A convergent synthetic approach to the nucleoside-type liposidomycin antibiotics.

[reaction: see text] A synthetic approach toward the liposidomycins, a family of complex nucleoside-type antibiotics, is reported based on the synthesis of epoxy-amides derived from the reaction of sulfur ylides with the uridyl aldehyde derivative 6. To this end, the epoxy-amide derivative of indoline 14 was stereoselectively prepared and, after treatment with DDQ, transformed into the corresponding N-indole epoxyamide 15. The indole 15 provides ready access to a variety of structures related to the diazepanone core present in the liposidomycins by reaction with a variety of amines.