Synthesis and determination of absolute configuration of tetracetate 4a-carba-d-xylofuranoside

The synthesis of carbasugar analogue tetracetate 4a-carba-d-xylofuranoside (1) was reported. The new route involved the conversion of d-(−)-tartatic acid into an enyne compound, which was then cyclized via a key ring-closing enyne metathesis to form the key intermediate 1-vinyl cyclopentene 9, which was then stereoselectively converted to our target. The absolute configuration of the enyne was determined by modified Mosher's method, while that of tetracetate 4a-carba-d-xylofuranoside by ROSEY spectroscopy and γ-gauche effect.