Hunteria ebumea

According to a recent report on some unpublished work by Joshi and Taylor (92a), the acid hydrolysis of villalstonine affords pleiocarpamine (LXXIIa) (92b), one of the constituent bases of Pleiocarpa mutica Benth. (92c) and Hunteria ebumea Pichon (92d). 

Among the alkaloids of Hunteria ebumea Pichon (Table I) were four interrelated ones (11). Two of them, eburnamine and isoeburnamine, were diastereoisomeric pentacyclic indoles (XVII) convertible by acids into eburnamenine, an A-vinylindole (XVIII), on the one hand, and by chromic acid into eburnamonine, an V-acylindole (XIX), on the other. Reduction of eburnamonine with lithium aluminum hydride regenerated the alcohols, XVII (7,11). When eburnamonine was heated with selenium... 

Hunteracine, a remarkably stable alkaloid of Hunteria ebumea, which survives the usual methods for degrading quaternary salts and can be sublimed as its chloride or bromide salt, has the constitution (141). An indoxyl derivative obtained by... 

Hunterburnine a- and -Methochlorides. Similar to the case of bumamicine, the quaternary salts hunterburnine a- and j8-metho-chlorides were isolated from Hunteria ebumea in amounts which did not lend themselves to chemical examination and they were not volatile enough for mass spectrometric work. By physical methods they were recognized to be 5-hydroxyindoles, to contain a quaternary N-methyl and a vinyl group. Since their iodides were in a form suitable for X-ray analysis this appeared to be the method of choice for their structural elucidation which is discussed for the )3-methiodide. 

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