Synthesis and Absolute Configuration of Zonarol. A Fungitoxic Hydroquinone from the Brown Seaweed Dictyoptfris Zonarioides(1)
摘要:
AbstractA total synthesis of both the enantiomers of zonarol 1 was accomplished. Measurements of the ORD‐CD spectra of two bicyclic intermediates coupled with direct comparison of the natural and synthetic zonarol 1 established the absolute configuration of the naturally occurring (+)‐zonarol 1 as 1R, 4aR, 8aR.
An efficient approach to chiral nonracemic trans- and cis-decalin scaffolds for drimane and labdane synthesis
作者:Gian Piero Pollini、Anna Bianchi、Alberto Casolari、Carmela De Risi、Vinicio Zanirato、Valerio Bertolasi
DOI:10.1016/j.tetasy.2004.07.064
日期:2004.10
Optically active trans- and cis-ring junction decalinic intermediates, which represent useful precursors for the synthesis of more complex natural targets, have been conveniently prepared starting from the β-ketoester 2 obtained by standard chemistry from β-ionone and dimethyl carbonate. The chiral auxiliary (−)-menthol, easily attached to 2 through DMAP-catalyzed transesterification, allowed a clean separation