Showing papers on "Triterpene published in 1983"
TL;DR: From the leaves of Enkianthus cernuus forma rubens, a triterpene, 6β-hydroxyursolic acid, was isolated together with several known compounds as discussed by the authors.
62 citations
TL;DR: It was observed that both cycloartenol and 24-methylenecycloartanol in combination with soysterol greatly reduced the plasma cholesterol and enhanced cholesterol excretion, which suggests that the hypocholesterolemic activity of dietary vegetable oils may account for not only their fatty acid compositions and sterol contents but also the synergistic hypocholesterol effect of triterpene alcohols.
Abstract: To identify the synergistic hypocholesterolemic substance found in soybean oil unsaponifiable matter, rats were fed diets containing various fractions of the unsaponifiable matter prepared by silicic acid column chromatography. The plasma cholesterol level of the group fed the alcohol fraction, which mainly consisted of triterpene alcohols, was significantly lower and the effect was synergistic with soysterol. So the effect of cycloartenol and 24-methylenecycloartanol, which are main constituents of triterpene alcohols in soybean oil unsaponifiable matter, was investigated. Both compounds were prepared from gamma-oryzanol (ferulate) and were added (0.05%) respectively to the experimental diet containing 0.5% cholesterol and 1% soysterol. It was observed that both cycloartenol and 24-methylenecycloartanol in combination with soysterol greatly reduced the plasma cholesterol and enhanced cholesterol excretion. This suggests that the hypocholesterolemic activity of dietary vegetable oils may account for not only their fatty acid compositions and sterol contents but also the synergistic hypocholesterolemic effect of triterpene alcohols.
48 citations
45 citations
TL;DR: The observed selectivity of precursor utilization as well as the observed rates for product formation indicate separate sites for triterpenol and triterpene ester synthesis and that one is not precursor for the other.
34 citations
TL;DR: 10α-cucurbita-5,24-dien-3β-ol, the simplest tetracyclic triterpene with a cucurbitane skeleton, was transformed into cucurbitsacin C in Cucumis sativus seedlings, the first time it has been demonstrated to operate in plant tissues.
29 citations
TL;DR: The known triterpenes ursonic acid, oleanonic acid, ursolic acid and oleanolic acid occur in Lantana tiliaefolia Cham, together with a new triterpene, 24hydroxy-3-oxours-12-en-28-oic acid as discussed by the authors.
Abstract: The known triterpenes ursonic acid, oleanonic acid, ursolic acid, oleanolic acid and 24-hydroxy-3-oxoolean-12-en-28-oic acid occur in Lantana tiliaefolia Cham., together with a new triterpene,24-hydroxy-3-oxours-12-en-28-oic acid. A detailed 13C n.m.r. study has been made of a number of olean-12-enes and urs-12-enes, and the 1H n.m.r. signals from the secondary methyl groups in urs-12-enes have been investigated. N.m.r. evidence shows significant conformational differences in ring A between a number of 3-oxo derivatives that differ in their ring A substituents. Methyl ursonate and methyl oleanonate have been separated on columns of Spherosorb A5Y alumina.
27 citations
TL;DR: In addition to the known triterpene motiol, hopenol-b (hop-22(29)-en-3β-ol) was isolated from the whole herb of Euphorbia supina, where it has not been found previously in nature.
24 citations
TL;DR: The structure of a new tetracyclic triterpene isolated from the flowers of Musa paradisiaca was determined as (24 R )-4α,14α,24-trimethyl-5α-cholesta-8,25(27)-dien-3β-ol.
21 citations
TL;DR: Two diterpene glucosides, pieroside B and grayanoside B, and two new triterpenes, 2α,3α,24-trihydroxy, were isolated from Rhododendron japonicum.
21 citations
TL;DR: A triterpenoid, characterized as 3β-hydroxylup-20(29)-en-27-oic acid, has been isolated from the roots of Hyptis suaveolens in additi as mentioned in this paper.
