C-glucosyl, mannosyl and galactosyl 2-iodopropane, readily obtained from the corresponding C-glycosyl ketones, were coupled with (+)- or (-)-camphorsultam glyoxylic oxime ether with diastereoselectivity ranging from 70:30 to 80:20. C-glucosyl allothreonine was obtained by cleavage of the camphorsultam moiety.