Ursolic Acid Acetate Research Articles

Allylic oxidation in triterpenes under chemical ionization conditions

The unusually abundant [M + NH 4 − 2] + ion observed in the CI(NH 3) spectra of certain triterpene carboxylic acids of the ursane and oleanane skeletons were found to be due to the allylic oxidation products, viz. Δ 11-13,28-lactone and/or Δ 11,13(18)-diene acid as seen from a CA spectral study. The CA spectra of the [M + NH 4 − 2] + ion of hederagenin diacetate ( 1) and ursolic acid acetate ( 5) and the [M + NH 4] + ion from 1, the Δ 11-13,28-lactones ( 3 and 7) and the Δ 11,13(18)-diene acid ( 4) are discussed.

ヒキオコシの根の成分

A new compound and several known compounds were isolated from the roots Rabdosia japonica (BURM.) HARA. They were a phenolic compound, triterpenoids, steroids, and fatty acids, but a diterpenoid was not found. The structure of a new compound was elucidated as hexacosyl 4-hydroxy-3-methoxycinnamate by spectroscopic analyses. The major compounds identified were ursolic acid acetate, oleanolic acid acetate, ursolic acid, β-sitosterol, β-sitosterol glucoside, and methyl palmitate. These compounds except for ursolic acid, β-sitosterol, and methyl palmitate were isolated for the first time from Rabdosia species.

Triterpenoids of the bark of Pieris japonica D. Don.

Triterpenoids in the bark of Pieris japonica D. DON were investigated. Oleanolic acid acetate, ursolic acid acetate, ursolic acid, β-sitosterol, lupeol and compound A (VI), mp 262-263°, C32H50O5, were obtained. The physical properties of VI were elucidated by infrared absorption, nuclear magnetic resonance (NMR), 13C-NMR and mass spectral studies. The structure of VI is probably 3β-acetoxy-16α-hydroxy-ursan-28, 19-olide.

Reinvestigation of the action of hydrogen peroxide on ursolic acid acetate

The action of hydrogen peroxide on ursolic acid acetate in boiling acetic acid has been reinvestigated, and the three oxidation products, designated as U I, U II and U III, have been reisolated. The structure of U I has been revised to 8a and that of U II has been established as 11a on the basis of spectral and chemical evidence. Additional spectral data are provided in support of the structure of U III ( 5a). The stereoelectronic factors responsible for the unusual stability of the epoxide function in U I towards acid-catalysed rearrangement to the 12-keto-derivative ( 9a) and the facile conversion of the latter to the enol-acetate ( 10a), compared to the normal behaviour of the structurally similar compounds, 8b and 9d of the oleanane series, have been rationalised.

Studies on the constituents of Lyonia ovalifolia sieb. et zucc. var. elliptica hand.mazz. VII. The consituents of the wood with bark. (2). Examination of the benzene soluble components

The saw dust from the trunk of Lyonia ovalifolia var. elliptica was extracted with methanol. The extract was concentrated, treated with benzene, and the benzene layer was examined by alumina column chromatography. The presence of 2-nonacosanone, taraxerone, taraxerol, β-sitosterol, and ursolic acid acetate were detected.

The Effect of Triterpenes on the Excretion of Sodium and Potassium by Rats

The acetates of ursolic acid, oleanolic acid, glycyrrhetinic acid, lupeol, and lurenol were administered subcutaneously to adrenalectomized rats and their effect on the excretion of sodium and potassium determined. Ursolic acid acetate induced significant sodium retention at 3 mg. per rat. Potassium excretion was not affected.