21 citations
TL;DR: A new triterpene, 3-oxo-6β-hydroxyolean-18-en-28-oic acid, was isolated from Orthopterygium huancuy.
TL;DR: The structure of a new natural phenolic (9+8)-24-nor-D:A-friedo-oleanan triterpene isolated from Kokoona zeylanica has been established as 23-oxo-isopristimerin III as discussed by the authors.
TL;DR: In this article, a mixture of 4(23)-saturated seco-ring-A triterpene acid methyl esters was isolated from the wax of old leaves of Hoya lacunosa.
TL;DR: The pentacyclic triterpene acids ursolic acid, oleanolic acid and micromeric acid have been isolated from several Salvia and Teucrium species as discussed by the authors.
Journal Article•
Journal Article•
TL;DR: Possible involvement of glycosylated and sulfated forms of sterols in development of resistance in the cell membranes and tissues of trepangs to their own glycosides is discussed.
Abstract: Interaction of stichoposide A, a triterpene glycoside and trepang sterols in solution was studied With the use of liposomes the binding of the glycoside and its effect on the ion permeability of the lipid membranes of different sterol composition were also studied It was shown that the membrane activity of the glycoside was defined by the level of its affinity to the sterol receptor It decreased in the following order: cholesterol, total fraction of delta 5-sterols, total fraction of delta 7-sterols, delta 7-sterol xylosides and delta 5-sterol sulfates Possible involvement of glycosylated and sulfated forms of sterols in development of resistance in the cell membranes and tissues of trepangs to their own glycosides is discussed
TL;DR: In this article, the holothurians were extracted with hot ethanol, and the extract was concentrated in vacuum and was then lyophilized, where the residue was dissolved in water and chromatographed on columns with the polytetrafluoroethylene powder Polikhrom-i (water-50% ethanol) and then with silica gel (chloroform--ethanol-water (100:100:17) system.
Abstract: The holothurians were extracted with hot ethanol, and the extract was concentrated in vacuum and was then lyophilized. The lyophilizate was extracted at the boil with chloroform-methanol (i:i), and the extract was evaporated and filtered through silica gel in the chloroform-ethanol-water (100:100:17) system. The filtrate was evaporated, and the residue was dissolved in water and chromatographed on columns with the polytetrafluoroethylene powder Polikhrom-i (water--50% ethanol) and then with silica gel (chloroform--ethanol~ater (i00:i00: 17)). This gave the total glycosides, by chromatography of which on silica gel in the chloroform-methanol~ater (75:25:1) system we isolated the main component of the fraction, which we have called psolusoside A (I), mp 208-211°C (from ethanol), [a]D5 --73 ° , (c 0.01; pyridine).
TL;DR: From the lichen Pseudoparmelia texana the triterpene 3β-acetoxyhopan-1β,22-diol has been isolated and its structure elucidated.
TL;DR: A new glycoside of the cycloartane series, askendoside C, has been isolated from the roots of the plant Astragalus taschkendicus B., and its structure has been established on the basis of chemical transformations and spectral characteristics as mentioned in this paper.
Abstract: A new glycoside of the cycloartane series — askendoside C — has been isolated from the roots of the plantAstragalus taschkendicus Bge., and its structure has been established on the basis of chemical transformations and spectral characteristics as 24R-cycloartane-3β,6α,16β,24,25-pentaol 3-[0-α-L-arabinopyranosyl-(1→2)-β-D-xylopyranoside].
TL;DR: A triglycoside of the cycloartane series has been isolated from the roots of Astragalus sieversianus Pall; it is cyclosiversigenin 6-0-β-D-glucopyranoside 3-0-[0-α-L-rhamnopyranoyl-(1 → 2)-β-d-xylopyraniumide] as discussed by the authors.
Abstract: A new triglycoside of the cycloartane series has been isolated from the roots ofAstragalus sieversianus Pall.; it is cyclosiversigenin 6-0-β-D-glucopyranoside 3-0-[0-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranoside].
