ANTIINSECTAN ALKALOIDS - SHEARININES-A-C AND A NEW PAXILLINE DERIVATIVE FROM THE ASCOSTROMATA OF EUPENICILLIUM-SHEARII

Four new antiinsectan indole alkaloids (1-4) have been isolated from o rganic extracts of the sclerotioid ascostromata of Eupenicillium shear ii (NRRL 3324). These extracts also afforded five known, related metab olites (5-9). The structures of the new compounds were determined thro ugh analysis of H-1 NMR, C-13 NMR, HMQC, and HMBC experiments. Compoun ds 1-9 were isolated from fractions displaying activity in dietary ass ays against the corn earworm Helicoverpa zea and the dried-fruit beetl e Carpophilus hemipterus, and most of the compounds show potent activi ty in these assays. Shearinine A (1) also exhibited activity in a topi cal assay against H. zea, and shearinine B (2) caused significant mort ality in a leaf disk assay against the fall armyworm Spodoptera frugip erda.