Tabernaemontana glandulosa

The stems and leaves of Ghanaian Tabernaemontana glandulosa Stapf. contain73" tabernulosine (101), a new base of the picrinine type, which exhibits unusual substitution in the aromatic ring however, details of its structure elucidation are not yet available. 

A new alkaloid, 3-hydroxycoronaridine, has been found in Tabernaemontana glandulosa Stapf 115 its structure was deduced from its spectra, particularly its mass spectrum, and confirmed by reduction with sodium borohydride, which gave coronaridine (240). The stems of a related species, T. flavicans, collected in Peru, contain ibophyllidine and ibophyllidine N-oxide.116... 

The second dimeric alkaloid conophyllidine (304) is identical in all respects with conophylline except for replacement of the epoxide function at positions 14 and IS of the tabersonine epoxide unit by a double bond. Conophylline has also been subsequently isolated from the South American species, Tabernaemontana glandulosa [182], and from the Thai species, Ervatamia microphylla [183]. It has also been reported from another Malaysian species, Ervatamia polyneura, under the name polyetvine [184]. The leaf extract of Ervatamia polyneura also yielded the related dimer, polyervininc (306), which is similar to conophylline except for the aromatic portion of the vincadifformine unit which now possesses an indoline dione chromophore, existing predominantly in its zwitterionic quinoniminium form. 

Tabernulosine and 12-demethoxytabernulosine, two new alkaloids which occur with vincadiffine in the leaves and stems of W. African Tabernaemontana glandulosa Stapf, prove to be 10,12-dimethoxy-... 

Alkaloid from twigs and leaves of Tabernaemontana glandulosa (Apocynaceae). Cryst. (Me2CO). Mp 126-131°. Md +0.2 (c, 0.42 in CHCI3). 

Achenbach H, Raffelsberger B 1980c Constituents of west African medicinal plants. Part 3. 19-ethoxycoronaridine, a novel alkaloid from Tabernaemontana glandulosa. Phytochemistry 19 716-717... 

Achenbach H, Raffelsberger B, Addae-Mensah I 1982 Alkaloids in Tabernaemontana species, 8. Tabernulosine and 12-demethoxy-tabernulosine, two new alkaloids of the picrinine-type from Tabernaemontana glandulosa. Justus Liebigs Ann Chem 1982 830-844... 

In the course of chemical investigation on Tabernaemontana, Achenbach et al. (116) isolated from T. glandulosa, from Sierra Leone and Nigeria, two new alkaloids, tabemulosine (42) and 12-demethoxytabemulosine (43). 

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