Rauwolfia alkaloids deserpidine

The pharmacological properties of deserpidine are similar to those of reserpine, causing sedation and tranquilization. Toxic effects from high doses include drowsiness, depression, nansea, diarrhea, abdominal cramps, and hypotension. It is less toxic than reserpine. However, the poisoning effects may be greater than those of other Rauwolfia alkaloids, such as rescinnamine. An oral LD50 value in mice is 500 mg/kg. 

Members of the yohimbine alkaloid family possess a characteristic penta-cyclic indole skeleton 1. Representative compounds in this family include the Rauwolfia alkaloids, such as reserpine (2) and deserpidine (3), and the yohimbines (4-9). These compounds exhibit a wide range of medicinal properties (1,2). Reserpine, for example, has been used extensively in the treatment... 

In 1918 the traditional Indian remedy rauwolfia was reported to be useful in the treatment of hypertension. Reexamination of this material led to the isolation of reserpine (28 R1 = Me, R2 = 3,4,5-trimethoxybenzoyl) which was shown in 1952 to have hypotensive and tranquilizing effects. Other alkaloids such as deserpidine (28 R1 = H, R2 = 3,4,5-trimethoxybenzoyl) and rescinnamine (28 R1 = Me, R2 = 3,4,5-trimethoxycinnamoyl) were later isolated. They are useful when alternative, more potent drugs are not well tolerated. 

Deserpidine (Harmonyl) is an alkaloid from Rauwolfia root. 

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. 

Yohimbine alkaloids possess a characteristic pentacyclic indole skeleton. Representative members of the family include the rauwolfia (reserpine and deserpidine) and the yohimbines. A wide range of medicinal properties has been associated with these compounds and extensive studies have been carried out on the synthesis of the yohimbine alkaloids, including enantioselective syntheses [13,14]. In our approach, we view the acetylenic sulfoxide as a two-carbon synthon for the C3-C14 segment of the pentacyclic system (see 27). The chirali-... 

It is a common knowledge that plants are useful sources of many valuable medicines. Among these medicines several indole alkaloids can be found, e.g. reserpine and deserpidine from Rauwolfia serpentina ajmalicine and yohimbine from Corynanthe yohimhe vinblastine and vincristine from Catharanthus roseus just to mention a few of them. 

Reserpine is found in the roots of Rauwolfia serpentina (Apocynaceae) along with the related alkaloids resicinnamine, deserpidine and ajmaltne. The main actions are hypotensive, sedative and tran-quillising. Ajmaline is of benefit for heart arrhythmias (Samuelsson 1992). 

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