Cycloeucalenol structure

Rahier, A., Taton, M. and Benveniste, P. (1989) Cycloeucalenol-obtusifoliol isomerase. Structural requirements for transformation or binding of substrates and inhibitors. Eur. J. Biochem., 181,615-26. 

The confirmation of this structure and proof of the stereochemistry of the skeleton was provided by the following correlation of dihydrocyclo-buxine-D with cycloeucalenol (183, 191). 

Further new natural products are (38) from the toxic micro-organism Fusarium sporotrichioides 921,30 (39) and (40) from olive oil,31 triphyllol (41) from Adeno-phora triphylla (Campanulaceae),32 and cyclonervilol (42) and cyclohomonervilol (43) from Nervilia purpurea (Orchidaceae). The structure of (43) was supported by its conversion into cycloeucalenol.33 Two new xylosides from Cimicifuga japonica (Ranunculaceae) are based on the genuine sapogenins (44) and (45). Treatment of... 

FIGURE 1. Proposed reaction pathway for A -sterol-A -reductase. Structural and chai ge analogies between the cationic high energy intennediates involved in A 7-sterol A7-reductase (a7-SR), cycloeucalenol isomerase (COI), A8ri4 sterol Al4-reductase (A14-SR), and A -A 7-sterol isomerase (A -A 7-SI) and the protonated forms of tridemorph 1, 6,7-diazacholest-8(14)-en-3(3-ol 2 and 6-aza-B-homocholest-7-en-3p-ol 3. 

---