Syntheses in enantiopure form of four diastereoisomeric naphthopyranquinones derived from aphid insect pigments
作者:Rachna Aggarwal、Robin G. F. Giles、Ivan R. Green、Francois J. Oosthuizen、C. Peter Taylor
DOI:10.1039/b414213f
日期:——
The first syntheses are described of the four enantiopure naphthopyranquinones (1R,3R,4S)- and (1R,3R,4R)-3,4-dihydro-4,7,9-trihydroxy-1,3-dimethylnaphtho[2,3-c]pyranquinone (quinone A 1 and quinone A' 2) and their two C-3 epimers, the (1R,3S,4S)- and (1R,3S,4R)-diastereoisomers 5 and 6, using enantiopure lactate as the source of asymmetry. Key factors in these syntheses are the maintenance of stereochemical
第一次合成描述了四个对映体纯的萘并吡喃醌(1R,3R,4S)-和(1R,3R,4R)-3,4-二氢-4,7,9-三羟基-1,3-二甲基萘[2,3 -c]吡喃醌(醌A 1和醌A'2)及其两个C-3差向异构体,(1R,3S,4S)-和(1R,3S,4R)-非对映异构体5和6,使用对映体纯乳酸作为不对称的来源。这些合成中的关键因素是整个序列中立体化学完整性的维持以及酚醛醛钛酸酚盐的分子内非对映选择性环化。对于这些环化,解释了不同程度的非对映选择性,以及产物2-苯并吡喃-4,5-二醇的立体化学。