution was concentrated in vacuo (water aspirator) and then the residue was applied to a column of silica gel (Kieselgel 60, 230-400 mesh). The product was eluted with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was eluted in fractions 12-18 (10ml fractions) and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f =0.18, chromatogram visualised by inspection under UV light (254nm) and by the production of a pink-purple stain with 0.3% ninhydrin in solution in acidic alcohol. The fractions containing the product were combined and concentrated in vacuo to yield a colourless oil . This oil was dissolved in methanol (2ml), filtered and the solution was then concentrated in vacuo (36mg, 33%). The residue was dissolved in distilled water (2ml) and lyophilised which gave the amide as a colourless, viscous oil (30mg) whose spectroscopic data include:- UV max 274sh, 278 (e max 950), and 290sh nm; pmr (90 MHz, ²H₂0) 1.2-2.0 (m, 8H, 4 x C H ₂-CH₂), 2.5-2.9 (m, 10H, 5 x C H ₂-N), 3.3 (t, J =7, 2H, CON²H-C H ₂-CH₂), 3.5 (s, 2H, Ar-C H ₂-CO), 6.45-6.75 (m, 3H, 3 x Ar H 2,4,6), and 7.0-7.3 (m, 1H Ar H 5)ppm: M +1 337 (FAB matrix m -nitrobenzyl alcohol) (C₁₈H₃₂N₄O₂ requires M ⁺ 336). The potency of this monoacylated spermine as an antagonist of the complex formed by the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control (100%) levels at the following concentrations: 3 x 10⁻⁸M 30% 3 x 10⁻⁷M 35% Example 3 N-(4-Hydroxyphenylacetyl)-spermine . To a solution of 4-hydroxyphenylacetic acid (80mg, 0.53mMol) in 1,2-dimethoxyethane (DME) (1ml) was added a solution of dicyclohexyl carbodiimide (120mg, 0.58mMol, 1.1 equivalents) in DME (1ml) in one portion at 25°C. The colourless mixture was allowed to stand at 250°C for 3 h during which time a voluminous white precipitate of the urea was formed. This precipitate was then removed by filtration and the residue washed with DME (2 X 1ml). The filtrate and the washings were combined and a solution of spermine (600mg, 2.97mMol, 5.6 equivalents) in DME/dimethylformamide (2ml, 1:1) was added in one portion. The colourless, homogeneous solution was sealed under an atmosphere of nitrogen and allowed to stand at 25°C for 48h. The solution was concentrated in vacuo (water spirator) and then the residue was applied to a column of silica gel (Kieselgel 60, 230-400 mesh). The product was eluted with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was eluted in fractions 8-13 (10ml fractions) and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f =0.17, chromatogram visualised by inspection under UV light (254nm) and by the production of a pink-purple stain with 0.3% ninhydrin in solution in acidic alcohol. The fractions containing the product were combined and concentrated in vacuo to yield a colourless oil . This oil was dissolved in methanol (2ml), filtered and the solution was then concentrated in vacuo (65mg, 37%). The residue was dissolved in distilled water (2ml) and lyophilised which gave the amide as a colourless, viscous oil (57mg) whose spectroscopic data include:- UV max 220 (e max 6 000) and 270 (e max 1 300) nm: pmr (90 MHz, ²H₂0) 1.2-2.0 (m, 8H, 4 x CH₂-C H ₂-CH₂), 2.5-2.9 (m, 10H, 5 x C H ₂-N), 3.2 (t, J =7, 2H, CON²H-C H ₂-CH₂), 3.4 (s, 2H, Ar-C H ₂-CO), 6.7 (d, J =8, 2H, 2 x Ar H 3,5), and 7.1 (d, J = 8, 2H, 2 x Ar H 2,6)ppm: M +1 337 (FAB matrix m-nitrobenzyl alcohol) (C₁₈H₃₂N₄O₂ requires M + 336). The potency of this monoacylated spermine as an antagonist of the complex formed by the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control (100%) levels at the following concentrations: 5.9 x 10⁻⁷M 9% 5.9 x 10⁻⁶M 25% 2.95x 10⁻⁵M 74% 4.43x 10⁻⁵M 91% 5.9 x 10⁻⁵M 96% The IC₅₀ = 8.7 x 10⁻⁶M Example 4 N -(2- Hydroxyphenylpropanoyl )- spermine .