Chiral synthesis of polyketide-derived natural products. Part 5. Synthesis of a chiral segment corresponding to the C-1—C-5 unit of erythromycin A from D-glucose

Abstract

As a right-hand segment with three consecutive chiral centres corresponding to the C-1—C-5 unit of erythromycin A (1), (2S,3R,4S)-3,5-isopropylidenedioxy-2,4-dimethylpentanal (32) was synthesized from D-glucose (5) by application of MPM (4-methoxybenzyl) protection for an hydroxy function and some fairly stereoselective reactions, hydroboration and hydrogenation.