Study of Uridine 5′-Diphosphate (UDP)-Galactopyranose Mutase Using UDP-5-Fluorogalactopyranose as a Probe: Incubation Results and Mechanistic Implications

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• 作者：Geng-Min Lin ; He G. Sun ; Hung-wen Liu
• 刊名：Organic Letters
• 出版年：2016
• 出版时间：July 15, 2016
• 年：2016
• 卷：18
• 期：14
• 页码：3438-3441
• 全文大小：374K
• 年卷期：0
• ISSN：1523-7052

文摘

Uridine 5′-diphosphate-5-fluorogalactopyranose (UDP-5F-Galp, 7) was synthesized, and its effect on UDP-Galp mutase (UGM) was investigated. UGM facilitated the hydrolysis of 7 to yield UDP and 5-oxogalactose (24), but no 11 was detected. ¹⁹F NMR and trapping experiments demonstrated that the reaction involves the initial formation of a substrate–cofactor adduct followed by decomposition of the resulting C5 gem-fluorohydrin to generate a 5-oxo intermediate (10). The results support the current mechanistic proposal for UGM and suggest new directions for designing mechanism-based inhibitors.