Formal Synthesis of (−)-Neopeltolide Featuring a Highly Stereoselective Oxocarbenium Formation/Reduction Sequence
作者:Dionicio Martinez-Solorio、Michael P. Jennings
DOI:10.1021/jo100443h
日期:2010.6.18
The formal synthesis of the unnatural (−)-neopeltolide core is discussed in detail. Efficient application of the Evans’ protocol for the synthesis of 1,3-syn-diols via an intramolecular hetero-Michael addition followed by reductive deprotection of the resulting benzylidene acetal allowed for swift access to the δ-lactone. Central to the synthetic approach is a tandem nucleophilic addition−diastereoselective
An antimalarial lipopeptide, ikoamide, was isolated from an Okeania sp. marine cyanobacterium. Its gross structure was established by spectroscopic analyses, and the absolute configuration was clarified based on a combination of chiral phase HPLC analyses, spectroscopic analyses, and derivatization reactions. Ikoamide showed strong antimalarial activity with an IC50 value of 0.14 mu M without cytotoxicity against human cancer cell lines at 10 mu M.