Oleanane-type triterpenes

Masazumi M, Yoshiteru I, Susumu I, Junzo S. 3a-Hydroxy-oleanane-type triterpene glycosyl esters from leaves of Acanthopanax spinosus. Phytochemistry 1993 34 1599-1602. 

Dammarane derivatives. Besides the isolation of oleanane -type triterpene glycosides several new dammarane-type saponins designated... 

Triptohypol F (18) showed the presence of one double bond, two methine carbons attached to an oxygen function and one methoxy group, according to the 13C NMR spectrum. From these data and its H NMR and MS spectra, it was assumed to be an oleanane-type triterpene. The location of the double bond and the hydroxyl and methoxy groups were determined by a HMBC experiment. The stereochemistry of the hydroxyl and methoxy groups were determined by a NOESY spectrum. According to these data the structure of (18) was established as showed above. 

A number of non-proteinaceous substances of plant origin are known that induce or inhibit the sensation of sweetness. Sweetness inducers and enhancers from plants include cynarin, chlorogenic acid, caffeic acid, and arabinogalactin (larch gum) (33). A synthetic compound, 2-(4-methoxyphenoxy)propanoic acid, which is also a constituent of roasted coffee beans, is currently on the market as a sweetness inhibitor (33). Several oleanane-type triterpene esters with sweetness-inhibitory activity occur in Gynmema sylvestre leaves (33,116,117), with dammarane-type saponins with similar effects having been reported recently from the leaves of Hovenia dulcis Thunb. (Rhamnaceae) (118) and Ziziphusjujuba Mill. (Rhamnaceae) (33,119,120). 

Matsuda H, Morikawa T, Ueda H, Yoshikawa M (2001) Medical foodstuffs. XXVII. Saponin constitutes of gotu kola(2) structures of new ursane-and oleanane-type triterpene oligogly-cosidase, centell. Chem Pharm Bull 49 1368-1371... 

Morikawa T, Miyake S, Miki Y, Ninomiya K, Yoshikawa M, Muraoka O (2012) Quantitative analysis of acylated oleanane-type triterpene saponins, chakasaponins I-III and florathea-saponins A-F, in the flower buds of Camellia sinensis from different regional origins. J Nat Med 66 608... 

Yoshikawa M, Monkawa T, Nakamura S et til (2(X)7) Bioactive saponins and glycosides. XXV.l) Acylated oleanane-type triterpene saponins from the seeds of tea plant (Camellia sinensis). Chem Pharm Bidl 55 57-63... 

Glycyrrhizin has been found to concentrate in the woody parts of the thickened root and stolon of G. glabra. Betulinic acid and soya-saponins have been previously reported from G. glabra cell cultures. Recently, soyasapo-nins (oleanane-type triterpene glycosides) have been reported in all parts of the intact plant, especially the seeds and young roots, particularly rootlets. ... 

Oleanane type and migrated oleanane type triterpenes appear to be restricted to some species of Polypodium [P, niponicum, P,formo-sanum 365) and P. amamianum 329)] indicating that these three ferns are closely related to each other. 

Marsileagenin A (750) which is a hexahydroxylated oleanane type triterpene is a major sapogenol of the saponins obtained from Marsilea-minuata (Marsileaceae) 409), Such highly oxidized triterpenes are quite unusual in ferns though they occur frequently in seed plants. 

---