By utilizing L-serine, both enantiomers of all trans a-hydroxymethyl 3-hydroxy-4-nitro-pyrrolidine were efficiently prepared through tandem Michael-Henry methodology. Their stereochemistry has been assigned through conversion of one of them to trans 2-hydroxymethyl-3-hydroxypyrrolidine, a naturally occurring compound recently isolated from Castanospermum australe. Copyright (C) 1996 Elsevier Science Ltd