Rauwolfia canescens

Ajmaline isolated from Rauwolfia sp. roots Rauwolfia serpentine Benth., Rauwolfia vomitoria Afr., Rauwolfia canescens L. 

Threshed roots of Rauwolfia canescens L. extracted with 5% solution of acetic acid at room temperature for 24 h. Then extract was decanted to flask. This extract was alkalified with ammonia (alkaloid salts were converted to alkaloid bases). The obtained thus method solution was extracted with chloroform 3 or more times. Then chloroform extract was chromatographed on column through Al203 sorbent. After chromatography ajmalin was obtained, which had melting point at 205°C (recyrstallization from methanol). 

Belikov A.S. Alkaloids of Rauwolfia canescens L.//Chemistry of natural compounds 1969, 3. P.64... 

An alkaloid isolated from the root of Rauwolfia canescens (Apocynaceae). 

Yohimbine is a major carboline alkaloid in the bark of Pausinystalia species, such as Pausinystalia yohimbe (Corynanthe yohimbe), Pausinystalia macrocerus, Pausinystalia paniculata, and Pausinystalia trillesi. It is also found in Pseudocinchona africana and Rauwolfia canescens. 

Deserpidine is found and extracted from the roots of Rauwolfia canescens L., and Apocyanaceae. Therapeutically, it is used as an antihypertensive agent. 

Rauwolfia is the dried rhizome and roots of Rauwolfia (sometimes Rauvolfia) serpentina (Apocynaceae) or snakeroot, a small shrub from India, Pakistan, Burma, and Thailand. Other species used in commerce include R. vomitoria from tropical Africa, a small tree whose leaves after ingestion cause violent vomiting, and R. canescens = R. tetraphylla) from India and the... 

Rauwolfia serpentina Benth, which derives its name from Leonhart Rauwolf, a 16th century botanist, and its serpentine root (Figure 56.1), has long been used in India for a variety of ailments. The discovery of its tranquilizing action, particularly in lowering the blood pressure, led to its introduction into Western medicine. The Rauwolfia alkaloids are derived from a family of tropical and semitropical plants related to oleander and periwinkle. They vary from small shrubs to tall trees. The important species from which the alkaloids are derived include Rauwolfia serpentina (Ophioxylon serpentinum or Indian snakeroot), R. micrantha, R. vomitoria, and R. hirsuta (Canescens heterophylla). 

The occurrence of reserpine has been reported from all Rauwolfia species, with the exception of about half a dozen in which it is probably present in minute amounts. Renoxidine, the A-oxide of reserpine, has been isolated from R. vomitoria, R. serpentina, and R. canescens, and it may not be a natural product, since it could have been derived by autoxi-dation of the tertiary base which is abundant in these plants. If it was an artifact, the occurrence of other analogous A-oxides should have been noted, but so far the only other recognized case is raujemidine A-oxide, which is found along with the parent alkaloid, raujemidine (a minor base of R. canescens). In contrast to reserpine, deserpidine and rescinnamine are of restricted distribution, each being recognized so far in about ten species only. 

Reserpine occurs in the roots of Rauwolfia serpentina and other Rauwolfia species, such as R. micrantha, R. canescens, and R. vom-itoria Hook. It is used therapeutically as an antihypertensive agent and a tranquilizer. Its use has been reduced significantly because of toxic side effects. 

Reserpine, which is an important antihypertensive medicine, has also been obtained from other Rauwolfia species such as R. heterophylla, R, canescens, R. Mr-suta, R, vomitoria, R, tetraphylla, and R. verticillata. 

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