“Cassette” In Situ Enzymatic Screening Identifies Complementary Chiral Scaffolds for Hydrolytic Kinetic Resolution Across a Range of Epoxides
作者:Sangeeta Dey、Douglas R. Powell、Chunhua Hu、David B. Berkowitz
DOI:10.1002/anie.200701280
日期:2007.9.17
‘Cassette’-ISES (In Situ Enzymatic Screening) Identifies Complementary Chiral Scaffolds for Hydrolytic Kinetic Resolution Across a Range of Epoxides A new ‘Cassette’-In Situ Enzymatic Screen (ISES) for combinatorial catalysis is introduced. This allows the experimentalist to obtain an information-rich readout, in real time, providing an estimate of the sense and magnitude of enantioselectivity across more than one substrate. In its first iteration, the screen identified CoIII-salen catalysts with β-pinene- and α-naphthylalanine-derived chiral scaffolds with broad, yet complementary, substrate specificities.
Total synthesis and revision of the absolute configuration of seimatopolide B
steps involved are Jacobson hydrolytic kinetic resolution, proline-catalyzed α-hydroxylation, Yamaguchi esterification and ring-closing metathesis. This asymmetric total synthesis necessitates the revision of the originally assigned (3R, 6S, 9S)-configuration to (3S, 6R, 9R).