-To a solution of 2-hydroxyphenylpropanoic acid (61 mg, 0.37 mMol) in 1,2-dimethoxyethane (DME) (1 ml) was added a solution of dicyclohexylcarbodiimide (76 mg, 0.37 mMol) in DME (1 ml) in one portion at 25°C. The colourless mixture was allowed to stand at 25°C for 3 h during which time a voluminous white precipitate of the urea was formed. This precipitate was then removed by filtration and the residue washed with DME (2 x 1 ml). The filtrate and the washings were combined and a solution of spermine (300 mg, 1.48 mMol, 4.0 equivalents) in DME/dimethylformamide (2 ml, 1:1) was added in one portion. The colourless, homogeneous solution was sealed under an atmosphere of nitrogen and allowed to stand at 25°C for 48 h. The solution was concentrated in vacuo (water aspirator) and the residue was then applied to a column of silica gel (Kieselgel 60, 230-400 mesh). The product was eluted with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was eluted in fractions 7-11 (10 ml fractions) and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f = 0.33, chromatogram visualised by inspection under UV light (254 nm) and by the production of a pink-purple stain with 0.3% ninhydrin in solution in acidic alcohol. The fractions containing the product were combined and concentrated in vacuo to yield a colourless oil. This oil was dissolved in methanol (2 ml), filtered and the solution was then concentrated in vacuo (112 mg, 87%). The residue was dissolved in distilled water (2 ml) and lyophilised which gave the amide as a colourless, viscous oil (82 mg) whose spectroscopic data include: pmr (90 MHz, ²H₂0) 1.3-2.1 (m, 8H, 4 x C H ₂-CH₂), 2.5-3.1 (m, 14H, 5 x C H ₂-N and Ar-C H ₂-C H ₂), 3.3 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 6.7-7.0 (m, 2H, 2 x Ar H 3,5), and 7.1-7.4 (m, 2H, 2 x Ar H 4,6)ppm. The potency of this monoacylated spermine as an antagonist of the complex formed by the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrcically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control levels between the following concentrations: 1 x 10⁻⁵M and 9 x 10⁻⁵M, such that an approximately 50% reduction was obtained at 5 x 10⁻⁵M. Example 5 N -(3- Hydroxyphenylpropanoyl )- spermine .-To a solution of 3-hydroxyphenylpropanoic acid (167 mg, 1.01 mMol) in dichloromethane (5 ml) was added dicyclohexylcarbodiimide (226 mg, 1.10 mMol, 1.1 equivalents) in one portion at 25°C. The colourless mixture was allowed to stand at 25°C for 2 h during which time a voluminous white precipitate of the urea was formed. This precipitate was then removed by filtration and the residue washed with dichloromethane (1 ml). The filtrate and the washings were combined and spermine (400 mg, 1.98 mMol, 1.96 equivalents) was added in one portion. The colourless, homogeneous solution was sealed under an atmosphere of nitrogen and allowed to stand at 25°C for 4 h. The solution was concentrated in vacuo (water aspirator) and the residue was then applied to a column of silica gel (Kieselgel 60, 230-400 mesh). The product was eluted with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was eluted in fractions 13-19 (10 ml fractions) and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f = 0.11, chromatogram visualised by inspection under UV light (254 nm) and by the production of a pink-purple stain with 0.3% ninhydrin in solution in acidic alcohol. The fractions containing the product were combined and concentrated in vacuo to yield a colourless oil. This oil was dissolved in methanol (2 ml), filtered and the solution was then concentrated in vacuo (105 mg, 30%). The residue was dissolved in