PUTAMINOXIN-D AND PUTAMINOXIN-E FROM PHOMA-PUTAMINUM

Two 10-macrolides, named putaminoxins D and E, were isolated together with other recently identified toxic putaminoxins from culture filtrat es of Pl?oma putaminum, the causal agent of leaf necrosis of Erigeron annuus, a common weed found in fields and pastures. Putaminoxins D and E were characterized by spectroscopic and chemical methods as a new d isubstituted nonen- and nonanolide, respectively. Moreover, 5-O-formyl putaminoxin was isolated as an artefact from the culture filtrates aci dified with formic acid. When they were assayed on leaves of host and non-host plants, putaminoxins D and E and 5-O-formylputaminoxin showed no toxicity, unlike other putaminoxins. (C) 1998 Published by Elsevie r Science Ltd. All rights reserved.