An intramolecular Pauson-Khand reaction has been used in the construction of the tricyclic core common to the hamigeran terpenes. For effective cyclization, it was necessary to tether the olefin-containing moiety to the aromatic framework to reduce its conformation mobility; this was accomplished using a silylene protecting group. Efficient construction of the aryl enyne from a salicylic acid derivative was accomplished via ortho lithiation and Sonogashira cross-coupling chemistry.
Stereo- and Regioselective Glycosylations to the Bis-<i>C</i>-arylglycoside of Kidamycin
作者:ZhongBo Fei、Frank E. McDonald
DOI:10.1021/ol7014219
日期:2007.8.1
explorations toward the total synthesis of the antitumor anthrapyran natural product kidamycin, the regioselective introduction of aminosugars angolosamine and vancosamine as C-arylglycosides has been accomplished onto hydroxylated anthrapyran aglycones. Specifically, the 9,11-dihydroxylated anthrapyran A undergoes sequential glycosylations with angolosamine synthon B and vancosamine synthon C to regio-
在抗肿瘤蒽吡喃天然产物卡达霉素的全合成探索中,区域选择性地将氨基糖安戈洛胺和万古胺作为C-芳基糖苷引入羟基化蒽吡喃苷元上。具体而言,9,11-二羟基化蒽吡喃 A 与安戈洛胺合成子 B 和万古胺合成子 C 进行连续糖基化,以区域选择性和立体选择性地提供与卡达霉素 C-糖苷模式相对应的双-C-糖苷 D。
A Pauson−Khand Approach to the Hamigerans
作者:Christian E. Madu、Carl J. Lovely
DOI:10.1021/ol7018604
日期:2007.11.1
An intramolecular Pauson-Khand reaction has been used in the construction of the tricyclic core common to the hamigeran terpenes. For effective cyclization, it was necessary to tether the olefin-containing moiety to the aromatic framework to reduce its conformation mobility; this was accomplished using a silylene protecting group. Efficient construction of the aryl enyne from a salicylic acid derivative was accomplished via ortho lithiation and Sonogashira cross-coupling chemistry.