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1.
A simple gas chromatography-mass spectrometry (GC-MS) method has been developed for the characterization of frankincense in archaeological samples. After trimethylsilylation of the methanolic extract, 15 triterpenoids have been found among the chemical constituents of commercial olibanum (alpha-boswellic acid, 3-O-acetyl-alpha-boswellic acid, beta-boswellic acid, 3-O-acetyl-beta-boswellic acid, alpha-amyrin, beta-amyrin, lupeol, 3-epi-beta-amyrin, 3-epi-beta-amyrin, 3-epi-lupeol, alpha-amyrenone, beta-amyrenone, lupenone, 3alpha-hydroxy-lup-20(29)-en-24-oic acid and 3-O-acetyl-hydroxy-lup-20(29)-en-24-oic acid). These compounds have been unequivocally identified by retention time and mass spectral comparison with pure standards previously isolated, for the most part, in our laboratory. Within these triterpenes, acid ones, the corresponding O-acetates, and their products of degradation were found to be characteristic of frankincense (Boswellia resin). The presence of these unusual triterpenic compounds in an archaeological resinous sample, recovered during excavations from Dahshour site (Egypt, XIIth Dynasty), enabled us to identify unambiguously frankincense resin among several other materials. Additional chromatographic peaks of this sample were assigned to broad chemical classes using retention time and mass spectra features.  相似文献   
2.
Chromatographic purification of the alcoholic extract from the aerial parts of the Saudi plant Nuxia oppositifolia (Hochst.), Benth., resulted in five isolated phenolic compounds. Two flavones, hispidulin (1) and jaceosidin (2), and the phenylethanoid glycosides, verbascoside (3), isoverbascoside (4), and conandroside (5), were identified and their chemical structures were determined by spectroscopic analyses. The insecticidal activity of compounds 1 and 2, in addition to 11 compounds isolated in a previous research (6–16), was evaluated against the Yellow Fever mosquito, Aedes aegypti. Four compounds displayed adulticidal activity with LD50 values of 2–2.3 μg/mosquito. Free radical scavenging properties of the plant extracts and compounds (1–5) were evaluated by measuring the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate radical cation (ABTS•+) scavenging activity. All compounds exhibited notable activity, compared with the positive control, l-Ascorbic acid. This study suggests that N. oppositifolia could be a promising source of secondary metabolites, some with lethal adulticidal effect against Ae. aegypti.  相似文献   
3.
The structure elucidation and 1H and 13C assignments of the new triterpenes 3beta-palmitoxy-7beta-hydroxyolean-12-ene (1) and its hydrolysis product 3beta,7beta-dihydroxyolean-12-ene (2) and 3beta-sn-glyceroyl-(1'-palmitoxy)urs-12-ene (3), isolated from the aerial parts of Cladocolea grahami (Loranthaceae), are reported.  相似文献   
4.
Three new serratanes were isolated from the nonsaponifiable fraction of western white pine (Pinus monticola Dougl.) bark. The compounds were shown to be 3β-methoxyserrat-14-ene-21α,30-diol (8a), 3β-methoxyserrat-14-ene-21α, 29-diol (9a), and 3β-methoxyserrat-14-ene-21β,30-diol (10a), by a combination of chemical, and spectral methods.  相似文献   
5.
A homologous series of alkanoic acid (C2–C5) esters of germanicol was isolated from the methanolic extract of Sarcostemma clausum, of which germanicol-3-propionate and 3-pentanoate have not been previously described in the literature. In addition, taraxasterol, multiflorenol, and bauerenol were also isolated for the first time from the genus Sarcostemma. Structures were elucidated by chemical and spectroscopic methods (NMR, IR, SM) and by comparison with literature data.Published in Khimiya Prirodnykh Soedinenii, No. 6 pp. 464–466, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date.  相似文献   
6.
The new triterpene glycoside cycloorbicoside C was isolated from the aerial parts of Astragalus orbiculatus Ledeb. (Leguminosae) and was identified as (23R,24S)-16,23;16,24-diepoxycycloartan-3,25-diol 3-O--D-xylopyranoside 25-O--D-glucopyranoside.  相似文献   
7.