TL;DR: The new glycoside of the cycloartane series has been isolated from the roots of Astragalus sieversianus Pall. and has been shown to be cyclosiversignein 3-O-[O-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranoide]-6-O-β-d-xynide as discussed by the authors.
Abstract: The new glycoside of the cycloartane series has been isolated from the roots ofAstragalus sieversianus Pall. and has been shown to be cyclosiversignein 3-O-[O-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranoside]-6-O-β-D-xylopyranoside.
TL;DR: The benzene extract of the inner stem bark of Kokoona zeylanica Thwaites (Celastraceae) contains twelve D : A-friedo-oleananes of which nine are new as discussed by the authors.
Abstract: The benzene extract of the inner stem bark of Kokoona zeylanica Thwaites (Celastraceae) contains twelve D : A-friedo-oleananes of which nine are new. The new triterpenes have been classified under three series; kokoonol (3,27-dioxy and 3,21,27-trioxy), zeylanol (3,6-dioxy and 3,6,21-trioxy), and kokzeylanol (3,6,27-trioxy and 3,6,21,27-tetraoxy). Six of these triterpenes belonging to the kokoonol and zeylanol series have been identified as 27-hydroxy-D : A-friedo-oleanan-3-one (4)(kokoonol), 27-hydroxy-D : A-friedo-oleanane-3,21-dione (5)(kokoononol), 21α,27-dihydroxy-D : A-friedo-oleanan-3-one (6)(kokoondiol), 6β-hydroxy-D : A-friedo-oleanan-3-one (21)(zeylanol), 6β-hydroxy-D : A-friedo-oleanane-3,21-dione (22)(zeylanonol) and 6β,21β-dihydroxy-D : A-friedo-oleanan-3-one (23)(zeylandiol), by spectroscopic methods and chemical interconversions. The biosynthetic significance of 6-hydroxy-D : A-friedo-oleananes is discussed.
TL;DR: In this article, a triterpene saponin from leaves of Quercus ilex L was identified as the α-Dglucopyranosyl ester 3 of the 2α,3β,19α,23-tetrahydroxy-12-ursen-28-oic acid.
TL;DR: In this paper, the triterpene alcohols lanosterol and 24-methylenelanost-8-en-3β-ol were identified from the leaves of Symphoricarpus albus.
TL;DR: A triterpene hexaoside, stichoposide E, was isolated from an ethanolic extract of the holothurian Stichopus chloronotus by column chromatography on silica gel.
Abstract: A new triterpene hexaoside — stichoposide E — has been isolated from an ethanolic extract of the holothurianStichopus chloronotus by column chromatography on silica gel. Its complete structure has been determined as 23 (S)-acetoxy-3β-{[O-methyl-β-D-glucopyranosyl)-(1 → 3)-O-β-D-glucopyranosyl-(1 → 4)-O-β-D-xylopyranosyl-(1 → 2)]-[O-(3-O-methyl-β-D-glucopyranosyl)-(1 → 3)-O-β-D-glucopyranosyl-(1 → 4)]-β-D-xylopyranosyloxy∼ holost-7-ene.
TL;DR: In the presence of phenylenediamines-1,4 ou de benzoquinone diimines- 1,4 substituees as mentioned in this paper, the photochimique des squalane, squalene, and tetraline was obtained.
Abstract: Oxydation photochimique des squalane, squalene et tetraline en presence de phenylenediamines-1,4 ou de benzoquinone diimines-1,4 substituees
TL;DR: Astragalus galegiformis L. has yielded a new isoprenoid cyclogalegigenin this article, the structure of which has been established on the basis of chemical transformations and spectral characteristics as 20R,24S-epoxycycloartane-3β,6α,16β,25-tetraol.
Abstract: The flowers of the plantAstragalus galegiformis L. have yielded a new isoprenoid — cyclogalegigenin — the structure of which has been established on the basis of chemical transformations and spectral characteristics as 20R,24S-epoxycycloartane-3β,6α,16β,25-tetraol.