Showing papers on "Triterpene published in 1976"
TL;DR: The triterpenes of Lantana camara vary widely between taxa as discussed by the authors, and the triperpenes present in some taxa are more toxic than others, such as 3-oxolup-20(29)-en-28-oic acid.
Abstract: The triterpenes of Lantana camara vary widely between taxa. In taxa toxic to livestock 22β-angeloyloxy-3-oxoolean-12-en-28-oic acid (lantadene A) and 22β-dimethylacryloyloxy-3-oxoolean-12-en-28- oic acid (lantadene B) are present, usually as major constituents, although 3-oxolup-20(29)-en-28-oic acid (betulonic acid) predominates in the taxon Helidon White. 22β-Angeloyloxy-3β-hydroxyolean- 12-en-28-oic acid, 22β -dimethylacryloyloxy-3β -hydroxyolean-12-en-28-oic acid and 22β-hydroxy-3-oxoolean-12-en-28-oic acid, not previously known to occur in L. camara, have been isolated as well as a number of other well-known triterpenes. The non-toxic Townsville Prickly Orange contains small amounts of lantadenes A and B, and is the only taxon found to contain 228-angeloyloxy-23- hydroxy-3-oxoo1ean-12-en-28-oic acid (icterogenin). Another constituent is the new triterpene 24-hydroxy-3-oxoolean-12-en-28-oic acid. Common Pink, which is non-toxic and does not contain lantadenes A and B, is characterized by triterpene acids which have a C3, C25 oxide-bridge. It contains lantanolic acid, lantic acid, and a new acid, lantabetulic acid, considered to be 3,25-epoxy- 3a-hydroxylup-20(29)-en-28-oic acid. A mixture of the 22β-angeloyloxy and 22β-dimethylacryloyloxy derivatives of lantanolic acid from Common Pink has been converted into 22P-hydroxylantanolic acid. Wolff-Kishner reduction of 22~-hydroxy-3-oxoolean-12-en-28-oic acid gives a low yield of 22β-hydroxyolean-12-en-28-oic acid, and the major product is the C22-epimer, 22a-hydroxyolean- 12-en-28-oic acid. Corresponding products are obtained from Wolff-Kishner reduction of 22β- hydroxylantanolic acid.
80 citations
TL;DR: Arjungenin, a triterpene isolated from Terminalia arjuna, was shown to be 2α,3β,19α,23-tetrahydroxyolean-12-en-28-oic acid.
Abstract: Arjungenin, a new triterpene isolated from Terminalia arjuna, is shown to be 2α,3β,19α,23-tetrahydroxyolean-12-en-28-oic acid (1). The structures of two new triterpene glucosides, arjunglucoside I and arjunglucoside II, isolated from the same plant, were determined to be β-D-glucopyranosyl 2α,3β,19α,23-tetrahydroxyolean-12-en-28-oate (2) and β-D-glucopyranosyl arjunolate (3), respectively.
54 citations
TL;DR: A triterpene alcohol was isolated from tea (Thea sinensis, Theaceae) seed oil, and its structure was shown to be 5α-tirucalla-7,24-dien-3β-ol as discussed by the authors.
Abstract: A new triterpene alcohol is isolated from tea (Thea sinensis, Theaceae) seed oil, and its structure is shown to be 5α-tirucalla-7,24-dien-3β-ol. This triterpene alcohol is considered to be a possible biogenetic precursor to the meliane and meliacan series of oxygenated triterpenes. Gas liquid chromatographic and proton magnetic resonance spectroscopic correlations between euphane and tirucallane series triterpenes also are discussed.
30 citations
TL;DR: The methyl ethers of the tetracyclic alcohols, cycloartenol and parkeol are reported as new natural products and arundoin and miliacin occur in many species while the remaining compounds may be suitable chemotaxonomic markers.
25 citations
TL;DR: The structure of phytolaccoside B, one of the major saponin components of the roots of Phytolacca americana, has been elucidated as 3β- d -glucopyranosyljaligonic acid 30-methyl ester.
20 citations
TL;DR: Triterpene methyl ethers were isolated from the epicuticular wax of 12 species of Chionochloa and were absent from 8 species, and spontaneous multiple origins of dominant genes that control the methylation of 3 β-hydroxytriterpenes are proposed.
