Methyl 2-deoxy-2-[(1S)-2.5-dideoxy-2.5-imino-L-ribitol-1-C-yl)-alpha-D-glucopyr anoside ((+)-6) was obtained from the product of Nozaki-Kishi coupling of 2,5-{[(tert-butoxy)carbonyl]imino}-2,5-dideoxy-3,4-O-isopropl-idene-L-ri bose ((-)-9) and 4-0-benzyl-6-O-[(benzyloxy)methyl]-3-deoxy-2-O-[(trifluoromethyl)sulfony l]-alpha-D-erythro-hex-2-enopyranosicle ((+)-12). The alkenyl triflato (+)-12 was derived from levoglucosenone (1).