SE319481

Compounds of the formula where A is substituted or unsubstituted alkyl, cycloalkyl, aryl or heterocyclic, and B is substituted or unsubstituted alkyl, cycloalkyl, aryl or heterocyclic, or OH (and keto forms of the last) are prepared by reacting A-C(NH2)=NOH with RO.CO.B1, where B1 is as B, or is OR to produce B as OH, and R is alkyl, in the presence of an alkali metal alcoholate or an alkaline earth metal alcoholate. Suitable substituents for A and B are NH2, OH, alkoxy, acylamino, alkylamino and dialkylamino, alkyl and halogen (on aromatic radicals) and aryl or heterocyclic (on alkyl radicals). Salts of the compounds may be prepared.