Strict stereocontrol by 2,4-O-di-tert-butylsilylene group on β-glucuronylations
Takayuki Furukawa1, Hiroshi Hinou, Shin-Ichiro Nishimura
1Graduate School of Life Science and Frontier Research Center for Post-Genome Science and Technology, Hokkaido University, N21, W11, Sapporo 001-0021, Japan.
Abstract:
Strict β-controlled glucuronylations without classical neighboring-group participation were achieved by the assistance of a 2,4-O-di-tert-butylsilylene group. Comparison of activation conditions and conformational analysis indicated that the strict β-selectivity was achieved by steric hindrance of the 2,4-O-di-tert-butylsilylene group and not by complex glycosyl intermediates.
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