Microbially Aided Synthesis of Carbohydrates

Abstract

The (2S,3R) methyldiols (4), generated in a multienzymatic process in fermenting baker's yeast from α-position unsaturated aromatic aldehydes, are used as starting materials in the synthesis of deoxy- and deoxy aminosugars of the L-series, including the L-daunosamine and L--vancosamine derivatives 17 and 34. Our interest in the synthesis of deoxy- and deoxy-amino sugars of the L-series originates from studies (1) on the products obtained by the action of fermenting baker's yeasts on such aromatic, α, β -unsaturated aldehydes as cinnamaldehyde (1a) and α-methylcinnamaldehyde (1b ). The transformation proceeds as indicated in Eq. 1. While the production of 2 and 3 from 1 falls amongst the known capacities of baker's yeast, the formation, in yields of 20-25 % of 4, containing two additional carbon atoms with respect to the precursor aldehyde and two adjacent chiral centres of the type R2 R1 CHOH, is new and quite fruitful from the synthetic