著者
磯部 稔 Uyakul D. 高橋 宏幸 後藤 俊夫
出版者
天然有機化合物討論会
雑誌
天然有機化合物討論会講演要旨集
巻号頁・発行日
no.31, pp.396-403, 1989-09-17

Lampteroflavin (1), a riboflavin α-D-riboside was isolated in extraordinary small amount from the luminous mushroom, Lampteromyces japonicus (Fig 1), which was available only two weeks in a year. Extraction method was improved to utilize only alive gills under aeration instead of using the whole body (Fig 3), and the method was established as Scheme 1. It's structure has been elucidated by chromatographic and spectroscopic analyses(1). It's fluorescence spectrum was identical to the bioluminescence spectrum of the mushroom, having maximum at 524nm (Fig 2). We concluded that 1 was responsible to the bioluminescence mechanism as the light emitter, since 1 was only the fluorescent constituent in fresh gills. Previous report that illudin S (lampterol) or ergosta-4,6,8(14),22-tetraen-3-one(2) could be the emitter is thus unlikely judging from the weak fluorescent intensity and the different maximum wavelength from that of mush-room bioluminescence. Lampteroflavin (Table 1) was hydrolyzed with dil. mineral acid to give riboflavin and D-ribose. Riboflavin was identified by HPLC, ^1H NMR, UV, Fluorescence and FAB mass spectrometry. D-ribose was acetylated and then confirmed by ^1H NMR, CD and tandem mass spectrometry. Riboflavin and D-ribose was connected together with α-glycosidic linkage which was determined by ^<13>C NMR of the anomeric carbon (δ=103.2ppm)(3), NOSEY spectrum (H-1" being close to H-3" and H-5') and ^1H NMR pattern of anomeric proton. The total structure of lampteroflavin was confirmed through its chemical synthesis.
著者
磯部 稔
出版者
The Society of Synthetic Organic Chemistry, Japan
雑誌
有機合成化学協会誌 (ISSN:00379980)
巻号頁・発行日
vol.41, no.1, pp.51-61, 1983-01-01 (Released:2010-01-22)
参考文献数
25
被引用文献数
2 5

A general synthetic strategy to ansa-macrocyclic lactam, maytansinoid, is described via a common intermediate for maytansine, maytansinol, maysine and N-methylmaysenine. The key reactions are focused on the successful stereochemical control by diastereoselective asymmetric induction involving heteroconjugate addition, epoxidation, aldol reaction etc. The principle was mainly based on chelational and conformational control in acyclic system, and all of the seven asymmetric centers of maytansinol has been introduced before closing 19-membered lactam ring.