Cycloartane triterpene

Astragaloside II, a cycloartane triterpene glycoside isolated from the Egyptian Astragalus spinosus, was tested at minimum of five concentrations 10-fold dilution against a total of 60 human tumor cell lines derived from seven cancer types (lung, colon, melanoma, renal, ovarian, brain and leukemia). The results indicated that the colon cancer (SW-620) and the leukemias (CCRF-CEM, HL-60) were the most sensitive cell lines [98]... 

Abrusoside E dimethyl ester (cycloartane triterpene glycosides) Abrus precatorius (Fabaceae) [leal J Sweet... 

Cimicifuga racemosa (black bugbane, black cohosh, black snakeroot, rattleroot, rattletop, rattleweed) contains a variety of cycloartane triterpene glycosides, some of which have cytotoxic effects (3). 

Astragaloside II, a cycloartane triterpene oligoglycoside from Astragalus spinosus afforded close to 100% protection of T lymphocytes in vitro against cytopathic effects of HIV infection. The EC50of c.a. 2.5. 10 5 molar was difficult to achieve in vivo [148]. 

Recently, cycloartane triterpene glycosides (14-21) from the roots oi Astragalus melanophrurius [57] were shown to stimulate human lymphocyte proliferation in the concentration range of 0.01-10 pg/ml. At higher concentrations (100-200 pg/ml) inhibition of thymidine incorporation was observed. 

Calis I, Yiiriiker A, Tasdemir D, Wright AD, Sticher O, De Luo Y, Pezzuto JM (1997) Cycloartane triterpene glycosides from the roots of Astragalus melanophrurius. Planta Med 63 183-186... 

Esterification with a fatty acid or with ferulic acid at C-3 of triterpene alcohols exerted almost no influence on the activity as has been observed with lupane- (264/265) and cycloartane- (66/67, 72/73) type compounds and a C-3 monohydroxy triterpenoid (264/266). However, esterification at C-3 with a fatty acid reduced the inhibitory activity of some dihydroxy triterpenoids (138/139,140 202/203, 204 230/231 232/233, 234). 

A similar mass spectrum, with the same base peak, is showed by cyclocephaloside I, a cycloartane-type triterpene glycoside with a 20,25-epoxy side chain (sapogenin 27), isolated from A. microcephalus, whose structure elucidation was performed by IR, and l C NMR, FABMS and chemical methods (acetylation) [42]. The H NMR spectrum of this compound shows signals from a cyclopropane methylene (H2-19) and seven tertiary methyl groups, as reported previously. 

About 130 saponins have been described in Astragalus spp. untill now. Table (2). D-xylose (xyl), D-glucose (g c), L-rhamnose (rha), L-arabinose (ara) represent the carbohydrate components of these glycosides pentoses are more frequent then hexoses. Apiose (apio), in the furanosic form, occurs only in cycloaraloside C, named also astrailienin A [140,61]. Glucuronic acid has been found only in pentacyclic triterpene saponins (as in soyasaponins). Astragalus saponins of cycloartane series... 

Triterpenes not belonging to cycloartane series, as a-amyrin and P-amyrin, have been isolated from Aglycyphyllos [165]. From A. complanatus has been identified a new /i-coumaroyl derivative, named 11-0-/ -coumaroylnepecticyn, Fig. (3) [98,272]. 

As part of an investigation into the synthesis of tetracyclic triterpenes of the lanostane (27)-cycloartane (28) group, Packer and Whitehurst described the synthesis of the indan-2-one 29. Compound 29 has potential as a key intermediate in the synthesis of tetracyclic triterpenes, possessing the trans-CD ring junction and a carbonyl suitably positioned for introduction of the side chain at C-17. 

Curculigosaponin G (33), a new cycloartane type triterpene saponin from the rhizomes of Curculigo orchioides was shown to significantly promote proliferation of spleen lymphocytes in mice (p < 0.01) but no marked influence on antibody formation was seen (p > 0.05) [65]. 

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