Lehmann J, Rob B. Enzymic glycosylation of (+/-)-(3,5/4,6)-3,6-diazido-4,5- dihydroxycyclohexene. A way to prepare stereochemically pure and enzyme resistant, basic pseudo-disaccharides as competitive enzyme inhibitors.
Carbohydr Res 1995;
276:199-208. [PMID:
8536255 DOI:
10.1016/0008-6215(95)00132-d]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
By beta-D-galactosylation of (+/-)-(3,5/4,6)-3,6-diazido-4,5-dihydroxycyclohexene, pure (+)-3,5/4,6)-3,6-diazido-4-O-(beta-D-galactopyranosyl)-5-hydrox ycyclohexene (3) was obtained. The diamine (+)-(1,3/2,6)-3,6-diamino-1-O-(beta-D-galactopyranosyl)-2-hydroxycycl ohexane, derived from compound 3 by catalytic hydrogenation, is stable against enzymic cleavage and competitively inhibits beta-D-galactosidase from Escherichia coli with a Ki-value of 5.5 mM. Sigmatropic rearrangement of 3 in methanolic solution partially led to an unseparable mixture of the regioisomers (3,5/4,6)-3,4-diazido-5-O-(beta-D-galactopyranosyl)-6-hydroxycy clohexene and (3,5/4,6)-3,4-diazido-6-O-(beta-D-galactopyranosyl)-5-hydroxycy clohexene. Catalytic hydrogenation thereof yielded an equally unseparable mixture of the diamines (1,3/2,4)-1,2-diamino-4-O-(beta-D-galactopyranosyl)-4-hydroxycyclohex ane and (1,3/2,4)-1,2-diamino-4-O-(beta-D-galactopyranosyl)-3-hydroxycyclohex ane, inhibiting beta-D-galactosidase competitively with K(i) 0.9 mM.
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