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101.
Kashif Maqbool Khan Lutfun Nahar Abdul Mannan Ihsan Ul-Haq Muhammad Arfan Ghazanfar Ali Khan 《Natural product research》2018,32(18):2193-2201
Trillium govanianum Wall. ex D. Don (Melanthiaceae alt. Trilliaceae), commonly known as ‘nagchhatry’ or ‘teen patra’, distributed from Pakistan to Bhutan about 2500–3800 m altitude is indigenous to Himalayas region. In folk medicine the plant has been reported for the treatment of wound healing, sepsis and in various sexual disorders. This paper reports, for the first time, to evaluate the cytotoxicity, in vitro anti-leishmanial (promastigotes) and fingerprint HPLC-photodiode array analysis of the MeOH extract of the roots of T. govanianum and its solid phase extraction fractions. Reverse phase HPLC-PDA based quantification revealed the presence of significant amount of quercetin, myrecetin and kaemferol ranging from 0.221to 0.528 μg/mg DW. MeOH extract revealed distinguishable protein kinase inhibitory activity against Streptomyces 85E strain with 18 mm bald phenotype. The remarkable toxicity profile against brine shrimps and leishmanial was manifested by MeOH extract with LC50 10 and 38.5 μg/mL, respectively. 相似文献
102.
Iridoid glycosides from Globularia davisiana 总被引:1,自引:0,他引:1
Caliş I Kirmizibekmez H Taşdemir D Ireland CM 《Chemical & pharmaceutical bulletin》2002,50(5):678-680
From the ethanolic extract of the aerial parts of Globularia davisiana, a new iridoid glycoside, davisioside (1), was isolated. Davisioside (1) comprises a rare iridoid aglycone structure with a saturated double bond between C-3 and C-4. Nine known iridoid glycosides, asperuloside (2), alpinoside (3), geniposide (4), globularin (5), globularicisin (6), 10-O-benzoylcatalpol (7), lytanthosalin (8), melampyroside (9), agnuside (10), and three known phenylethanoid glycosides, verbascoside, isoacteoside and leucosceptoside A were also isolated and characterized. The structures of the isolates were established by spectroscopic methods (one-dimensional (1D)- and two-dimensional (2D)-NMR, MS). 相似文献
103.
To convert vegetable edible oils into vanaspati ghee, nickel is used as a catalyst in the hydrogenation process. A simple and fast method for the trace level determination of nickel in ghee is reported. In this work different methods were applied for the extraction of residual nickel from ghee samples. Using toluene, benzene and carbon tetrachloride as organic solvents, an acid mixture was used for the extraction of nickel. Extracted nickel was quantified with atomic absorption and colorimetric methods. Among the organic solvents, toluene proved to be the best solvent mediating a 95% extraction of nickel from ghee samples. Nickel was extracted and determined in ten different brands of ghee and in all samples its amount was well above the permissible limit of WHO (0.2 μg/g). Other metals like lead, zinc, copper, and cadmium were also determined and their concentrations were found to be much below the WHO permissible limits. 相似文献
104.
Two new lucidin type anthraquinone glycosides, putorinoside A (1) and putorinoside B (2) were isolated from Putoria calabrica, in addition to two known anthraquinone glycosides, lucidin 3-O-beta-glucopyranoside (3) and lucidin 3-O-primeveroside (4). Based on spectroscopic data, putorinosides A and B were identified as 2-hydroxymethyl-1-methoxy-3,5,6-trihydroxyanthraquinone 3-O-beta-glucopyranoside and 2-hydroxymethyl-1-methoxy-3,6-dihydroxyanthraquinone 3-O-beta-glucopyranoside, respectively. 相似文献
105.
Nazakat Ullah 《Communications in Mathematical Physics》1986,104(4):693-695
An identity satisfied by the eigenvalues of a real-symmetric matrix and an integral representation of a determinant using Grassmann variables are used to show that the ensemble average ofS different pairs of eigenvalues of a GOE is given by (–1)
S
2–S
–1/2(S+1/2). 相似文献
106.
