The synthesis of the 2,4,3'-trideoxy and 2,4,3',4'-tetradeoxy analogs of the trimannoside part of the core structure of N-linked glycoproteins, Me 3,6-di-O-a-D-mannopyranosyl-a-D-mannopyranoside, is described. A 2,4-dideoxy (1->6)-linked disaccharide was used as a common intermediate acceptor, which was coupled with a 3-deoxy and a 3,4-dideoxy benzochlorosugar donor, the latter prepd. from Me a-D-mannopyranoside in five steps. Despite the acid-sensitive donors and acceptor, acceptable glycosylation yields were obtained of both the trideoxy- and the tetradeoxy trisaccharide using silver triflate as a promoter (65 and 51%, resp.). Deprotection in one step then gave the target products. [on SciFinder (R)]