distilled water (2 ml) and lyophilised which gave the amide as a colourless glass (80 mg) whose spectroscopic data include: UV max 217 (e max 2 500) and 272 (e max 1 200)nm; pmr (90 MHz, ²H₂0) 1.5-2.0 (m, 8H, 4 x C H ₂-CH₂), 2.4-3.0 (m, 14H, 5 x C H ₂-N and Ar-C H ₂-C H ₂), 3.2 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 6.55-6.75 (m, 3H, 3 x Ar H 2,4,6), and 7.05-7.3 (m, H Ar H 5)ppm; M +1 351 (FAB matrix m-nitrobenzyl alcohol) C₁₉H₃₄N₄0₂ requires M ⁺ 350). The potency of this monoacylated spermine as an antagonist of the complex formed by the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control (100%) levels at the following concentrations: 1.08 x 10⁻⁷M 10% inhibition of twitch 1.08 x 10⁻⁶M 15% Examples 6-10 In the following Examples, compounds of formula (I) were prepared by following the above General Procedure and adapting the methods described in the preceding Examples. The compounds prepared together with an indication of their potency as L-glutamate antagonists when tested in the locust leg retractor muscle pharmacological screen follow: Example 6 N -2- Hydroxybenzoyl )- spermine .-According to the General Procedure using 2-hydroxybenzoic acid (138 mg, 1.00 mMol), dicyclohexylcarbodiimide (226 mg, 1.10 mMol), and spermine (400 mg, 1.98 mMol) in dichloromethane (6 ml), activation during 3 h and coupling over 4 h. The product was eluted over silica gel with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was in fractions 8-15 and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f = 0.23, (98 mg, 29%), lyophilisation gave 64 mg of a colourless, viscous oil whose spectroscopic data include: pmr (90 MHz, ²H₂0) 1.5-1.9 (m, 8H, 4 x C H ₂-CH₂, 2.6-2.9 (m, 10H, 5 x C H ₂-N), 3.25 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 6.55-6.85 (m, 2H, 2 x Ar H 3,5), and 7.1-7.3 (m, 2H, 2 x Ar H 4,6)ppm; M +1 323 (FAB matrix m -nitrobenzyl alcohol and sodium chloride) C₁₇H₃₀N₄0₂ requires M ⁺ 322). The potency of this monoacylated spermine as an antagonist of the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control level at 1.09 x 10⁻⁵M by approximately 25%. Example 7 N -(3- Hydroxybenzoyl )- spermine .-According to the General Procedure using 3-hydroxybenzoic acid (138 mg, 1.00 mMol), dicyclohexylcarbodiimide (226 mg, 1.10 mMol), and spermine (400 mg, 1.98 mMol) in dichloromethane (6 ml), activation during 3 h and coupling over 17 h. The product was eluted over silica gel with dichloromethane/methanol/0.880 ammonia solution (4:2:1). The desired amide was in fractions 8-13 and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 4:2:1), R f = 0.29, (76 mg, 24%), lyophilisation gave 52 mg of a colourless, viscous oil whose spectroscopic data include: pmr (90 MHz, ²H₂0) 1.4-1.9 (m, 8H, 4 x C H ₂-CH₂), 2.5-2.9 (m, 10H, 5 x C H ₂-N), 3.25 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 6.5-6.8 (m, 3H, 3 x Ar H 2,4,6), and 7.0-7.3 (m, 1H Ar H 5)ppm; M +1 323 (FAB matrix m -nitrobenzyl alcohol and sodium chloride) C₁₇H₃₀N₄0₂ requires M ⁺ 322). The potency of this monoacylated spermine as an antagonist invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control levels at 1.02 x 10⁻⁵M by approximately 40%. Example 8 N -(4- Hydroxybenzoyl )- spermine .