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Three new glycodienoid alkaloids, (+)-11 ß-methoxyglucoerysodine [3], (+)-11 ß-methoxyglucoerysovíne [4], and (+)-rhamnoerysodine [5], have been isolated from Egyptian-grown Erythrina lysistemon. The known (+ )-glucoerysodine [2} was also obtained, and lHand 13C-nmr values are presented for the dienoid and glycoside portions. A reversal of proton assignments for H-l and H-2 in all previously described dienoids is noted.Since the original identification of Erythrina alkaloids by Folkers and Major (1) in 1937, this family of compounds has grown to include some 95 members, many of which have been shown to possess curare-like activity (1,2). This neuromuscular blocking property has prompted our study of the seeds of Egyptian-grown Erythrina lysistemon Hutchinson (Leguminosae). We were able to reisolate five previously described dienoids, namely (+)-erysodine [1], (+ )-erythristemine, (+)-erysotrine, ( + )-erythravine, and (+)-erysotrine N-oxide, all of which were readily identified through nmr and mass spectral comparisons (3). Of greater import, however, was the isolation of three novel glycosides, (+)-11 ß-methoxyglucoerysodine [31, (+)-11 ß-methoxyglucoerysovine [4], and (+ )-rhamnoerysodine [5]. The known (+ )-glucoerysodine [2] was also reisolated and characterized by nmr spectroscopy. Isomers 3 and 4 were

N-methylasimilobine was isolated as the major alkaloid from an Egyptian sample of P. RHOEAS L. Other alkaloids isolated from the same plant material were stylopine, coptisine, isocorydine and rhoeadine. Chromatography indicated the presence of at least nine other minor alkaloids.

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