PURPOSE: To obtain the subject derivative, represented by a specific formula, having inhibiting actions on α-glycosidases and useful as an inhibitor of the α-glycosidases, a suppressant, etc., for immunological functions in treating cancer metastasis, AIDS, etc.
CONSTITUTION: A compound of formula I [R1 and R2 are each H, formyl, carboxyl, a 1-8C alkoxycarbonyl, aminocarbonyl or a (substituted)1-8C alkyl; R3 is H, SO3H or an acyl; R4 is hydroxy, OSO3H, a 1-8C alkoxy or an acyloxy or, together with R3, may form a single bond; A is =0 or OX (X is H, SO3H or an acyl)], e.g. 1,6-anhydro-3,4-dideoxy-4-formyl-β-D-glycero-hex-3-enopyranos--2- ulose. Furthermore, the compound is preferably obtained by using, e.g. 1,6- anhydro-3,4-dideoxy-4-methyl-β-D-glycero-hex-3-enopyranos-2-ulose of formula II as a starting substance.
TSUKAMOTO MASAMITSU