Ochrosia poweri

The alkaloids ochropamine (CCCLVII-C) and ochropine (CCCLVII-D) from Ochrosia poweri are the only representatives of the growing 2-acylindole class so far encountered in the genera under study (192d). The nature of the chromophore (A 243 and 315 m/x, e 18,900, 17,700) present in CCCLVII-C was determined both by alkaline degradation to 2-acetyl-1,3-dimethylindole and by comparison with the known 1-keto-1,2,3,4-tetrahydrocarbazole. The presence of carbomethoxyl (5.78 fi,... 

Alstonia constricta F. Muell. (36) alstonine, R. vomitoria (37) aricine, Aspidosperma marcgravianum Woodson (37) reserpiline, R. decurva Hook. (38) isoreserpiline, R. cambodiana Pierre (39), R. decurva, and Ochrosia poweri F. M. Bailey serpentinine, R. vomitoria (37) and R. javanica (34). 

Cabucala torulosa Pichon, a rare species from the Mandana Forest Reserve in Madagascar, contains (—)tetrahydroalstonine in its leaves, and (—)-aricine and (—)-cabucine (81) in its stem and root bark. " A re-examination of elliptamine, isolated some years ago from Ochrosia poweri Bail., has shown that it is in fact identical with reserpiline. 

The conversion of gardnerine (1) to ochropine (39), a 2-acyl indole alkaloid isolated from the stem bark of Ochrosia poweri 175. was also carried out to establish structure 39 for the latter alkaloid. The reaction sequence is shown in Scheme 10. The nitrile function of 43 was converted to the carbomethoxy grouping by methanolysis. C-D ring cleavage with BrCN gave an epimeric mixture of C-3 hydroxyls which was then subjected to Cornforth oxidation to furnish 46. Decyanation of 46 and... 

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