A fine addition! A highlyenantioselective and efficient procedure for the amino‐alcohol–zinc‐catalyzedaddition of trimethylsilylacetylene to aromatic, α,β‐unsaturated, and aliphatic aldehydes has been developed (see scheme; R=aryl, alkynyl, or alkyl; TMS=trimethylsilyl; TBDMS=tert‐butyldimethylsilyl). The present protocol was successfully applied in the concise synthesis of the natural products marine
很好的补充!已开发出一种高度对映选择性和高效的程序,用于氨基醇锌催化的三甲基甲硅烷基乙炔加成到芳族,α,β-不饱和和脂肪族醛中(见方案; R =芳基,炔基或烷基; TMS =三甲基甲硅烷基; TBDMS =叔丁基二甲基甲硅烷基)。本协议已成功地应用于天然产物海洋炔醇和法卡林二醇的简明合成中。
Stereoselective Approaches for the Total Synthesis of Polyacetylenic (3<i>R</i>,8<i>S</i>)-Falcarindiol
Falcarindiol (1) was isolated as an algicidal principle against the harmful red tide dinoflagellate, Heterocapsa circularisquama, from Notopterygii Rhizoma through bioassay-guided separation. In order to determine the ambiguous absolute structure of this active principle, all three stereoisomers as well as falcarindiol (1) were synthesized. As a result of intensive analysis of their physicochemical properties, the configuration of I was revealed to be 3R,8S. On the other hand, (3S,8S)- and (3S,8R)-isomers were found to exhibit more potent algicidal activity than (3R,8S)-falcarindiol (1) isolated from Notopterygii Rhizoma. In addition, the diyne moiety of 1 was established as the crucial structural requirement for algicidal potency. (C) 2010 Elsevier Ltd. All rights reserved.