Erythrina arborescens

In the Erythrina series, the total synthesis of ( )-erysotramidine (10), an oxo-erythrinan alkaloid, isolated from Erythrina arborescens Roxb.,13 has been... 

The pod walls of Erythrina arborescens Roxb. contain a number of alkaloids of the Erythrina group, together with hypaphorine and a new base, erysodino-phorine, which has the structure (11), since it can be hydrolysed to hypaphorine and erysodine. ... 

Erysophorine (13) was isolated from the water-soluble extract of the seeds of E. arborescens Roxb. (37). The molecular formula C32H38N304.CI was established by analysis. The mass spectrum of 13 gave no molecular ion but exhibited fragments consistent with a 1,6-diene Erythrina alkaloid and a carboxylated indole-3-alkylamine. Erysophorine appeared to be a combined alkaloid, and its UV spectrum was similar to that of an equimolar mixture... 

The following species of Erythrina possess nearly identical lectins arborescens, caffra, corallodendron, cristagalli, fladelliformis, lalissima, litosperma, lysislemon, perrieri, stricta, suberra, zeyheri. 

The isolation of these new 8-oxo-alkaloids adds two further examples to a growing family of 8-oxo-erythrina alkaloids, other examples being erythrabine (Id) and erysotramidine (If) (Ito et al. 1973) isolated from E.arborescens and crystamidine (In) from E.crysta-galli (Ito et al. 1973) whilst two other oxo-alkaloids have been found in Cocculus laurifolius (Uprety and Bhakuni 1975), (Bhakuni and Jain 1980). 

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