3-Alkoxy-2-cyano-N-formyl-acrylamides prepn. - by reacting cyanoacetamide with trialkylorthoformate or dialkoxymethyl carboxylate

摘要

3-Alkoxy-2-cyano-N-formyl-acrylamides of the formula O=CH-NH-CO-C(CN)=CH-Or (I) (where R is 1-7, pref. 1-4C alkyl, esp. ethyl) are prepd. by reacting cyanoacetamide with a trialkyl orthoformate Hc(OR)3 (II) or a dialkoxymethyl carboxylate R'COOCH(OR)2 (III) (where R' is an organic residue such as aryl, aralkyl, cycloalkyl or, pref. 1-7C alkyl or H) in the presence of an acid anhydride and hydrolysing the reaction product. (I; R = Et) is an inter for pyrazolo (3,4-d) pyrimidines, esp. 4-hydroxy-1H-pyrazolo (3,4-d)pyrimidine (allopurinol), a known agent for the treatment of gout.