| abstract |
The invention comprises 3 : 5-diamino-6-aryl-1 : 2 : 4-triazines of the general formula: <FORM:0759014/IV(a)/1> in which X and Y may be halogen or hydrogen, and a method for preparing them by the conversion of the corresponding 5-hydroxy-3-alkylmercapto-triazine to the 5-chloro-compound and treating this with ammonia. The triazine may be prepared by the action of an arylglyoxylate ester on thiosemicarbazide and alkylating the mercapto group, or by the action of an arylglyoxylate ester on an S-alkylthiosemicarbazide. In examples, the methods described above are used to prepare 3-mercapto - 5 - hydroxy - 6 - phenyl - 1 : 2 : 4-triazine, the corresponding 3-methylthio, and 3 : 5-diamino derivatives, and similar products in which the 6-phenyl group is substituted by 4-Cl-, 2 : 4-dichlor-, 3 : 4-dichlor- and bromine atoms. The Provisional Specification also gives an alternative method of synthesizing the triazine in which aminoguanidine bicarbonate reacts with a methylphenylglyoxylate to give the 3 - amino - 5 - hydroxy - 6 - phenyl1 : 2 : 4 - triazine direct, and refers to products in which X or Y may also be alkoxy, giving as example the preparation of 3-methylthio-5-hydroxy - 6 - (3 : 4 - dimethoxy - phenyl)-1 : 2 : 4 - triazine; 3 - amino - 5 - hydroxy-6 - phenyl - 1 : 2 : 4 - triazine may be obtained by the action of ammonia on the corresponding 3-methylthio-compound; the 3 : 5-dihydroxy-6-phenyl compound may be obtained by acid hydrolysis of the preceding product. |