Synthetic Studies on a Cyclic Hexadepsipeptide GE3: Stereoselective Construction of the Acyl Side Chain Segment
作者:Kazuishi Makino、Yoshiaki Henmi、Yasumasa Hamada
DOI:10.1055/s-2002-22724
日期:——
Stereoselective synthesis of the acyl sidechain segment 2 of GE3 (1), a potent inhibitor of cell progression of the cell cycle from the Gl to S phase, has been achieved by using Sharpless' asymmetric dihydroxylation and Evans' and Paterson's stereoselective aldol methodologies.
Total Syntheses of the Dihydrofuranonecarboxylate Natural Products Gregatin B and E: Gram-Scale Synthesis of (+)-Gregatin B and Unambiguous Assignment of the Stereostructure of (+)-Gregatin E
作者:Fabian Weber、Reinhard Brückner
DOI:10.1021/ol5032602
日期:2014.12.19
We synthesized the dextrorotatory enantiomers of gregatin B (1.3 g scale) and E, establishing their diene side chains in the last step by Heck coupling with variable iodoolefins. Their counterpart was synthesized in 30% overall yield and with high enantiopurity (97% ee) from benzyl tiglate, beginning with an asymmetric dihydroxylation. The stereostructure of gregatin E followed from HPLC comparisons between the four synthetic stereoisomers of this compound and natural gregatin E, which we isolated from Cadophora gregata.
Novel Enantioselective Synthesis of α-Methylthreonines and α,β-Dimethylcysteines