Patent GB-592935-A (GB)
Title: New pyrimidine compounds
IPC: C07D239/52
Filed: 1944-04-11
Abstract: Pyrimidine compounds of the general formula <FORM:0592935/IV/1> wherein X represents hydrogen or a hydrocarbon radical and Y represents a neutral substituent, e.g. a hydrocarbon radical, a halogen atom, an alkoxy, aryloxy or arylmercapto group or a cyano group, and also X and Y may be joined together to form an alkylene chain, and An represents an anilino group which bears one or more non-acidic nuclear substituents such as hydrocarbon radicals (which may themselves be substituted and which may be attached to the anilino group directly or indirectly, e.g. through an oxygen, sulphur or nitrogen atom or through a carboxyl group or may have two carbon atoms in common with the anilino radical as in the case of a naphthylamine group), halogen atoms and nitro, cyano or esterified carboxyl groups, are made by the interaction of the appropriately substituted aniline with a 2-alkylmercapto-4-hydroxypyrimidine bearing in the 5- and 6-positions respectively the atoms or groups Y and X.  Reaction is effected by heating the reagents, optionally in presence of a solvent or diluent, b -ethoxyethanol being specified. In the examples, 2-methylmercapto-4-hydroxy-5-bromo-6-methylpyrimidine and p-chloroaniline yield 2 - p - chloroanilino - 4 - hydroxy - 5 - bromo- 6 - methylpyrimidine, 2-ethylmercapto-4-hydroxy - 5 - phenylpyrimidine and p - chloroaniline or p - anisidine yield 2-p-chloroanilino- or -anisidino-4-hydroxy - 5 - phenylpyrimidine, 2 - methylmer - capto - 4 - hydroxy - 5 - methylpyrimidine and p - chloroaniline yield 2-p-chloroanilino-4-hydroxy-5 - methylpyrimidine, 2 - ethylmercapto - 4 - hydroxy-5 : 6-dimethylpyrimidine and p-chloroaniline yield 2-p-chloroanilino-4-hydroxy-5 : 6-dimethylpyrimidine, 2 - methylmercapto - 4 - hydroxy - 5 - ethyl - 6 - methylpyrimidine and p - chloroaniline yield 2-p-chloroanilino-4-hydroxy-5-ethyl-6-methylpyrimidine, 2-ethylmercapto-4-hydroxy-5-phenoxypyrimidine and p-chloroaniline yield 2 - p - chloroanilino - 4 - hydroxy- 5 - phenoxypyrimidine, 2 - ethylmercapto - 4 - hydroxy - 5 - benzyl - 6 - methylpyrimidine and p-chloroaniline yield 2-p-chloroanilino-4-hydroxy-5 - benzyl - 6 - methylpyrimidine, 2 - methylmercapto-4-hydroxy-5 : 6 : 7 : 8-tetrahydroquinazoline and p-chloroaniline yield 2-p-chloroanilino-4-hydroxy-5 : 6 : 7 : 8-tetrahydroquinazoline and 2 - methylmercapto - 4 - hydroxy - 5 : 6 - trimethylenepyrimidine and p-chloroaniline yield 2-p-chloroanilino-4-hydroxy-5 : 6-trimethylene-pyrimidine.  Other amines specified are p-nitro-, -bromo- and -cyano-anilines, m- and o-chloroanilines, b -naphthylamine and 6-bromo-and -methoxy-2-naphthylamines. Specification 592,928 is referred to.  Alkylmercapto - hydroxy - pyrimidines used as starting materials may be made by interaction of alkyl isothioureas with formylacetic esters bearing a group, Y, on the a -carbon atom and, where necessary, a hydrocarbon radical on the b -carbon atom.  Thus, 2-methylmercapto-4-hydroxy - 5 : 6 - trimethylenepyrimidine is obtained from cyclopentanone-a -carboxylic ester and S-methyl-isothiourea.  Some are made by appropriate subsequent treatment of compounds so made; thus, 2-methylmercapto-4-hydroxy-5 - bromo - 6 - methylpyrimidine is made by bromination of 2-methylmercapto-4-hydroxy-6-methylpyrimidine, itself made from methylisothiourea and acetoacetic ester, and 2-methylmercapto - 4 - hydroxy - 5 : 6 : 7 : 8 - tetrahydroquinazoline is made by methylation of the corresponding 2-mercapto compound, obtained from thiourea and cyclohexanone-a -carboxylic ester.