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1.
From the aerial parts of Canscora decussata Schult (Gentianaceae), five triterpenes, viz. gluanone, canscoradione, friedelin, fridelan-3-β-ol, and β-amyrin, three sterols, viz. sitosterol, stigmasterol, and campesterol, besides liberal amount of a mixtures of n-alkanes (C27-C31) and n-alkanols (C26-C32) have been isolated. The identity of the compounds has been established by chemical transformations, spectral evidence, and by direct comparison, where possible, with authentic reference materials. Gluanone and canscoradione have not been encountered before in nature.  相似文献   

2.
The carbonyl compound, previously isolated from the stems of Mallotus paniculatus, has been proved to be 29-nor-21αH-hopane-3,22-dione. 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-dioic and 3β,28-dihydroxyurs-12-en-27-oic acids.  相似文献   

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The petrol extracts of the stems and leaves of Phyllanthus reticulatus both gave friedelin and sitosterol, and that of the former also friedelan-3β-ol, glochidonol, 21α-hydroxyfriedelan-3-one and a new compound, which was proved to be 21α-hydroxyfriedel-4(23)-en-3-one. The ethanol extract of the stems yielded betulinic acid.  相似文献   

5.
A new bark acid, isochapelieric acid (cis-chapelieric acid), chapelieric acid, friedelin, friedelan-3β-ol, canophyllal, canophyllol, friedelan-3β,28-diol, canophyllic acid and amentoflavone have been isolated and characterized from leaf extractives of Calophyllum calaba. 13CNMR spectra of methyl chapelierate and methyl isochapelierate have been recorded and interpreted. Leaf extractives of Garcinia spicata afforded an unidentified long chain carboxylic acid, friedelin, friedelan-3β-ol, sitosterol and the biflavanones GB-1, GB-1a, GB-2a and morelloflavone. Chemotaxonomic significance of the occurrence of some of the above foliar constituents in Calophyllum and Garcinia species is discussed.  相似文献   

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Epoxyparvinolide which belongs to a new class of sesquiterpenoid lactones, the secocaryophyllanolides, was isolated from Pogostemon parviflorus along with friedelin, friedelan-3-ol, phytol and sitosterol. Epoxyparvinolide was characterized as 4,5-epoxy-9,10-secocaryophyllen-9β,10-olide.  相似文献   

10.
3-Oxo-friedelan-20α-oic acid, named as maytenonic (polpunonic) acid, has been isolated along with β-amyrin and sitosterol from Gymnosporia emarginata. 1H and 13C NMR signals have been assigned for the structure. X-ray analysis of the single crystal confirmed that the carboxylic acid is α-oriented at C-20 and the D/E rings of this D:A-friedo-oleanane are in chair-chair conformation. 13C NMR data of the present compound also enabled the assignment of the C-20α- and β-methyl carbons in friedelin.  相似文献   

11.
A new tetracyclic triterpene cycloart-25-en-3β-ol (9β,19-cyclolanost-25-en-3β-ol) and cyclolaudenol, have been isolated from Euphorbia nivulia.  相似文献   

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A substantial amount (ca 18%) of the sterol found in the seeds of Cucurbita maxima had a Δ-bond and consisted of seven components. They were identified as 25(27)-dehydroporiferasterol, clerosterol, isofucosterol, stigmasterol, sitosterol, campesterol and codisterol. The C-24 configuration of each of the sterols was unequivocally established by a 1H NMR spectral comparison with authentic standards. This is the first time codisterol has been found in a higher plant and also the first time the structures and configurations of the Δ5-sterols from a Cucurbitaceae species have been clearly characterized.  相似文献   

14.
The 1500 X g supernatant of the silkworm Bombyx mori gut homogenate catalyzed the conversion of 24, 28-epoxystigmast-5-en-3β-ol(III) to cholesta-5, 24-dien-3β-ol(IV) which is a key step of stigmast-5-en-3β-ol(I) dealkylation in the insects. A structural analog 24, 28-imino-stigmast-5-en-3β-ol(VI) was a potent inhibitor of this conversion.  相似文献   

15.
Croton celtidifolius has been found to contain 1l-1-O-methyl-myo-inositol, neo-inositol and sitosterol. Structure of 1l-1-O-methyl-myo-inositol pentaacetate, elaborated by NMR decoupling technique, is described.  相似文献   

16.
The terpenoid and flavonoid constituents of the hitherto unexamined medicinal plant Bridelia ferruginea are reported. Quercetin, quercetin 3-glucoside, rutin, myricetin 3-glucoside and myricetin 3-rhamnoside were identified.  相似文献   

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From the roots of Vernonia cinerea a new natural sterol and a new aliphatic acid characterized as stigmast-5,17(20)-dien-3β-ol and 26-methylheptacosanoic acid, respectively, have been isolated together with stigmasterol and sitosterol.  相似文献   

19.
The 4-desmethylsterol fraction of the liverwort Palavicinnia lyellii is composed of 36% 24β-methylcholest-5-en-3β-ol (dihydrobrassicasterol), 16% 24α-methylcholest-5-en-3β-ol (campesterol), 33% 24α-ethylcholest-5-en-3β-ol (sitosterol) and 15% 24ξ-ethylcholesta-5,22-dien-3β-ol.  相似文献   

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