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61.
Three new seco-ursadiene triterpenoids 13 together with 11 known compounds were isolated from Salvia syriaca of Jordanian origin. The compounds were identified by using NMR spectroscopy including extensive 2D NMR experiments and mass spectrometry. The structure of compound 3 was confirmed by X-ray crystallography, and the information thus obtained was used to confirm the stereochemistry of compounds 1 and 2. This is the second report of 17,22-seco-17(28),12-ursadien-22-oic acids.  相似文献   
62.
Two novel constituents were isolated from the roots of Chinese medicinal herbs, Salvia miltiorrhiza. Their structures were determined by spectroscopic technique. The compounds were named 13,14-dihydroxy-15-methyl-benzo[2,3-a]-7,7-dimethyl-12-oxa-tricyclo[4,4,21.4,0]dodecane(1) and 16-methyl-tropono[2,3-c]-7,7-dimethyl-12-oxa-tricyclo[4,4,21.4,0]dodecane(2).  相似文献   
63.
In this paper the variation in the quantity and quality of the essential oil of Salvia officinalis during its life cycle stages is reported. The oils were obtained by hydrodistillation of air-dried samples. The yield of essential oil (w/w %) in different stages was in the order: floral budding (0.9%) > vegetative (0.7%) > flowering (0.5%) > immature fruit (0.4%) > ripen fruit (0.2%). The essential oils were analyzed by GC and GC-MS. In total, 36, 41, 40, 38, and 41 constituents were identified and quantified in the subsequent stages, respectively. Oxygenated monoterpenes were the main group of compounds in the fruiting set (56.9%), vegetative (48.5%), flowering (47.7%), and floral budding (45.3%) stage. 1,8-cineole as one of the major constituents of all samples was lower in the vegetative stage and gradually increased in subsequent harvesting times to reach a maximum in flowering and then decreased in the fruiting set. In contrast, the globulol content was higher in the first stage and decreased drastically during fruit maturation. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 16–19, January–February, 2006.  相似文献   
64.
The component composition of essential oils produced by steam distillation from flower heads, leaves, and stems of Salvia anatolica (Lamiaceae), a recently described new species endemic from Turkey, was studied by GC/FID and GC/MS. A total of 127 volatile components representing 96% of the oil was identified in essential oil from flower heads and leaves. It was found that the principal oil components of flower heads and leaves were α-pinene (10.9%), β-pinene (6.7%), α-copaene (6.3%), heptacosane (6.2%), and hexadecanoic acid (5.0%). A total of 109 volatile compounds representing 87.9% of the oil was characterized in essential oil isolated from stems. The principal oil components of stems were identified as hexadecanoic acid (27.2%), tetradecanoic acid (15.2%), dodecanoic acid (5.5%), and α-copaene (5.0%). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 552–555, November–December, 2007.  相似文献   
65.
采用绿色合成方法,将鼠尾草提取物用作还原和封端剂合成氧化镍纳米颗粒(NiO NPs)。此外,使用各种前驱体合成了NiO NPs,并使用扫描电子显微镜对其形貌进行了分析。利用傅里叶变换红外光谱和粉末X射线衍射(PXRD)对NiO NPs的结构进行了表征,使用振动样品磁强计测量了它们的磁性。PXRD研究表明,所有合成的NiO NPs都表现出具有高结晶度的面心立方相,并且形成了具有高纯度相的NiO。磁化研究结果表明,3种镍盐(乙酸盐、氯化物和硫酸盐)前驱体合成的NiO NPs分别表现出超顺磁、软铁磁和顺磁行为。  相似文献   
66.
The plants examined in this study have previous biological activity reports indicating the possibility of found activity against herpes and cancer cell. The aim of this contribution was to carry out a screening of Juglans mollis (Juglandaceae), Persea americana (Lauraceae), Hamelia patens (Rubiaceae), Salvia texana (Lamiaceae), Salvia ballotaeflora (Lamiaceae), Ceanothus coeruleus (Rhamnaceae), Chrysactinia mexicana (Asteraceae) y Clematis drummondii (Ranunculaceae), against HeLa cells, VHS-1 and VHS-2. The method MTT was used to determine the 50% cytotoxic concentration (CC50), in Vero and HeLa cell lines. To determine the 50% inhibitory concentration (IC50) against herpes, the plaque reduction method was used. Results showed that none of the plants exhibited activity against HeLa cells. About antiherpetic activity, J. mollis and S. ballotaeflora extracts present antiherpetic activity in terms of their SI, increasingly interest for further studies on the isolation of compounds with antiherpetic activity and about the mechanisms of action that produce this activity.  相似文献   
67.
Two cyclolanostane-type saponins, astragalosides I and II, were first identified by TLC-MS/MS in the ethyl acetate extract of the roots of Astragalus membranaceus Bge var. mongholicus (Bge.) Hsiao without chemical reference substances. They were then isolated by high-speed counter-current chromatography with a two-step two-phase solvent system of ethyl acetate-2-propanol-water (5:1:5, 50:1:50, v/v/v). The quantities of astragalosides I and II isolated from 1 g of the crude extract were 30.2 mg and 16.5 mg, respectively. Their purities were found to be over 95% by HPLC-ELSD analysis. Their chemical structures were confirmed by 1H and 13C nuclear magnetic resonance analysis.  相似文献   
68.
This review summarizes the recent advances in the chemical analysis of Danshen and its finished products, including the introduction of the identified bioactive components, analytical methods for quantitative determination of target analytes and fingerprinting authentication, quality criteria of Danshen crude herb and its preparations, as well as the pharmacokinetic and pharmacodynamic studies on the active components of Danshen and its finished products. Danshen contains mainly two types of constituents, the hydrophilic depsides and lipophilic diterpenoidal quinones and both of them are responsible for the pharmacological activities of Danshen. In order to monitor simultaneously both types of components which have different physicochemical properties, numerous analytical methods have been reported using various chromatographic and spectrophotometric technologies. In this review, 110 papers on analysis of Danshen are discussed, various analytical methods and their chromatographic conditions are briefly described and their advantages/disadvantages are compared. For obtaining a quick, accurate and applicable analytical approach for quality evaluation and establishing a harmonized criteria of Danshen and its finished products, the authors’ suggestion and opinions are given, including the reasonable selection of marker compounds with high concentration and commercial availability, a simple sample preparation procedure with high recoveries of both the hydrophilic phenols and lipophilic tanshinones, and an optimized chromatographic condition with ideal resolutions of all the target components. The chemical degradation and transformation of the predominant constituent salvianolic acid B in Danshen during processing and manufacturing are also emphasized in order to assure the quality consistency of Danshen containing products.  相似文献   
69.
新疆骆驼蓬属药用植物种类、生长环境与分布调查   总被引:2,自引:0,他引:2  
对新疆骆驼蓬属药用植物的种类、生长环境和分布进行了调查。通过野外实地考察和采样,制作植物标本,并测定和采集生长地的海拔高度、经度、纬度等地理参数和年平均气温、年降水量等气象参数。结果表明,骆驼蓬在全疆各地均有分布;骆驼蒿仅在哈密地区有少量分布,并与骆驼蓬混生,新疆境内未见有多裂骆驼蓬生长。可见骆驼蓬属耐干旱植物,新疆资源丰富,具有药用、绿化和水土保持等作用。  相似文献   
70.
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