title: 3,4-O-Isopropyl-idene-2-C-methyl-d-galactonolactone.
abstract: X-ray crystallography unequivocally confirmed the stereochemistry of the 2-C-methyl group in the title mol-ecule, C(10)H(16)O(6), in which the 1,5-lactone ring exists in a boat conformation. The use of d-galactose in the synthesis determined the absolute stereochemistry. The crystal exists as O-H⋯O hydrogen-bonded layers in the ab plane, with each mol-ecule acting as a donor and acceptor for two hydrogen bonds.
authors.forename: N
authors.initials: N
authors.lastname: Dai
authors.forename: S F
authors.initials: SF
authors.lastname: Jenkinson
authors.forename: G W J
authors.initials: GW
authors.lastname: Fleet
authors.forename: D J
authors.initials: DJ
authors.lastname: Watkin