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First isolation of the isoquinolinedienone alkaloid Pronuciferine (I), and of the noraporphine alkaloid Anonaine (V), besides the aporphines Nuciferine (11), Roemerine (III), and 5-Methoxy-6-hydroxy-aporphine (IV), from cotyledons of Nelumbo nucifera GAERTN. (Asiatic Lotus) is described.

Oxidation of the non-phenolic aporphines nuciferine ( 1 ), dicentrine ( 3 ), ocopodine ( 4 ) and thalicarpine ( 7 ) by iodine affords the corresponding dehydroaporphines ( 2, 5, 6 and 8 ). In contrast. iodine oxidation of non-phenolic noraporphines proceeds all the way to the oxoaporphine stage: thus. O-methylnandigerine ( 9 ), nordicentrine ( 11 ) and ovigerine ( 12 ) yield the corresponding oxoaporphines ( 10, 13 and 14 ). The phenolic aporphine N-methylnandigerine ( 19 ) is converted in low yield by iodine to the blue 10,11- o -quinone 20 ; 20 is formed as the major product of mercuric chloride oxidation of both 19 and its 10,11-isomer bulbocapnine ( 21 ). The dehydroaporphines dehydronuciferine ( 2 ) and dehydrodicentrine ( 5 ) are oxidized by oxygen at pH 6 to give the corresponding oxoaporphines ( 23 and 13 ); 2 is also rapidly oxidized to 23 by peracetic acid or by benzoyl peroxide, the benzoate ester 24 being an intermediate in the latter reaction.

The leaves and stems of Nelubmo lutea (Willd.) Pers. from Wisconsin yielded the alkaloids nuciferine, (±)-armepavine, and two apparently new alkaloids to which we have assigned structures V ((−)N-norarmepavine) and XII ((−)-N-nornuciferine).

From lotus receptacle (seed pod of Nelumbo nucifera Gaertn., four alkaloids, nuciferine (I), N-nornuciferine (VIII), oxoushinsunine (IX) and N-norarmepavine (X) were isolated. Identification of these bases were carried out by their spectral data and direct comparison with authentic samples. It is interesting that oxoushinsunine (IX), a cytotoxic alkaloid shows tumor inhibitory activity against nasopharynx carcinoma reported recently by D. Warthen et al13). The biscoclaurine (IV and V) and quaternary water soluble base (VI) only occures in the embryo. Comparison their alkaloids distribution in each part of Formosan lotus was listed in the Table 1.

The alkaloids of leaves of Nelumbo nucifera Gaertn. were examined using combined GLC-MS. The occurrence of four new alkaloids, dehydroroemerine (XII), dehydronuciferine (XI), dehydroanonaine (XIII) and N-methylisococlaurine (III) were revealed, besides the known roemerine (V), nuciferine (VI), anonaine (VII), pronuciferine (IV), N-nornuciferine (VIII), nornuciferine (IX), amepavine (I) and N-methylcoclaurine (II).