E. Schreiner, Rudolf Christian, E. Zbiral
Jan 22, 1990
Citations
0
Influential Citations
17
Citations
Journal
European Journal of Organic Chemistry
Abstract
The methyl ester of N-acetylneuraminic acid β-methyl ketoside (Neu5Ac1Me-2β-Me) (1) is used as common starting material for the synthesis of the title compounds. Combined derivatization reactions with reagents thiophosgene, p-cresol, benzoyl chloride, and acetic anhydride/pyridine lead to the thiocarbonate derivatives 2, 6–8, and 12. Further transformation with iodomethane yields the 9-iodo compounds 3, 9, and 13, which are reduced by tributyltin hydride to the deoxy derivatives 4, 10, and 14. Hydrolysis of 14, 10, and 4 affords the desired 9-deoxy, 7,9-dideoxy-, and 4,7,9-trideoxy-N-acetylneuraminic acids 15 (9-d-Neu5Ac), 11 (7,9-d2-Neu5Ac), and 5 (4,7,9-d3-Neu5Ac), respectively. — The sialic acid analogues 11 and 5 were activated by CMP-sialate synthase [E,C.2.7.7.43] to an extent of 30–40 and 50–60%, respectively, relative to N-acetylneuraminic acid.