GB728660A - Process for the preparation of amines of the naphthostyril series - Google Patents

Abstract

The invention comprises a process for the preparation of amines of the naphthostyril series characterized in that hydroxy compounds of the general formula <FORM:0728660/IV (b)/1> where Y1 denotes C.OH and Y2 denotes CH or conversely are warmed with amines of the general formula HN.R1R2 where R1 and R2 both denote hydrogen, or R1 and R2 both denote an alkyl group, or R1 denotes hydrogen and R2 denotes an alkyl group or R1 and R2 together denote <FORM:0728660/IV (b)/2> together with their respective neutral sulphurous acid (H2SO3) salts (the term "alkyl" being used to denote methyl, ethyl, propyl or butyl). It also comprises compounds of the formul <FORM:0728660/IV (b)/3> and <FORM:0728660/IV (b)/4> where Y denotes NHCH3 or <FORM:0728660/IV (b)/5> X denotes NH2 and R3 denotes H or CH3. During the course of the reaction the hydroxy group on the ring C is replaced by the corresponding amino group, and the NH group in ring B can also be replaced by NR, where R denotes an alkyl group. In examples (1) 4-amino-naphthostyril is prepared by heating 4-hydroxy-naphthostyrie under pressure with ammonia and ammonium sulphite solution; (2) 5-amino-naphostyril and (3) 4-piperidino-naphthostyril are prepared similarly; (4) 1-methyl-4-methylamino-naphthostyril is obtained by heating 4-hydroxynaphthostyril with methylamine and methyl ammonium sulphite. Acetyl derivatives of the products of example 1, 2 and 4 are prepared.