There is currently a worldwide consensus and recognition of the undoubted health benefits of the so-called Mediterranean diet, with its intake being associated with a lower risk of mortality. The most important characteristics of this type of diet are based on the consumption of significant amounts of fruit, vegetables, legumes, and nuts, which provide, in addition to some active ingredients, fiber and a proportion of vegetable protein, together with extra virgin olive oil (EVOO) as the main sources of vegetable fat. Fish and meat from poultry and other small farm animals are the main sources of protein. One of the main components, as already mentioned, is EVOO, which is rich in monounsaturated fatty acids and to a lesser extent in polyunsaturated fatty acids. The intake of this type of nutrient also provides an important set of phytochemicals whose health potential is widely spread and agreed upon. These phytochemicals include significant amounts of anthocyanins, stilbenes, flavonoids, phenolic acids, and terpenes of varying complexities. Therefore, the inclusion in the diet of this type of molecules, with a proven healthy effect, provides an unquestionable preventive and/or curative activity on an important group of pathologies related to cardiovascular, infectious, and cancerous diseases, as well as those related to the metabolic syndrome. The aim of this review is therefore to shed light on the nutraceutical role of two of the main phytochemicals present in Olea europaea fruit and leaf extracts, polyphenols, and triterpenes, on healthy animal growth. Their immunomodulatory, anti-infective, antioxidant, anti-aging, and anti-carcinogenic capabilities show them to be potential nutraceuticals, providing healthy growth.  相似文献   
8.
Dendritic cells are antigen-presenting cells, which identify and process pathogens to subsequently activate specific T lymphocytes. To regulate the immune responses, DCs have to mature by the recognition of TLR ligands, TNFα or IFNγ. These ligands have been used as adjuvants to activate DCs in situ or in vitro, with toxic effects. It has been shown that some molecules affect the immune system, e.g., Masticadienonic acid (MDA) and 3α-hydroxy masticadienoic acid (3α-OH MDA) triterpenes naturally occurring in several medicinal plants, since they activate the nitric oxide synthase in macrophages and induce T lymphocyte proliferation. The DCs maturation induced by MDA or 3a-OH MDA was determined by incubating these cells with MDA or 3α-OH MDA, and their phenotype was afterwards analyzed. The results showed that only 3α-OH MDA was able to induce DCs maturation. When mice with melanoma were inoculated with DCs/3α-OH MDA, a decreased tumor growth rate was observed along with an extended cell death area within tumors compared to mice treated with DCs incubated with MDA. In conclusion, it is proposed that 3α-OH MDA may be an immunostimulant molecule. Conversely, it is proposed that MDA may be a molecule with anti-inflammatory properties.  相似文献   
9.
A series of superlipophilic or highly lipophilic semisynthetic betulin derivatives was prepared and their relative lipophilicity was measured by reversed‐phase thin‐layer chromatography (RP‐TLC) at different pH values using 1,4‐dioxane–acetate buffer mixtures as mobile phases. Cholesterol, 17β‐estradiol and pure betulin were used as the reference compounds. Linear relationships were found between RM values and 1,4‐dioxane concentrations in the mobile phases. LogP values were also calculated with computer programs ACD/LogP (ChemSketch 11.0, Advanced Chemistry Development Inc.) and ClogP (Daylight Chemical Information Systems Inc.). The empirical and theoretical data were compared, and the RM0 values correlated well with logP. Two of the synthesized betulin derivatives are reported for the first time. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
10.
Enantiospecific synthesis of ABC-ring systems of A-nor and abeo 4(3→2) tetra and pentacyclic triterpenes has been accomplished starting from the readily available monoterpene (R)-carvone. (R)-Carvone was used as the B-ring of the target molecules. A lithium-liquid ammonia mediated cyclisation of δ,?-unsaturated ester was employed for the cyclopentannulation at the C-5 and C-6 carbons of carvone and an RCM reaction was employed for the cyclohexannulation to generate the ABC-ring system of A-nor tetra and pentacyclic triterpenes. The strategy has been extended for the synthesis of the ABC-ring system of abeo 4(3→2) tetra and pentacyclic triterpenes.  相似文献   
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