Asymmetric Synthesis of Anthracyclinones: Synthesis of a New Chiral AB-Synthon, (5R,6R)-6-Ethyl-5,6-dihydroxy-5,6,7,8-tetrahydro-1,4-naphthoquinone, and Its Application for a Novel Regioselective Synthesis of (-)-.GAMMA.-Rhodomycinone.
作者:Hiromichi FUJIOKA、Hirofumi YAMAMOTO、Hirokazu ANNOURA、Hiroshi MAEDA、Yasuyuki KITA
DOI:10.1248/cpb.40.32
日期:——
A new chiral AB-synthon, (5R, 6R)-6-ethyl-5, 6-dihydroxy-5, 6, 7, 8-tetrahydro-1, 4-naphthoquinone (4), for the synthesis of optically active rhodomycinones was prepared stereoselectively from a (-)-α-hydroxy ketone (6). The coupling reactions of 4 with homophthalic anhydride derivatives (9, 12) proceeded in a regioselective manner to give the tetracyclic compounds 10 and 13, respectively. Compound 10 was converted to (-)-γ-rhodomycinone (3) in a two-step sequence. The optical purity (100% ee) of 3 was unambiguously determined by high performance liquid chromatography analysis using a chiral column.
Regio- and stereo-selective construction of anthracyclinones: total synthesis of (–)-γ-rhodomycinone
作者:Hiromichi Fujioka、Hirofumi Yamamoto、Hiroshi Kondo、Hirokazu Annoura、Yasuyuki Kita
DOI:10.1039/c39890001509
日期:——
The first asymmetric synthesis of (–)-γ-rhodomycinone (1a) was achieved through a novel regioselective coupling reaction of the chiral AB-(2) and CD-building blocks (3).