Collect. Czech. Chem. Commun. 1983, 48, 1878-1884

The synthesis and reactions of arylfurocondensed derivatives

Alžbeta Krutošíková, Jaroslav Kováč and Eva Kraľovičová

Department of Organic Chemistry, Slovak Institute of Technology, 812 37 Bratislava


The preparation of new 9-arylfuro[2',3':4,5]pyrrolo[1,2-d]-1,2,4-triazolo[3,4-f]-1,2,4-triazines (V) and 7-aryl-1,4-dioxo-1,2,3,4-tetrahydrofuro[2',3':4,5]pyrrolo[1,2-d]-1,2,4-triazines (VII) from 2-aryl-4H-furo[3,2-b]pyrrole-5-carbohydrazides (I) is described. Reaction of I with triethyl orthoformate or acetate afforded 7-aryl-1,2-dihydrofuro[2',3':4,5]pyrrolo[1,2-d]-1,2,4-triazin-1-ones, or their 4-methyl analogues II giving with phosphorus pentasulfide thiones III, reacting with hydrazine to the corresponding hydrazides IV. Cyclization of IV with orthoformates, or orthoacetates led to V. Methylchloro formate reacted with I to yield N-methoxycarbonyl-2-aryl-4H-furo[3,2-b]pyrrole-5-carbohydrazides VI undergoing cyclization in an alkaline medium to VII.