Six new 13-O-acylavermectin B 1 aglycones(3~8) were synthesized from avermectin B1 aglycone and their bioactivities were evaluated against Spodoptera exigua, Spo
A new picrotoxane type sesquiterpene named dendrodensiflorol has been isolated from the stems of Dendrobium densiflorum. Its structure was identified on the bas