Abstract: Triterpene methyl ethers were isolated from the epicuticular wax of 12 species of Chionochloa and were absent from 8 species. These triterpenoids are only rarely species specific, but at the infraspecific level in some wide ranging species these are discrete biochemical races with circumscribed geographic distributions. Arundoin and miliacin, known to the common in the Gramineae, are the most frequent triterpene methyl ethers in this genus, arundoin occurring in nine species, and miliacin in six. Methyl ethers of lupeol, parkeol, cydoartenol, and β-amyrin occur in fewer species. Species such as C. pallens, C. crassiuscula, C. acicularis, and C. cheesemanii invariably synthesise triterpene methyl ethers, but in C. rigida, C. flavescens, and C. rubra there are many populations where the compounds are not produced. Spontaneous multiple origins of dominant genes that control the methylation of 3 β-hydroxytriterpenes are proposed.
20 citations
TL;DR: Aqueous hydrochloric acid hydrolysis of the mixture of thelothurins A and B, the saponins from the sea cucumber Thelonota ananas Jaeger, gave a complex mixture from which six sapogenins were isolated.
16 citations
TL;DR: A new pentacyclic triterpene acid was isolated from the arial parts of Salvia virgata and its constitution was established as 3β-hydroxy-1-oxo-olean-12-en-28-oic acid and named virgatic acid.
14 citations
TL;DR: The light petrol extracts of both the leaves and stems of M hookerianus have been found to contain friedelin, friedelan- 3β-ol and sitosterol, and the ethanol extract of the former two new triterpene acids, 3-oxours-12-ene-27,28,28-dioic and 3β, 28-dihydroxyurs -12-en-27-oic acids as discussed by the authors.
14 citations
14 citations
01 Dec 1976
TL;DR: In this paper, a dual mechanism of latex triterpene synthesis and a tentative model of latex particle formation is proposed, and three other Euphorbia species were studied for comparison and the results obtained are discussed.
Abstract: SUMMARY
α-Amyrin, esterified germanicol and β-amyrin have been identified as major constituents of E. pulcherrima latex. In freshly tapped latex only a part of the latex triterpenes were synthesized from acetate and mevalonate. By feeding 14C sugars or acetic acid to intact plants and subsequent analysis of tapped latex is synthesis of all the latex triterpenes could be demonstrated. Three' other Euphorbia species were studied for comparison and the results obtained are discussed. A dual mechanism of latex triterpene synthesis and a tentative model of latex particle formation is proposed.
TL;DR: Barrigenic acid was isolated from the fruits of Barringtonia acutangula and its structure was established as 2α,3β,19β-trihydroxyolean-12-en-23,28-dioic acid as mentioned in this paper.
TL;DR: Triterpenes from meristotropic acid, macedonic acid and lupan did not display cytotoxic effects and pentacyclic triterpene glycosides from oleanolic acid and hederagenin with free carboxyl groups at C-28 had the highest cytotoxicity activity.
TL;DR: It is suggested that the hydroxylation of the triterpene monols to the corresponding diols proceeds in the chromoplasts and the esterified form of the monols is probably the substrate for this reaction.
TL;DR: Songorosides C, G, I, M, and O have been isolated in the individual state as mentioned in this paper, and they are di-, tetra-, and pentaosides of oleanolic acid.
Abstract: By chromatography in a thin layer of silica gel, a methanolic extract of the roots ofScabiosa soongorica Schrenk. has been found to contain 17 triterpene glycosides, which have been called songorosides. Songorosides C, G, I, M, and O have been isolated in the individual state. The structures of songorosides C, G, and I have been established — they are di-, tetra-, and pentaosides of oleanolic acid.
TL;DR: In this article, the structure of hanphyllin has been determined as 3-hydroxygermacra-4,1(10),ll(13)-trien-6,12-olide.
Abstract: 6.3 Hz) and 4.87 ppm, respectively -are connected with the methylene part of the spectrum. In a study of the spectra with additions of shift reagent Eu(FOD) 3, it was found that the spin--spin coupling of the protons responsible for the last two quartets is due to one and the same methyl group, the value of AEu for which is far greater than for the other four such protons. On the basis of the results of the study of PMR spectra, the structure of hanphyllin has been determined as 3-hydroxygermacra-4,1(10),ll(13)-trien-6,12-olide.
TL;DR: The structures of songorosides M and O — a hexaoside and heptaoside of oleanolic acid, respectively — have been established and both glycosides contain gentiobiose in the acyloside moiety.
Abstract: The structures of songorosides M and O — a hexaoside and heptaoside of oleanolic acid, respectively — have been established. Both glycosides contain gentiobiose in the acyloside moiety. The glycosidic carbohydrate chains of songorosides M and G attached to the C3 hydroxyl are identical. The O-glycosidic sugar components of songorosides O and I are also identical.