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1.
JPC – Journal of Planar Chromatography – Modern TLC - A thin-layer chromatographic method with densitometric UV detection at λ = 232 nm has been developed for standardization of...  相似文献   

2.
Structures of two new diterpenoids, cembrene-A and mukulol are reported. Cembrene-A is one of the two most elementary tetraenes derivable from geranyl-geranyl pyrophosphate by C1 → C14 cyclization. Mukulol is also a cembrane derivative and is biogenetically closely related to cembrene-A.  相似文献   

3.
R.S. Prasad  Sukh Dev 《Tetrahedron》1976,32(12):1437-1441
Absolute stereochemistry of mukulol, a diterpene alcohol, is established by chemical correlation with cembrene-A and (+)-cis-piperitol. Synthesis of (+)-cis-piperitol and (?)-trans-piperitol from (+)-Δ2-carene is described. Δ2-Carene oxide on exposure to silica gel passes into cis Δ2-p-menthen-1,8-diol.  相似文献   

4.
The anti-inflammatory active fraction of the Paraguayan crude drug, "Alhucema," Lavandula latifolia Vill. afforded four compounds: coumarin (1), 7-methoxycoumarin (2), trans-phytol (3) and caryophyllene oxide (4). 1 showed a weakly inhibitory effect on carrageenin-induced paw edema in rats on topical application and 4 showed an inhibitory effect on histamine-induced contraction in guinea pig ileum.  相似文献   

5.
张梦雨  徐洋  宋冠杉  辛欣  彭缨 《色谱》2016,34(8):773-777
建立了高效液相色谱-质谱联用(HPLC-MS/MS)同时测定脑心清原料药及其片剂中原儿茶酸、金丝桃苷、山柰酚-3-O-β-D-吡喃葡萄糖苷、山柰酚-3-O-β-D-吡喃半乳糖苷、杨梅素、槲皮素、柚皮素和山柰酚8种有效成分的分析方法。以乙腈和0.1%(v/v)甲酸水溶液为流动相进行梯度洗脱,经Dikma Diamonsil C18柱分离,采用电喷雾离子源以负离子多反应监测模式进行质谱检测。结果表明,8种有效成分在线性范围内线性关系良好(r > 0.99),回收率为99.0%~102.1%,相对标准偏差为0.9%~3.3%(n=6)。该方法高效、快速、准确,为脑心清原料药浸膏及其片剂的质量标准研究提供了一定的参考。  相似文献   

6.
The importance of the interfacial rheology in determining the stability of water-in-Buchan crude oil emulsions has been demonstrated in part 1 of this series of papers (R.A. Mohammed, A.I. Bailey, P.F. Luckham and S.E. Taylor, Colloids Surfaces A: Physicochem. Eng. Aspects, 80(1993)223). In part 2, interfacial tensions of crude oil, and solutions of asphaltenes and resins in a model oil have been investigated. Surface pressure vs. area (Π—A) curves of monolayers of asphaltenes, resins and their mixtures have been established. In its dependence on the ratio of resins to asphaltenes, the pseudostatic dilatational modulus has high values for low resin-to-asphaltene ratios and low values for high resin-to-asphaltene ratios. This is expected to throw light on the cause of the enhanced stability of water-in-crude oil emulsions.  相似文献   

7.
The present study evaluates the neuroprotective effect of Brahmi against methyl mercury (MeHg) toxicity. The results demonstrated that MeHg-decreased mitochondrial viability in MTT assay and IC50 value was found to be 2.5 μg/mL. However, Brahmi at 250 μg/mL concentration effectively prevented mitochondrial damage caused by MeHg in MTT assay. Our results also demonstrated MeHg significantly inhibited catalase enzyme activity, glutathione content and increased the level of thiobarbituric acid reactive substances in mitochondrial-enriched fractions of rat brain. These alterations were prevented by preincubation with Brahmi. In addition, Brahmi reverted glutathione level to normal that was depleted by MeHg, confirming its chelating effect, one of the molecular mechanisms that underlie protection against oxidative damage. Our study also focused on total phenolic and flavonoid contents of Brahmi, and it was found to contain significant amount of phenols and flavonoids. The presence of saponins was detected by HPLC which might be responsible for neuroprotection against MeHg.  相似文献   

8.
A new cassane diterpene was isolated from Amazonian crude drug, "Acapu, " the wood of Vouacapoua americana, together with two known cassane furanoditerpenes, (+)-vouacapenic acid and (+)-methyl vouacapenate. The structure was characterized as cassa-13(14), 15-dien-19-oic acid on the basis of spectroscopic evidence.  相似文献   

