Total synthesis and confirmation of the absolute stereochemistry of semiviriditoxin, a naphthopyranone metabolite from the fungus Paecilomyces variotii
作者:Nichole P.H. Tan、Christopher D. Donner
DOI:10.1016/j.tet.2009.03.016
日期:2009.5
The first total synthesis of (S)-semiviriditoxin 2 is described. The approach utilizes a tandem Michael–Dieckmann reaction between ortho-toluate 5 and dihydropyran-2-one 6 to construct the naphthopyranone core, the dihydropyran-2-one 6 being prepared from (R)-1,2-epoxy-4-butanol. Spectroscopic comparison of synthetic (S)-semiviriditoxin 2 with (R)-semivioxanthin 3, prepared in four steps from (R)-propylene
描述了(S)-半viriditoxin 2的第一个全合成。该方法利用邻甲苯甲酸酯5和二氢吡喃-2-酮6之间的串联Michael-Dieckmann反应来构建萘吡喃酮核,二氢吡喃-2-酮6由(R)-1,2-环氧-4-丁醇制备。由(R)-环氧丙烷分四个步骤制得的合成(S)-半viriditoxin 2与(R)-semivioxanthin 3的光谱比较证实了天然半viriditoxin的(S)-立体化学拟青霉。