Pyridazine Derivatives and Related Compounds Part 5. Pyrazolo[3,4-c]pyridazine: Synthesis and Some Reactions

Abstract

This paper descri.bes the synthesis of three pyrimida[lr ,2' : 1 , 5 ]pyrazolo[3,4-&yfidazin (6,7 and 9) starting from 3-amino[3,4-clpyridazine (1).~yrimidoL5' ,4' :8,6]pyrimido[l' ,2' :1,5]pyrazolo[3,4-clpyridazine derivative (8) was obtained by condensing 7a with formamide.Reactions of 1 with acetic anhydride,~benzoyl chloride, phenacyl bromide and 4-chlorophenacyl bromide gave 3-substituted amino derivatives.