Maytenus chuchuhuasca

Shirota 0,Sekita S, Satake M, Morita H, Takeya K, Itokawa H. Nine regioisomeric and stereoisomeric triterpene dimers from Maytenus chuchuhuasca. Chem. Pharm. Bull. 2004 52 739-746. Shirota O, Sekita S, Satake M, Morita H, Takeya K, Itokawa H. Two new sesquiterpene pyridine alkaloids from Maytenus chuchuhuasca. Heterocycle 2004 63 1891-1896. 

Dimers are a class of compounds isolated from only seven species of Celastraceae family [8,88]. These triterpene dimers were found to be composed of one quinoid type and one aromatic type of triterpene derived from pristimerin, tingenone and / or their congeners joined together by two ether linkages formed between the two A rings or between the A and B rings. From the methylene chloride soluble portion of a methanolic extract of Maytenus chuchuhuasca, four dimeric compounds were isolated by Shirota et al. [88]. 

These structures were revised in the literature, "O. Shirota, H. Morita, K. Takeya and H. Itokawa, Revised structures of cangorosins, triterpene dimers from Maytenus ilicifolia, J. Nat. Prod. 60 (2), 111-115 (1997)". The related literatures were as follows, a) Shirota, O., Morita, H., Takeya, K. and Itokawa, H., Structures of Xuxuarines, Stereoisomeric Triterpene Dimers from Maytenus chuchuhuasca. Tetrahedron 51 (4), 1107-1120 (1995), b) Shirota, O., Morita, H., Takeya, K. and Itokawa, H., Novel Stereoisomeric Triterpene Dimers, Xuxuarines Aa and Ap, from Maytenus chuchuhuasca. Chemistry Letters 10I-I02 (1995), c) Shirota, O., Morita, H., Takeya, K. and Itokawa, H., Five New Triterpene Dimers from Mayterms chuchuhuasca, J. Nat. Prod. 60 (11), 1100-1104 (1997) and d) Shirota, O., Morita, H., Takeya, K. and Itokawa, H., New Geometric and Stereoisomeric Triterpene Dimers from Maytenus chuchuhuasca, Chem. Pharm. Bull. 46 (1), 102-106 (1998). 

Recently, Itokawa and coworkers [250] reported the isolation of five new triterpene dimers (186-190) from the South American plant xuxua Maytenus chuchuhuasca), and their structures, representative regiochemical and stereochemical isomers, were determined on the basis of spectroscopic evidence including CD spectral. Fig. (50). 

Shirota O, Sekita S, Satake M, Morita H, Takeya K, Hokawa H. Two new sesquiterpene pyridine alkaloids from Maytenus chuchuhuasca. Heterocycles 2004 63 (8) 1981. 

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