Colubrinol

Colubnnol and colubrinol acetate arc isolated from Colubrina texensis Gray (Rhamnaceae) along with maytanbutine. Colubrinol is also isolated from Trewia nudiflora (Euphorbiaceae). The structures for colubrinol and colubrinol acetate were established by high resolution ms and the comparison of tlieir nmr spectra with that of the known maytanbutine. 

Wani, M.C., Taylor, H.L., Wall, M.E. Plant Antitumor agents colubrinol acetate and colubrinol, antileukaemic ansa macrolides from Colubrina texensis. J. Chem. Soc. Chem. Comm. 1973, 390... 

The crystal and molecular structure and the absolute configuration of maytansine (73) were studied using its 3-bromopropyl ether [121] and the cytotoxicity of 73 [122] was reported. Several other maytansinoids, such as colubrinol (74), normaytancyprine (75) [123], 10-epitrewiasine (76), trewiasine (77) and nortrewiasine (78) [124], were isolated from Putterlickia verrucosa and Trewia nudiflora, respectively, and the structure elucidation, and the structural requirements for antileukemic activity of natural and semisynthetic maytansinoids were reported [120, 125]. As described above, maytansine (73) was isolated initially from a higher plant, although it was evident that the content of this compound was extremely low. 

Colubrinol acetate Colubrina texensis Gray (Rhamnaceae)... 

Wani, M. C., H. L. Taylor, and M. E. Wall Plant Antitumour Agents Colubrinol Acetate and Colubrinol, Antileukaemic Ansa Macrolides from Colubrina texensis. Chem. Commun. 390 (1973). 

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