Synthetic route towards (5R,2′S,5′S,6′S)-ribosyl-diazepanone,an analogue core of the liposidomycins

The synthesis of (5R,2′S,5′S,6′S)-ribosyl-diazepanone, an analogue core of liposidomycins is described. The core ribosyl seven-membered heterocycle of nucleoside antibiotic liposidomycins was formed by reductive amination of an α-ribosylamino ester derived from d-ribose, and an amino aldehyde derived from methyl 4-triisopropylsilyloxy-3-oxobutanoate, followed by a peptidic coupling reaction.