Bassianolide

Bassianolide, a cyclodepsipeptide insecticide produced by the fungal species B. bassiana and V. lecanii, demonstrates significant biological activity. Upon oral administration, it induces atony in B. mori silkworms at a concentration of 4 ppm and becomes lethal when concentrations exceed 8 ppm. Remarkably, atony in silkworm larvae can also be triggered by doses as low as 2 μg/larva. Further studies reveal that bassianolide (0.01-1 μM) specifically targets muscarinic receptors to inhibit contractions in isolated guinea pig smooth muscle tissue, elicited by acetylcholine, without affecting nicotinic receptor-induced contractions.

CC(C)C[C@@H]1N(C)C(=O)[C@H](OC(=O)[C@H](CC(C)C)N(C)C(=O)[C@H](OC(=O)[C@H](CC(C)C)N(C)C(=O)[C@H](OC(=O)[C@H](CC(C)C)N(C)C(=O)[C@@H](OC1=O)C(C)C)C(C)C)C(C)C)C(C)C