Synthesis of 10 stereochemically distinct bis-tetrahydrofuran intermediates for creating a library of 64 asimicin stereoisomers
摘要:
Stereoselective synthesis of 10 unique bifunctional stereoisomeric adjacent bis-THF intermediates (R = Bz), including 5.1-5.4, 5.7-5.9, 5.11, and 5.15-5.16, of 16 possible compounds, is described. The key steps used in the synthesis of these compounds included the rhenium(VII) oxide-mediated and the Co(modP)(2)-catalyzed trans oxidative cyclizations (OCs), the OsO4-catalyzed cis OC, and the Williamson's type etherification reactions. The remaining six bis-THF intermediates (R = Bn) can be prepared from 5.7-5.9, 5.11, and 5.15-5.16 (R = Bz) in two steps, including protection of the free alcohol as benzyl ether followed by the benzoate deprotection. These intermediates should provide access to all 64 asimicin stereoisomers; and their analogs. (C) 2009 Published by Elsevier Ltd.
Synthesis of 10 stereochemically distinct bis-tetrahydrofuran intermediates for creating a library of 64 asimicin stereoisomers
摘要:
Stereoselective synthesis of 10 unique bifunctional stereoisomeric adjacent bis-THF intermediates (R = Bz), including 5.1-5.4, 5.7-5.9, 5.11, and 5.15-5.16, of 16 possible compounds, is described. The key steps used in the synthesis of these compounds included the rhenium(VII) oxide-mediated and the Co(modP)(2)-catalyzed trans oxidative cyclizations (OCs), the OsO4-catalyzed cis OC, and the Williamson's type etherification reactions. The remaining six bis-THF intermediates (R = Bn) can be prepared from 5.7-5.9, 5.11, and 5.15-5.16 (R = Bz) in two steps, including protection of the free alcohol as benzyl ether followed by the benzoate deprotection. These intermediates should provide access to all 64 asimicin stereoisomers; and their analogs. (C) 2009 Published by Elsevier Ltd.
Total synthesis of 27-hydroxy-bullatacin and its C-15 epimer, and studies on their inhibitory effect on bovine heart mitochondrial complex I functions
作者:Zhiyong Chen、Subhash C. Sinha
DOI:10.1016/j.tet.2007.11.089
日期:2008.2
The total synthesis of 27-hydroxybullatacin and its C-15 epimer has been achieved using rhenium(VII) oxides-mediated and Co(modp)(2)-catalyzed oxidative cyclization (OC), diastereoselective alkynylation, Brown's enantioselective allylboration, and Grubbs' cross metathesis as the key reactions. The inhibitory effect of these compounds on the complex I function, as determined by using bovine submitochondrial particles, was in low nanomolar range. (C) 2007 Elsevier Ltd. All rights reserved.