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Gekko gecko, an animal used as a valued traditional Chinese medicine, has been widely used for over 2000 years. Due to localized habitat destruction, the amount of G. gecko has dramatically decreased in recent years. As a result, more and more adulterants have been detected in the traditional medicine, which has resulted in a chaotic market. Therefore, a correct identification method is badly needed. In this study, we employed a new molecular method of DNA barcoding for discriminating gecko from its adulterants. Fifty-seven specimens of gecko and its adulterants were collected as test samples. The full-barcode and mini-barcode sequences of these specimens were separately amplified and sequenced separately. Together with other published barcode sequences, we detected that the intra-specific sequence diversity was far lower than the inter-specific diversity in G. gecko and its adulterants (3% compared with 35% in full-length barcode; 4% compared with 33.5% in mini-barcode). These results showed that both the full-length and mini-barcodes were effective for identifying gecko, which suggested that the DNA barcode could be an effective and powerful tool for identifying the Chinese crude drug gecko.  相似文献   

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12.
V.D. Patil  U.R. Nayak  Sukh Dev 《Tetrahedron》1973,29(11):1595-1598
Isolation and structure elucidation of two long-chain aliphatic tetrols, now formulated as octadecan-1,2,3,4-tetrol and eicosan-1,2,3,4-tetrol, from gum-resin of Commiphora mukul, is described. There is evidence for the occurrence of nonadecan-1,2,3,4-tetrol, as well, in the resin. This is the first reported occurrence of such compounds in nature, though the closely related phytosphingosines (e.g. 2-amino-octadecan-1,3,4-triol) are well known.  相似文献   

13.
Several extracts of crude drugs were prepared and tested as penetration enhancers for the diffusion of prednisolone through mouse skin in vitro. The acetone extract of cardamon seed (Eelettaria cardamomum) was selected for further study to identify the active principles. The result showed that terpineol and acetyl terpineol are the active components in cardamon seed.  相似文献   

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15.
Ashok G. Bajaj  Sukh Dev 《Tetrahedron》1982,38(19):2949-2954
20α-hydroxy-4-pregnen-3-one (5), 20β-hydroxy-4-pregnen-3-one (6), 16β-hydroxy-4,17(20)Z-pregnadien-3-one (4) and 16α-hydroxy-4-prenen-3-one (10) have been isolated as new steroidal components of the gum-resin from Commiphora mukul. A simple procedure for the synthesis of 4 is described. Chirality at C-20, C-22 in guggulsterol-I (3) has been clarified.  相似文献   

16.
Tu-zhu-ye is a Korean crude drug for use as a diuretic but its plant source has not been identified. The present work has been attempted for identification of the original plant using specimens collected both at Seoul and Taegu, Korea, their mineral microstructures being examined after ashing the specimens by a low-temperature method with high-frequency oxygen plasma. A preliminary survey of the specimens with the naked eye suggested that the Tu-zhu-ye was near to Phyllostachys or its closely related bamboo species. Several specimens, namely, Phyllostachys heterocyclaMitf. var. pubescensOhwi, Phyllostachys nigraMunro var. henonisStapf, Phyllostachys bambusoidesSieb. et Zucc. and Bambusa multiplexRaeuschel were therefore ashed by the low-temperature method and the comparative microscopic studies with the resultant ashed tissues concluded that the “Tu-zhu-ye” from Seoul was perfectly identical with Phyllostachys nigraMunro var. henonisStapf. A further investigation is continued for the specimen from Taegu since it is different from any other specimens provided for the present work.  相似文献   

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The efficient and rapid detection of bioactive compounds in complex matrices of different origins (natural or synthetic) is a key step in the discovery of molecules with potential application in therapy. Among them, molecules able to interact with nucleic acids can represent important targets.In this study, an optical DNA biosensor, based on surface plasmon resonance (SPR) transduction, has been studied in its potential application as new analytical device for drug screening. This device was applied to the analysis of pure synthetic or natural molecules and also to some fractions obtained by chromatographic separation of an extract of Chelidonium majus L. (great celandine), a plant containing benzo[c]phenanthridinium alkaloids having intercalating properties.The ability of these molecules to interact with the double stranded nucleic acid (dsDNA) immobilised on the sensor surface has been investigated. The optical sensing relies on the SPR-based bench instrument Biacore X™ and represents an example of multiuse sensor. The results obtained demonstrate the potential application of this device for the rapid screening of bioeffective compounds. The characteristics of the biosensor offer the possibility to be coupled to chemical analysis as in hyphenated technologies.  相似文献   

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