IMDAV reaction between phenyl-maleic anhydride and thien-yl(fur-yl)allyl-amines: synthesis and mol-ecular structure of (3a,4,4a,7a)-5-oxothieno- and (3a,4,4a,7a)-5-oxofuro[2,3-]iso-indole-4-carb-oxy-lic acids.

The title compounds CHNOS, , and CHNO, , are the products of the IMDAV reaction between phenyl-maleic anhydride and thien-yl(fur-yl)allyl-amines. Their mol-ecular structures comprise fused tricyclic systems containing thio-phene, cyclo-hexene and pyrrolidine rings () or furan, cyclo-hexene and pyrrolidine rings (). The central cyclo-hexene and pyrrolidine rings in both compounds adopt slightly twisted boat and envelope conformations, respectively.