Amsonia elliptica

Among plumeran alkaloids isolated from the leaves of T. coffeoides (Hazunta modesta), two minor compounds were not previously discussed (70). One was recognized as 3-oxotabersonine (68, C21H22N203, MP 151.5-153°C, [a]D -11.4°) identical to the product isolated by Sakai from the seeds of Amsonia elliptica (198). Compound 68 was also obtained in 32% yield by KMn04 oxidation of tabersonine (67). 

The other antirhine iVb-metho salt, namely, antirhine Ab-(3-methochloride (13) has been isolated from Amsonia elliptica Roem. and Schult. (27). Demethylation... 

Tetrahydrosecamine occurs in Amsonia elliptica, and a diastereoisomer of (- )-5,6,5, 6 -tetrahydropresecamine mPandaca minutiflora. °... 

The Nb-oxide of tabersonine (78) is reported to occur in the seeds of Amsonia elliptica Roem. et Schult. (101), in which it is accompanied by 3-oxotabersonine (107). Four other sources of 3-oxotabersonine have also been recorded (15,93,103,109). The structure of this alkaloid was established (101) by hydrogenation to 3-oxovincadifformine, which was identified by comparison with a (racemic) synthetic sample (1), and by its preparation by oxidation of tabersonine by means of potassium permanganate (101). 

Epoxy -16 - hydroxy -16 - methoxycarbony 1 - 3 - oxo -1,2- didehydro-aspidospermidine (127) has been extracted from the seeds of Amsonia elliptica (101). However, this is almost certainly an artifact, derived by aerial oxidation of 3-oxotabersonine (107), which occurs in the same plant, or its epoxide. 

Monoterpenoid Alkaloids.—Corynantheine-Heteroyohimbine-Yohimbine Group, and Related Oxindoles. The first recorded extraction of the leaves and twigs of Peschiera laeta Mart, has yielded geissoschizol, a base not previously found in the Peschiera genus. Antirhine and, to a lesser extent, its quaternary Nb-metho-derivative, occur in the bark of Strychnos camptoneura Gilg. et Busse and in Amsonia elliptica, which also contains tetrahydrosecamine, pleiocarpamine,... 

Tetrahydrosecamine has been isolated from Amsonia elliptica. ( )-Di-demethoxycarbonyltetrahydropresecamine (104) and ( )-didemethoxycarbonyl-tetrahydrosecamine (105) have been synthesized the essence of the sequence is... 

Amsonia elliptica Roem. et Schult. Amsonia tabernaemontana Walt Aspidosperma album Vahl. (R. Benth. ex M. Pichon)... 

The occurrence of ajmalicine and lochnericine in the roots of Catharanthus roseus has again been noted " the same two alkaloids are biosynthesised, together with catharanthine, vindoline, and vinblastine, in the callus tissue culture of the same species. Ervine (rauniticine) occurs in the aerial parts of Vinca major,and tetrahydroalstonine in the seeds of Amsonia elliptica and in the leaves of Hunteria elliottii (Stapf.) Pichon. ... 

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