Trewia

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. 

Kang, Q.J., Zhao, P.J., He, H.P. and Shen, Y.M. (2005) Cardenolides and cardiac agly-cone from the stem bark of Trewia nudiflora. Helv. Chim. Acta, 88, 2781-7. 

Colubrina texensis Graj (Rhamnaceae) Trewia nudiflora L (Euphorbiaceae)... 

Leaves of Trewia mtdiflora L., a member of the Euphorbiaceae, were found t<5 contain a cyanopyridone alkaloid nudiflorine (CXXIX), C7H6N2O (mp 161°), reminiscent of the pyridone alkaloid ricinine (XCV) (187, 188). Hydrolysis of nudiflorine gives nudifloric acid (CXXX). Treatment of coumalic acid methyl ester (CXXXI) with ammonia... 

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. 

Four maytansinoids, trewiasine (158), treflorine, trenudine, and trenudine diacetate, have been isolated from the seeds of Trewia nudiflora and showed... 

MaytansinoMs (maitansinoids). A group of macrolide antibiotics with antileukemic, antimitotic, and cytotoxic properties from the Ethiopian shrub Maytenus ovatus, other Celastraceae, and Trewia nudiflora (Eu-phorbiaceae) as well as the Japanese mosses Isothe-cium subdiversiforme and Thamnobryum sandei (Neckeraceae). 

A number of related alkaloids, such as nudiflorine (50), are found in related plants such as those of the genus Trewia. Introduction of labeled nicotinic acid resulted in the introduction of label into several of these (Stranz and Findlay, 1985). 

Trewia nudiflora (Powell et al, 1981,1983). Several include an ususual second macrocyclic ring attached to the macrocy-clic ring found in most maytansinoids (Powell et al., 1981, 1982). 

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