The first total synthesis of caminoside B, a novel marine antimicrobial glycolipid isolated from the marine sponge Caminus sphaeroconia, was developed. This marine small molecule inhibitor (IC(50) = 20 mu M) targeting type III secretory pathway of bacterial pathogenesis was assembled in good yield via a '2+2+1' strategy based on stereocontrolled construction of the four glycosidic linkages. (C) 2010 Elsevier Ltd. All rights reserved.