| abstract |
Sialic acid derivative with active ester groups expressed with the formula [I]n n Where R 1 denotes hydrogen or acetyl group, R 2 hydrogen or lower alkyl group, R 3 C 2 H 4 , C 3 H 6 or C 2 H 2 , R 4 hydroxyl group, residue left after removing hydrogen from the alcohol portion of active ester or alkyloxycarbonyloxy group, Ac acetyl group, Ph phenyl group, X oxygen or sulfur. This sialic acid derivative has high reactivity because it has active ester groups in molecules and can be used as raw material or intermediate for synthesis of various sialic acid derivatives. |