| Abstract |
The stereocontrolled synthesis of new sugar derivatives carrying the alpha,beta-unsaturated delta-lactone (butenolide) moiety is described. Sugar-fused or sugar-linked butenolides can be constructed by an efficient reaction sequence involving Wittig olefination of 3- or 5-keto sugars and intramolecular cyclization of the intermediate gamma-hydroxy alpha,beta-unsaturated esters. The antimicrobial activities of the products and that of a known sugar-derived pyranoid alpha,beta-unsaturated delta-lactone were investigated against six pathogenic bacteria and six fungi. The pyranoid alpha,beta-unsaturated delta-lactone 29 proved to be the most active compound in this series towards the plant pathogenic fungi Colletotrichum coffeanum (coffee berry disease) and Pyricularia oryzae (rice blast disease). ((C) Wiley-VCH Verlag GmbH \& Co. KGaA, 69451 Weinheim, Germany, 2008) |
