65 新規ポリケタイド骨格を持つ(+)-ハレナキノールおよび(+)-ハレナキノンの全合成.理論計算によって決定した絶対構造の実験的証明(口頭発表の部)

概要

論文の詳細を見る
Theory and theoretically obtained results themselves naturally want to be proved in an experimental way. Recently Kitagawa and we have theoretically determined the absolute configuration of a series of novel pentacyclic polyketides, halenaquinol (1) and halenaquinone (2), isolated from tropical marine sponges, to be 12bS by the application of the x-electron SCE-CI-dipole velocity MO method to the calculation of CD spectra. Here we report the experimental proof of their absolute stereostructures theoretically determined, by describing the first total synthesis of (+)-halenaquinol 1 and (+)-halenaquinone 2. Optically pure (8aR)-(-)-Wieland-Miescher ketone (4) was converted to enone (+)-(12). The Diels-Alder reaction of 3,6-dimethoxybenzocyclobutene (18) and (+)-12 gave compound (+)-(19) of a tetracyclic skeleton, which was converted to halenaquinol dimethyl ether (12bS)-(+)-(3). All of the spectroscopic data of the synthetic sample of 3, including the chiroptical data of [α]_D and CD spectra, were completely identical with those of the authentic sample derived from natural halenaquinol. Dimethyl ether (12bS)-(+)-3 was converted to halenaquinone (12bS)-2 and finally to halenaquinol (12bS)-1. We have thus succeeded in the experimental verification of their absolute configurations theoretically determined. The present results have established the reliability of the x-electron SCF-CI-DV MO method which is useful for the theoretical determination of the absolute stereochemistry of twisted x-electron systems.
天然有機化合物討論会の論文
1988-09-26

65 新規ポリケタイド骨格を持つ(+)-ハレナキノールおよび(+)-ハレナキノンの全合成.理論計算によって決定した絶対構造の実験的証明(口頭発表の部)

スポンサーリンク

概要

著者

関連論文

スポンサーリンク