Three general methods are described for the synthesis of 2, 4-bis-(alkylainino)-6, 7- diphenylpteridines(I), of interest because of their possible biological activity. Method A involves the reaction between an alkylamine and 4-amino-2-mercapto-6, 7- diphenylpteridine (11); Method B, the reaction between an alkylamine and 2, 4-dichloro-6, 7- diphenylpteridine(111); and Method C, the reaction between an alkylamine and 2, 4- ...