Verfahren zur Herstellung von Imidazolderivaten

摘要

1,051,388. Imidazoles. F. HOFFMANN-LA ROCHE & CO. A.G. Nov. 12, 1965 [Nov. 17, 1964 (2)], No. 48051/65. Heading C2C. Imidazoles of the formula and their salts with pharmaceutically acceptable strong bases, wherein R1, R2 and R3 each represent a C 1-7 -alkyl group or R1 and R2 together represent a group of the formula in which R4 and R5 each represent H or C 1-7 alkyl and broken lines denote that the groups attached are optional and wherein R3 is absent in the salts with strong bases, are prepared by reacting an amino compound of the formula or an acid addition salt thereof with an alkali metal nitrite in an aqueous reaction medium having a pH of less than about 8 and, if desired, treating any reaction product in which R3 is absent and R1 and R2 together represent a group of the formula with an alkylating agent to introduce R3 or converting any reaction product in which R3 is absent with a pharmaceutically acceptable strong base. 2-Amino-imidazole sulphate is prepared by reducing 2 - (4 - bromobenzeneazo) - imidazole or by reacting amino-acetaldehyde diethyl acetal with methyl isourea sulphate and cyclizing the N-(2,2-diethoxy-ethyl).guanidine sulphate so formed. 2-Amino-4-methyl imidazole sulphate is similarly prepared. Pharmaceutical compositions comprise compounds of the first general formula above wherein R1 is present and R2, R3, R4 and R5 are as defined and salts thereof, when R3 is absent, with strong bases, and a carrier therefor. The compositions, which are useful in the treatment of pathogenic yeast and protozoal infections, may be in forms for enteral, parenteral or topical administration. The compositions may contain other therapeutically active substances.