A review is presented of the development of methods for the synthesis of beta-rhamnopyranosides and the related 6-deoxy-beta-mannoheptopyranosides based on the 4,6-O-alkylidene directed synthesis of mannopyranosides and their 6-thia derivatives followed by selective reduction at the 6-position. Applications to total synthesis of complex bacterial oligosaccharides containing the title moieties are presented.