GB760944A - Improvements in and relating to pyrimidine derivatives and their manufacture - Google Patents

Abstract

The invention comprises compounds of the formula <FORM:0760944/IV(b)/1> where R is hydrogen or C1-C5 alkyl, R1 is hydrogen or C1-C4 alkyl, R2 is C1-C4 alkyl (or NR1R2 is a piperidino or morpholino group) and Ar is a dihalophenyl group. These are made by reacting HNR1R2 with pyrimidines of the formula <FORM:0760944/IV(b)/2> where X is amino or a group convertible thereto (e.g. acylamino) and Y is chlorine or mercapto. The 4-chloro compounds are prepared by treating the 4-hydroxy compounds with phosphorus oxychloride. The 4-mercapto compounds are obtained by the action of phosphorus pentasulphide on the 4-hydroxy or 5 : 6-dihydro-4-hydroxy compounds. In the examples: (1) 2 : 4-diamino-5-(31 : 41-dichlorophenyl) - 6 - methyl - pyrimidine is heated with sulphuric acid to give the 2-amino-4-hydroxy compound and the latter N-acylated; treatment of the latter successively with phosphorus oxychloride and methylamine yields 2-amino-4-methylamino - 5 - (31 : 41 - dichlorophenyl) - 6-methylpyrimidine; (2) as in (1) using ethylamine giving 2-amino-4-ethylamino-5-(31 : 41-dichlorophenyl) - 6 - methylpyrimidine; (3) 2 - acetamido - 4 - hydroxy - 5 - (31 : 41 - dichlorophenyl) - 6 - ethyl - pyrimidine is prepared by acylation of the product obtained from 2 - amino - 4 - hydroxy - 5 - (31 : 41-dichlorophenyl) - 6 - ethyl - 5 : 6 - dihydropyrimidine and sulphur or from a -(31 : 41-dichlorophenyl) - propionylacetic ester and guanidine; further treatment with phosphorus oxychloride and then with methylamine gives 2 - amino - 4 - methylamino - 5 - (31 : 41 - dichlorophenyl) - 6 - ethylpyrimidine; (4) 2-amino - 4 - mercapto - 5 - (31 : 41 - dichlorophenyl)-pyrimidine is obtained from the 4-hydroxy compound and phosphorus pentasulphide, and converted to the 4-methylamino compound with methylamine and to the 4-dimethylamino compound with dimethylamine.