-According to the General Procedure using 4-hydroxybenzoic acid (80 mg, 0.58 mMol), dicyclohexylcarbodiimide (125 mg, 0.61 mMol), and spermine (430 mg, 2.13 mMol) in DME/DMF (4 ml, 3:1), activation during 3 h and coupling over 48 h. The product was eluted over silica gel with dichloromethane/methanol/0.880 ammonia solution (2:2:1). The desired amide was in fractions 8-12 and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH, 2:2:1), R f = 0.29, (23 mg, 12%), lyophilisation gave 7 mg of a colourless, viscous oil whose spectroscopic data include: pmr (90 MHz, ²H₂0) 1.4-1.9 (m, 8H, 4 x C H ₂-CH₂), 2.5-2.9 (m, 10H, 5 x C H ₂-N), 3.25 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 6.6-6.9 (m, 2H, 2 x Ar H 3,5), and 7.0-7.3 (m, 2H, 2 x Ar H 2,6)ppm; M +1 323 (FAB matrix m -nitrobenzyl alcohol) C₁₇H₃₀N₄0₂ requires M ⁺ 322). The potency of this monoacylated spermine as an antagonist of the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control levels: between 10⁻⁵M and 10⁻⁴M such that an approximately 50% reduction was obtained at 5 x 10⁻⁵M. Example 9 N -(2- Methoxyphenylacetyl )- spermine .-According to the General Procedure using 2-methoxyphenylacetic acid (81 mg. 0.49 mMol), dicyclohexylcarbodiimide (53 mg, 0.26 mMol), and spermine (201 mg, 0.99 mMol) in DME (4 ml), activation during 2.5 h and coupling over 48 h. The produce was eluted over silica gel with the lower layer of dichloromethane/methanol/0.880 ammonia solution (2:1:1). The desired amide was in fractions 6-10 and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH lower layer, 2:1:1), R f = 0.25, (28 mg, 31%), lyophilisation gave 16 mg of a colourless, viscous oil whose spectroscopic data include: pmr (90 MHz, ²H₂0) 1.35-1.85 (m, 8H, 4 x C H ₂-CH₂), 2.4-2.9 (m, 10H, 5 x C H ₂-N), 3.25 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 3.5 (s, 2H, Ar-C H ₂-CO), 3.83(s, 3H, 0C H ₃), 6.75-7.05 (m, 2H, 2 x Ar H 3,5), and 7.15-7.35 (m, 2H, 2 x Ar H 4,6)ppm. The potency of this monoacylated spermine as a non-competitive antagonist of the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control (100%) levels between 1 x 10⁻⁴M and 1 x 10⁻³M, such that an approximately 50% reduction was obtained at 5 x 10⁻⁴M. Example 10 N -(4- Methoxyphenylacetyl )- spermine .-According to the General Procedure using 4-methoxyphenylacetic acid (83 mg, 0.50 mMol), dicyclohexylcarbodiimide (56 mg, 0.27 mMol), and spermine (201 mg, 0.99 mMol) in DME (4 ml), activation during 2.5 h and coupling over 48 h. The product was eluted over silica gel with the lower layer of dichloromethane/methanol/0.880 ammonia solution (4:1:1). The desired amide was in fractions 16-25 and was homogeneous when monitored by tlc on silica (CH₂Cl₂/MeOH/NH₄OH lower layer, 4:1:1), R f = 0.07, (30 mg, 32%), lyophilisation gave 21 mg of a colourless, viscous oil whose spectroscopic data include: pmr (90 MHz, H₂0) 1.4-1.8 (m, 8H, 4 x C H ₂-CH₂), 2.4-2.9 (m, 10H, 5 x C H ₂-N), 3.3 (t, J = 7, 2H, CON²H-C H ₂-CH₂), 3.5 (s, 2H, Ar-C H ₂-CO), 3.83(s, 3H, OC H ₃), 6.8-6.95 (m, 2H, 2 x Ar H 3,5), and 7.1-7.3 (m, 2H, 2 x Ar H 2,6)ppm. The potency of this monoacylated spermine as an antagonist of the invertebrate L-quisqualate sub-type L-glutamate receptor and its ion channel was assayed using the electrically stimulated retractor unguis muscle of the locust (Schistocerca gregaria). Twitch amplitude was reduced from control (100%) levels between 1 x 10⁻⁴M and 1 x 10⁻³M, such that an approximately 50% reduction was obtained at 5 x 10⁻⁴M. EVALUATION ON A MAMMALIAN NEURONAL PREPARATION Method Coronal slices of cerebral cortex were cut with a Vibratome from the brains of freshly killed Wistar rats. Wedges of tissue were cut from either side of the mid-line to include the cortex and corpus callosum. The wedges were mounted in a grease-gap apparatus such that the cortex protruded into one compartment and the corpus callosum into the other compartment of a two-compartment bath, (Harrison N.L. & Simmonds M.A. (1985), Br. J. Pharmacol 84 : 381-391.). Each compartment could be separately perfused with Krebs bicarbonate medium pre-gassed with 95% 0₂/5% CO₂ at room temperature. The