β-Benzyl 2:3-anhydro-4:6-benzylidene-D-a,lloside(Ⅳ) has been prepared from β-benzyl D-glucoside.Its behaviour towards,sodium benzylate has been obserzred to follow the same course as the corresponding a-methyl analogue,for the expected product,β-benzyl 2-benzyl-4:6-benzylidene-D-altroside(Ⅴ),is isolated.These observations demonstrate that the alteration of the glycosidic group as well as its configuration does not,at least in the case of the above compound studied,interfer with the course of formation of the ethylene oxidertng.