Chinese medicinal plants, alkaloids from

Chemotaxonomy of Papaveraceae and Fumariaceae, 29,1 (1986) Chinese medicinal plants, alkaloids from, 32,241 (1988)... 

Another approach to the generation of an iminium cation suitable for cyclization is the protonation of dihydropyridine derivatives. One example can be found in Scheme 48, where treatment of compound 243 with acid induced its cyclization to indoloquinolizine 244, a precursor in the first total synthesis of (i)-tangutorine 245, an alkaloid isolated from a traditional Chinese medicinal plant <2001TL6593>. 

A Papua New Guinea sponge, Pseudoceratina sp., contains the unusual alkaloids ceratamines A (1142) and B (1143), and a biogenesis involving histidine and tyrosine is proposed (1173). The fermentation broth from Aspergillus fischeri var. thermomutatus has yielded CJ-12662 (1144) and UK-88051 (1145) (1174). The former metabolite was confirmed by X-ray spectroscopy and partial synthesis. A marine-derived Streptomyces sp. produces the novel pyrrolizidine 5-chlorobohem-amine C (1146), which was shown not to be an isolation artifact (1175). The Chinese medicinal plant Huperzia serrata has furnished 2-chlorohyperzine E (1147) (1176). 

Because of their promising pharmacological properties, the carbazole-l,4-quinone alkaloids became attractive synthetic targets [30,63]. Murrayaquinone A has been isolated from the root bark of the Chinese medicinal plant Murraya euchrestifilia and shows cardiotonic activity [64], The koeniginequinones A and B have been obtained from the... 

A large number of 2-oxygenated carbazoles has been isolated from natural sources [18, 20]. Mukonidine (149) and clausine L (O-methylmukonidine) (148) have been isolated by Wu et al. from the Chinese medicinal plant C. excavata [173]. 2-Methoxy-3-methylcarbazole (146) was obtained first from the seeds of the Indian medicinal plant Murraya koenigii by Bhattacharyya and co-workers [174]. The isolation of O-methylmukonal (147) was reported by Lange et al. from M. siamen-sis [112]. Two years later, Bhattacharyya found the same compound in the roots of G. pentaphylla and renamed it glycosinine (147) [175]. Clausine V (151), a 2,7-dioxygenated carbazole alkaloid, was extracted from the root bark of C. excavata by Wu and co-workers [116]. 

Chen-Gu Ch (1957) Certain alkaloids from Chinese medicinal plants. 

The club moss Huperezia serrata has long been used in Chinese traditional medicine. An alkaloid from this plant, huperzine A (60) is one of the few drugs that appears to... 

Febrifugine was first isolated from roots of Dichroa febrifuga Lour. (Saxifragaceae), a Chinese medicinal plant traditionally used to treat malaria fevers. This alkaloid showed potent anti-Plasmodium activity, which was superior to quinine, and tmacceptable side effects, such as hepatotoxicity and severe emesis [128,129]. Its properties not only precluded its use as drug but also encouraged the synthesis of safer analogues [127]. 

The structures of sclerophytins A 17 and B 18, isolated from the soft coral Sclerophytum capitalis, were revised on basis of spectroscopic re-evaluation . Two unusual flavonoid tetrahydrofuranyl skeletons, namely tephrorin A 19 and B 20, were identified from Tephrosia purpurea . An alkaloid cartormin 21 was isolated and identified from Carthamus tinctorius, a plant used widely as a traditional Chinese medicine, <00TL1955>. 

Various species of Corydalis (fumewort, Fumariaceae) and Stephania (Jin bu huan) contain tetrahydropalmatine (1), which is the active constituent in Chinese Jin Bu Huan Anodyne tablets, sold on the Western market. The package insert suggested that Polygala chinensis is the source plant, but in reality this alkaloid comes from a species of Stephania. Both 1-tetrahydropalmatine and its racemic dl-form are used in Chinese medicine as analgesic and hypnotic agents. 

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