Cyclea atjehensis

Recently the leaves of another species, Cyclea atjehensis Forman, have been investigated by Shamma s group (22). It was found that the alkaloids of C. atjehensis are head-to-tail bisbenzylisoquinoline alkaloids of the curine type. Four new and novel amidic bisbenzylisoquinolines... 

V-Formylnornantenine (54), a new amidic aporphine alkaloid, has been isolated from Cyclea atjehensis. Analysis of the NMR spectrum at... 

There are two alkaloids of this series that bear a methylenedioxy group at C(6)/C(7) and are acetylated at N(2 ). These are isocuricycleatjenine (410) and isocuricycleatjine (411), two compounds that differ only by the presence of a 7-methoxy group in the former and a 7-hydroxy group in the latter. These alkaloids have only been found in Cyclea atjehensis (Menispermaceae). 

Two closely related alkaloids from this group are curicycleatjenine (400) and curicycleatjine (401), compounds that contain a methylenedioxy function at C(S)/C(6). These two alkaloids differ only in the nature of the C(12) function, whereas in the former it is methoxy group and in the latter a hydroxy group. These alkaloids have only been isolated from Cyclea atjehensis (Menispermaceae). Hayatidine (136), an alkaloid of Cissampelos pareira (Menispermaceae), is a diastereoisomer of 12 -O-methylcurine (140). (-)-Tubocurarine (143), a diastereoisomer of (+)-tubocurarine (142), has only been isolated from Chondodendron lomentosum (Menispermaceae). 

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