Synthesis, intramolecular migrations and enzymic hydrolysis of partially pivaloylated methyl α-d-mannopyranosides
作者:Srđanka Tomić、Vesna Petrović、Maja Matanović
DOI:10.1016/s0008-6215(02)00501-3
日期:2003.3
A series of methyl O-pivaloyl-alpha-D-mannopyranosides was synthesized using pivaloyl chloride in pyridine. The 3,6-di-O-pivaloyl derivative 6 undergoes intramolecular transesterification in neutral conditions (buffer, pH 7.2) to give its 2,6-di-O-pivaloyl analogue 5. The course of this migration was followed using C-14-labelled 6. As opposed to 6 compound 5 was shown to be a good substrate for esterases present in rabbit serum. Thus, regioselective enzymic hydrolysis led to the preferential cleavage of the 2-OPiv group to yield a mixture of 2- and 6-O-monopivalates in a ratio of 1:2.6. (C) 2003 Elsevier Science Ltd. All rights reserved.
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