Erythrophleum alkaloids

From the bark of Erythrophleum chlorostachya, a tall Australian tree, norery-throstachaldine and other highly cytotoxic alkaloids have been isolated (101). 

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All the erythrophleum alkaloids examined in detail so far are of the same type, viz., acyl esters of either monomethylaminoethanol, e.g., erythrophleine and coumingidine or dimethylaminoethanol, such as cassaine or cassaidine. The acyl substituents are complex, yield 1 7 8-trimethylphenanthrene on selenium dehydrogenation, and contain at least one hydroxyl group, which may be acylated by an aliphatic acid, e.g., coumingine forms three components on hydrolysis. 

The 2-methylaminoethyl esters of the Erythrophleum alkaloids readily rearrange to the amides and this has in the past caused some confusion. The conditions for the isolation of the esters from Erythrophleum chlorostachys have now been carefully defined.40 3/3-Acetoxynorerythrosuamine (39) is a new highly cytotoxic alkaloid41 from this source. 

A useful review of the diterpene alkaloids has appeared.Partition chromatography of the Erythrophleum alkaloids from the bark of Erythrophleum guineense has led to the isolation of 8-dehydrocassaic acid. This may arise by the dehydration of a 6a-hydroxy-alkaloid (6a-hydroxycassaine), since erythro-phleguine (6a-hydroxycassamine) gives 8-dehydrocassamic acid on hydrolysis. 

A review on the occurrence, chemistry, and pharmacology of Erythrophleum alkaloids has appeared. The Euphorbia alkaloids have also been reviewed. 

These Erythrophleum alkaloids, when they can be synthesized cheaply, hold much promise as digitalis substitutes in the treatment of congestive heart failure. 

Bisbenzylisoquinoline Alkaloids by Marshall Kulka The Cularine Alkaloids by R. H. F. Manske. a-Naphthaphenanthridine Alkaloids BY R. H. F. Manske The Erythrophleum Alkaloids by G. Dalma. The Aconitum and Delphinium Alkaloids by E. S. Stern... 

The Erythrophleum alkaloids represent a clearly defined class, both as regards their chemical structure and pharmacological properties. They are alkamine esters of monocarboxylic acids of the diterpene series and possess remarkable cardiac activity of the digitalis type coupled with very intense local anesthetic action. 

Erythrophleum alkaloids. Group of diterpene alkaloids occurring in Erythrophleum species (Fabaceae). They are derivatives (esters and amides) of cassaic... 

Cassane is the basic skeleton of cassaic acid, the parent diterpenoid of alkaloids from the bark of Erythrophleum guinese and other Erythrophleum species (Fa-baceae). These act as local anaesthetics, cardiotonics, antihypertonics, and also induce cardiac arrest. Erythrophleum alkaloids such as cassaidine, cassain and cassamine are 2-(iV,iV-dimethylamino)ethyl esters of cassaic acid derivatives. 

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