Degradative studies of the anticancer macrolide palmerolide A have resulted in re-assignment of the C-7,C-10, and C-11 stereocenters. (c) 2007 Elsevier Ltd. All rights reserved.
Trimethylsilyl Trifluoromethanesulfonate (TMSOTf) Assisted Facile Deprotection of <i>N</i>,<i>O</i>-Acetonides
作者:Kevin W. C. Poon、Kimberly M. Lovell、Kendra N. Dresner、Apurba Datta
DOI:10.1021/jo7021923
日期:2008.1.1
[GRAPHICS]Employing TMSOTf as an easily available reagent, we have developed a mild and efficient method for the deprotection of both terminal and internal NO-acetonide functionalities. Various regularly used protecting groups and common organic functional moieties were found to be unaffected by the described reaction conditions. In a few representative examples, the present method was also extended to deprotect acetonides obtained from 1,2-, and 1,3-terminal diols. The acetonide deprotection protocol described herein is expected to be a useful addition to the presently available methods for performing the above transformation.
Total Synthesis of the Potent Antitumor Polyketide (−)-Callystatin A
作者:Luiz C. Dias、Paulo R. R. Meira
DOI:10.1021/jo050352u
日期:2005.6.1
A highly convergent and efficient totalsynthesis of the potentantitumor polyketide (−)-callystatin A is described. The synthesis required 19 steps from N-propionyl oxazolidinone 23 and produced the desired product in 3.5% overall yield.
Degradative studies of the anticancer macrolide palmerolide A have resulted in re-assignment of the C-7,C-10, and C-11 stereocenters. (c) 2007 Elsevier Ltd. All rights reserved.