volume of each compartment was 1.8 ml and the perfusion rate was 2 ml/min. The compartment containing the cortical part of the wedge was also gassed directly so that drugs could be injected into the bath with the perfusion pump stopped. This variant on the published method was adopted to minimise the amount of drug required. The potential difference between the two compartments was recorded continuously via Ag/AgCl electrodes. The polyamine compounds were tested for their ability to antagonise either the quisqualate receptor agonist (RS)-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) (Tocris Neuramin) or the NMDA receptor agonist N-methyl-D-aspartate (Sigma). The polyamine compounds were supplied as freeze-dried aliquots and, for each experiment, one of these was dissolved in sufficient distilled water to produce a 10mM stock solution. To permit optimal responses to NMDA, Mg²⁺ was omitted from the medium. Since this generally results in epileptiform discharges in the wedges, (Horne A.L, Harrison N.L, Turner J.P. and Simmonds M.A. (1986) Eur. J. Pharmacol 122 : 231-238) tetrodotoxin (Sigma) was used to suppress such activity and was initially added to the bath to a concentration of 2.5 µM for 5 min. and thereafter was incorporated into the perfusion medium at a concentration of 0.1 µM. The experimental protocol was to perfuse the tissue initially to obtain a steady baseline. The perfusion was then stopped and an aliquot of a 1 mM stock solution of either AMPA or NMDA was injected into the cortical compartment to give a concentration of 2.5 or 5 µM. Once the depolarisation response had reached its peak (usually within 3 min.), the perfusion was resumed to wash out the drug and return the potential to baseline. This procedure was repeated 3 or 4 times to achieve consistent responses. With the perfusion again stopped, the polyamine was injected into the cortical compartment to a concentration of 1, 10 or 100 µM, using stock solutions of 0.1, 1 or 10 mM, respectively. After 20 min, a dose of AMPA or NMDA was injected, as before, followed by the resumption of perfusion after the peak of the response. Repeated injections of AMPA or NMDA were made without further addition of the polyamine. In control experiments, no polyamine was injected. Compound of Example 3 The potency of N-(4-hydroxyphenylacetyl) spermine was tested as an antagonist of NMDA- and AMPA- induced response in a rat brain slice model. Electrophysiologically recorded depolarisation responses were reduced from control levels (% inhibition) at the following concentrations: AMPA NMDA 10⁻⁶M 0% 29% 10⁻⁵M 22% 35%

Claims: Compounds of the general formula: wherein: A represents a hydroxyl, O-alkyl or O-C₇₋₁₀ phenalkyl substituent and b is 0,1 or 2, in the form of the free bases or their pharmaceutically acceptable acid addition salts. Compounds according to Claim 1 wherein A represents a 4-position substituent. Each of the compounds: and their pharmaceutically acceptable acid addition salts. Compounds according to Claim 1,2 or 3, for use in the treatment of cerebral disorders. Compounds according to Claim 1,2 or 3, for use in the treatment of a patient suffering from a stroke. A pharmaceutical composition comprising a compound claimed in Claim 1,2 or 3, together with a pharmaceutically acceptable diluent or carrier.

Inventors: BLAGBROUGH IAN STUART, BYCROFT BARRIE WALSHAM, MATHER ALAN JOHN, USHERWOOD PETER NORMAN RUSSELL, BLAGBROUGH, IAN STUART, BYCROFT, BARRIE WALSHAM, MATHER, ALAN JOHN, USHERWOOD, PETER NORMAN RUSSELL
Applicants: BRITISH TECH GROUP, BRITISH TECHNOLOGY GROUP LIMITED
Application year: 1989
Main classification: C07C235
IPC codes: A61K31, C07C235, A61P25, A61P9