Stephania abyssinica

Stephania abyssinica Walp. Metaphanine C19H23NOs(345) 233 -21° (CHC13) 14... 

During a search for physiologically active compounds in South African plants, a new hasubanan ester acetal alkaloid, methylstephavanine (6), was isolated from Stephania abyssinica (19). The H-NMR spectrum of the new alkaloid 6 exhibited signals for one methylenedioxy, one N-methyl, and four methoxyl groups (19) (Table II). Its mass spectrum revealed the most abundant ion peak at m/z 229, indicating a close resemblance to the known hasubanan alkaloid, stephavanine (18). 

Dihydroepistephamiersine 6-acetate (7) was isolated from Stephania abyssinica as a homogeneous oil. The UV spectrum showed an absorption maximum at 286 nm, and the IR spectrum exhibited a band corresponding to an aliphatic ester carbonyl group at 1725 cm-1 (20). The H-NMR data are summarized in Table II. In chemical investigations, hydrolysis of 7 with barium methoxide gave an alcohol identical with 6-dihydroepistephamiersine (17), which on further treatment with mineral acid gave the known alkaloid, stephasunoline (17). Thus structure 7 was proposed for 6-dihydroepistephamiersine 6-acetate (20). 

P. pseudo-orientale P. radicatum P. syriacum Stephania abyssinica S. delovayi S. japonica... 

About a year after these findings, an orange-colored oxoaporphine was obtained from Stephania abyssinica Walp. (Menispermaceae) it was at first believed that this compound was not lanuginosine since the NMR spectrum, appeared to be different (33). The structure of the 8. abyssinica base was proved conclusively to correspond to 1,2-methylene-dioxy-9-methoxyoxoaporphine not only by a detailed analysis of its NMR spectrum, but also through its reduction with zinc in hydrochloric acid to (+ )-xylopine, i.e., ( + )-l,2-methylenedioxy-9-methoxy-noraporphine, which was further acetylated to ( )-A-acetylxylopine... 

Carococculine, a new sinomenine-type alkaloid isolated from the steins and leaves of Cocculus carolinus, has been assigned structure (76). Sinoacutine and pallidine were obtained, together with berberine and other alkaloids, from Corydalis koidzumiana. Rhigiocarya racemifera produces one major alkaloid, which has been identified as O-methylflavinantine. " A new alkaloid isolated from Stephania abyssinica has been shown to be the dimethyl ether (77 R = Me) of stephavanine (77 R = H). Hydrolysis of each gave the alcohol stephine (cf. Vol. No... 

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