The formation of C-alkyl derivatives from 1,6:2,3-dianhydro-manno-pyranose precursors has been examined. Regioselectivity at C2 is excellent when the C4 substituent is benzyloxy. However, with CH3, reaction at C2 and C3 occurs, although the ratio of products can be altered substantially depending on the nature of the nucleophile and the reaction conditions.