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101.
A nor-protostane, alisolide (1), a rearranged protostane, alisol O (2), and a 2,3-seco-protostane triterpene, alisol P (3), were isolated from the rhizomes of Alisma orientale, along with eight known protostane triterpenes. The structures were elucidated to be (17S)-3,11-dioxo-23-nor-protost-12-en-23(17)-olide, 3-oxo-11beta,23-dihydroxy-24,24-dimethyl-26,27-dinorprotost-13(17)-en-25-oic acid, and (20R,23S,24R)-23,24,25-trihydroxy-2,3-seco-protost-13(17)-en-3-oic acid 2,11beta-lactone, respectively, by interpretation of spectroscopic data. 相似文献
102.
The structure of 3α,11α-dihydroxylup-20(29)-ene-23,28-dioic acid, a new triterpene isolated from Schefflera octophylla, has been determined by spectroscopic methods. 相似文献
103.
Coussarea macrophylla (Mart .) Müll.Arg . (Rubiaceae) was collected in Ecuador, and the bark was extracted with AcOEt. Chromatographic separation afforded six novel 3,4‐secocycloartane and 3,4‐secodammarane triterpenes, named macrocoussaric acids A–F, together with the known metabolites secaubryenol and 3,4‐secodammara‐4(28),20,24‐triene‐3,26‐dioic acid. The structures of the new compounds were determined on the basis of their spectroscopic data. This is the first report of 3,4‐secocycloartane and 3,4‐secodammarane triterpenes occurring in a Coussarea species. Macrocoussaric acids A and B ( 2 and 3 , resp.) were found to be moderately cytotoxic against five different tumor cell lines. 相似文献
104.
Two new unsymmetric tetracyclic triterpenoids onocer-7-ene-3α,21β-diol and onocer-7-ene-3β,21α-diol together with sitosterol, δ-amyrin and δ-amyrone have been isolated from Cissus quadrangularis. The structures of the new compounds were elucidated on the basis of 1H NMR, mass spectral and chemical evidence. 相似文献
105.
Olaf Kunert Gandhe Sreekanth Gummadi Sreedhar Babu Belvotagi Venkat Rao Adavi Rao Marupaka Radhakishan Bobbala Ravi Kumar Robert Saf Achanta Venkata Narasimha Appa Rao Wolfgang Schühly 《化学与生物多样性》2009,6(8):1185-1192
We report on the chemical investigation of dikamali gum, which is the resin of Gardenia gummifera and G. lucida (Rubiaceae). Six new cycloartane triterpenes, dikamaliartanes A–F ( 1 – 6 , resp.), together with a known flavonoid ( 7 ), were isolated and identified by NMR spectroscopy. All six cycloartanes are characterized by an open A‐ring with a free COOH group at C(3). In four of them, the C‐atoms C(23)–C(27) form a 4‐methylfuran‐2‐yl moiety. Bacterial assays using Staphylococcus aureus, Candida albicans, and Mycobacteria have been carried out but did not reveal significant activity. 相似文献
106.
Nineteen reported compounds (1–19) were obtained from the dried petioles and leaves of Aquilaria sinensis (Thymelaeacea) by phytochemical methods. Their structures were determined on the basis of spectroscopic methods. Among them, compounds 6–14 and 16 were firstly obtained from the genus Aquilaria, 2 and 3 were obtained from A. sinensis for the first time. In addition, the chemotaxonomic relationships between A. sinensis and some other plants were also discussed. 相似文献
107.
Tirucallane triterpenes from the roots of Ozoroa insignis 总被引:1,自引:0,他引:1
Eight tirucallane triterpenes, methyl 3alpha,24S-dihydroxytirucalla-8,25-dien-21-oate (2), methyl 3alpha-hydroxy-24-oxotirucalla-8,25-dien-21-oate (3), methyl 3alpha-hydroxy-25,26,27-trinor-24-oxotirucall-8-en-21-oate (4), 3alpha,25-dihydroxy-24-(2-hydroxyethyl)-tirucall-8-en-21-oic acid (5), 3alpha,24S,25-trihydroxytirucall-8-en-21-oic acid (6), 3alpha,24R,25-trihydroxytirucall-8-en-21-oic acid (7), 3alpha,25-dihydroxytirucall-8-en-21-oic acid (8), and methyl 3alpha,25-dihydroxytirucall-8-en-21-oate (9), together with alpha-elemolic acid methyl ester (1), were isolated from the roots of Ozoroa insignis. Their structures were elucidated on the basis of spectroscopic evidence. 相似文献
108.
地锦草脂溶性成分研究 总被引:17,自引:0,他引:17
采用硅胶柱层析的方法,从地锦草(Euphorbia humifusa Wild.)中分离得到5个化合物,经理化鉴别及波谱分析,鉴定为羽扇豆醇(1upeol,1).cycloart-23E-en-3β,25-diol(2).cycloart-23E-en-3β,25-diol(3)、cycloart-25-ene-3β,24-diol(4)、正十六碳酸α-甘油酯(1-glycerin hexadecylate,5)。化合物1~5均为首次从该植物中分离得到。 相似文献
109.
110.
Two new dammarane-type triterpenes, ailexcelone and ailexcelol, together with ocotillone, malabaricol, epoxymalabaricol, lupeol, and sitosterol-3-O-beta-D-glucoside were isolated from the heartwood of Ailanthus excelsa. The structures of the new compounds were established on the basis of 1D- and 2D-NMR data. Ocotillone, malabaricol and epoxymalabaricol were isolated for the first time from A. excelsa. All of the isolates were tested for their antifungal activity. 相似文献