Fluorous Mixture Synthesis of Four Stereoisomers of the C21-C40 Fragment of Tetrafibricin
作者:Dennis Curran、Kai Zhang
DOI:10.1055/s-0029-1219376
日期:2010.3
Fourstereoisomers of the C21-C40 fragment are synthesized in a single exercise with the aid of fluorous tagging to encode configurations at C37 and C33. After demixing and detagging, the isomers were found to have substantially identical (1)H NMR spectra. However, there were some small but reliable differences in their (13)C NMR spectra.
Synthesis of C1–C20 and C21–C40 fragments of tetrafibricin
作者:Venugopal Gudipati、Dennis P. Curran
DOI:10.1016/j.tetlet.2011.01.086
日期:2011.4
Efficient syntheses of suitably functionalized top and bottom fragments of tetrafibricin are described. The bottom fragment is prepared by two consecutive Kocienski-Julia couplings, while the top fragment synthesis features a dithiane alkylation and a Horner-Wadsworth-Emmons reaction. (C) 2011 Elsevier Ltd. All rights reserved.
Total Syntheses of the Proposed Structure of Iriomoteolide-1a, -1b and Synthesis of Three Derivatives for Structural Studies
作者:Arun K. Ghosh、Hao Yuan
DOI:10.3390/md20100587
日期:——
Iriomoteolide-1a and iriomoteolide-1b are very potent cytotoxic agents, isolated from marine dinoflagellates. We carried out the enantioselective syntheses of the proposed structures of these natural products. However, our analysis of the NMR spectra of the synthetic iriomoteolide-1a and the natural products revealed that the structures of iriomoteolide-1a and iriomoteolide-1b were assigned incorrectly. Based