The first total synthesis of gobichelin B: a mixed-ligand siderophore of Streptomyces sp. NRRL F-4415.

The first total synthesis of a structurally diverse mixed ligand siderophore, gobichelin B produced by Streptomyces sp. NRRL F-4415, is reported. The systematic assembly of the building blocks to synthesize Gob-B 1st half and Gob-B 2nd half and subsequent coupling of these two fragments followed by global deprotection using Pearlman's catalyst led to the isolation of gobichelin B in excellent yield and purity.

A one-pot septanoside formation and glycosylation of acyclic dithioacetals derived from 1,2-cyclopropanated sugars.

Ring opening of 3-oxo-1,2-cyclopropanated sugars with thiols leads to the serendipitous discovery of the synthesis of sugar based homologated acyclic dithioacetals. These acyclic dithioacetals were found to undergo one-pot septanoside formation followed by stereoselective glycosylation in the presence of glycosyl acceptors under glycosylation reaction conditions.