GB871235A - Novel substituted pyrrolidones and salts thereof and a process for the manufacture of same - Google Patents

Abstract

The invention comprises aminoalkyl pyrrolidones of the formula: <FORM:0871235/IV (b)/1> wherein n is zero or a whole number from 1 to 5, R1 and R2 are each hydrogen or alkyl or together with the nitrogen atom form a 5- or 6-membered heterocyclic ring, the valencies shown as broken lines indicating that the alkyl groups are optional substituents, and acid addition salts thereof, and comprises also a process for preparing these compounds wherein a group of the formula -CH2-(CH2)n-NR1R2 is introduced into the nitrogen atom of a 4aryl-pyrrolidone-(2) or a 3- or 4-alkyl or a 3:4dialkyl derivative thereof either by reacting the alkali-metal salt of the pyrrolidone with an aminoalkyl halide R1R2N,(CH2)n,(CH2,Halogen or with a dihalide Halogen,CH2,(CH2)m, CH2,Halogen followed by reaction with an amine HNR1R2, m representing zero or an integer from 1 to 4; or, where a product wherein n is zero is to be made, by reacting the pyrrolidone and the amine HNR1R2 with formaldehyde or a formaldehyde-forming material, and if required converting the product of either of the above processes into a salt by treatment with an acid. Preferably the aryl group in the products is a phenyl group and the alkyl groups are lower alkyl groups such as methyl, ethyl, propyl, butyl and amyl or, in the case where R1 and R2 are joined to form a ring, it may suitably be a piperidine, morpholine or pyrrolidine ring. The compounds are used therapeutically as analgesic and antirheumatic agents, preferred compounds being 1-piperidinopropyl-4-phenyl-4-isopropyl and 1dimethylaminoethyl-4-phenyl-4-propylpyrrolidone-(2). 4-Aryl-pyrrolidone-(2)s used as starting materials such as 1-piperidinopropyl-3-methyl4-phenyl-4-isopropyl-pyrrolidone-(2) are made by reacting an aryl-acetonitrile, e.g. isopropylphenyl-acetonitrile, with an a -halo-alkanoic ester such as ethyl a -bromopropionate and reducing the resulting b -aryl-b -cyano-propionic ester.ALSO:Therapeutic preparations having analgesic and antirheumatic activity, for oral or parenteral administration, comprise a substituted pyrrolidone of the formula <FORM:0871235/VI/1> wherein n represents zero or a whole number from 1 to 5, R1 and R2 each represent hydrogen or alkyl or, together with the nitrogen atom, a 5-or 6-membered ring and the valencies shown as broken lines indicate that the alkyl groups are optional substituents, or an acid addition salt (e.g hydrohalide, sulphate, nitrate, citrate or tartrate) thereof (see Group IV (b)), together with a pharmaceutically acceptable carrier.