Three new toxic pinolidoxins from Ascochyta pinodes

Three new pinolidoxins called epi-, dihydro-, and epoxy-pinolidoxin (2, 4, and 5, respectively) were isolated from Ascochyta pinodes grown on wheat, and their structures were determined using spectroscopic and chemical methods. They were characterized as 7-epi-, 5,6-dihydro-, and 5,6-epoxy-pinolidoxin, respectively. Assayed on pea and bean leaves, epipinolidoxin and dihydropinolidoxin caused necrotic lesions, whereas epoxypinolidoxin was inactive. Only epipinolidoxin and epoxypinolidoxin were active using the brine shrimp assay.