Spectrophotometric Determination of Prochlorperazine Maleate in Pure and Pharmaceutical Preparations
Tehseen Aman Zeeshan Majeed Asrar Ahmad Kazi Islam Ullah Khan 《Mikrochimica acta》2002,138(1-2):13-17
Prochlorperazine maleate reacts with 1-naphthylamine and sodium nitrite, after heating for 110 s at 80 °C to give an orange
red colour having maximum absorbance at 460 nm. The reaction is selective for prochlorperazine maleate with 0.01 mg/mL as
visual limit of quantitation and provides a basis for a new spectrophotometric determination. The colour reaction obeys Beer’s
law from 0.01 mg/10 mL to 0.33 mg/10 mL of prochlorperazine maleate and the relative standard deviation is 0.68%. The quantitative
assessment of tolerable amounts of other drugs is also studied.
Received September 22, 2000. Revision June 19, 2001 相似文献
107.
The principles of metal‐alkaloid ion‐pair formation and liquid‐liquid extraction are applied to the development of a sensitive and convenient atomic absorption spectrophotometery (AAS) method for the indirect determination of cocaine. In an aqueous medium of 5 M hydrochloric acid, cocaine is protonated and is associated with tetrachloro ferrate (III) anion prior to its extraction into 1,2‐dichloroethane. The critical experimental variables were identified and optimized. The method is simple and reproducible with a detection limit (DL) of 0.1 ng cm?3 cocaine in water, a relative standard deviation of 0.07 (n = 12), and the calibration graph was linear up to 50 ng cm?3 cocaine. 相似文献
108.
Caliş I Bedir E Kirmizibekmez H Ersöz T Dönmez AA Khan IA 《Natural product research》2005,19(5):493-501
In addition to rare phenylethanoid triglycosides, myricoside and its dimetylether derivative serratumoside A {3-hydroxy,4-methoxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->3)-4-O-feruloyl-beta-D-glucopyranoside}, a new phenylethanoid glycoside, myricoside-3"-O-methylether {3,4-dihydroxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->3)-4-O-feruloyl-beta-D-glucopyranoside} along with a new neolignan glucoside, (7S, 8R)-dehydroconiferyl alcohol-8-5'-dehydroconiferyl aldehyde 4-O-beta-D-glucopyranoside were isolated from the aerial parts of Phlomis oppositiflora. The structures of the new compounds were identified by means of spectroscopic (UV, IR, 1D- and 2D-NMR, and LC-ESIMS) methods. 相似文献
109.
The [3+3] cyclization of 1,3-bis-silyl enol ethers with 1,1-diacylcyclopentanes allows a convenient synthesis of spiro[5.4]decenones. Treatment of these compounds with trifluoroacetic acid (TFA) afforded a great variety of bicyclo[4.4.0]deca-1,4-dien-3-ones containing an angular alkyl group. This core structure occurs in a number of pharmacologically relevant natural products. 相似文献
110.
Mohammed A. Huneif Seham M. Alqahtani Alqahtani Abdulwahab Sultan A. Almedhesh Mater H. Mahnashi Muhammad Riaz Najm Ur-Rahman Muhammad Saeed Jan Farhat Ullah Muhammad Aasim Abdul Sadiq 《Molecules (Basel, Switzerland)》2022,27(11)
Diabetes mellitus is a metabolic disorder and is a global challenge to the current medicinal chemists and pharmacologists. This research has been designed to isolate and evaluate antidiabetic bioactives from Fragaria indica. The crude extracts, semi-purified and pure bioactives have been used in all in vitro assays. The in vitro α-glucosidase, α-amylase and DPPH free radical activities have been performed on all plant samples. The initial activities showed that ethyl acetate (Fi.EtAc) was the potent fraction in all the assays. This fraction was initially semi-purified to obtain Fi.EtAc 1–3. Among the semi-purified fractions, Fi.EtAc 2 was dominant, exhibiting potent IC50 values in all the in vitro assays. Based on the potency and availability of materials, Fi.EtAc 2 was subjected to further purification to obtain compounds 1 (2,4-dichloro-6-hydroxy-3,5-dimethoxytoluene) and 2 (2-methyl-6-(4-methylphenyl)-2-hepten-4-one). The two isolated compounds were characterized by mass and NMR analyses. The compounds 1 and 2 showed excellent inhibitions against α-glucosidase (21.45 for 1 and 15.03 for 2 μg/mL), α-amylase (17.65 and 16.56 μg/mL) and DPPH free radicals (7.62 and 14.30 μg/mL). Our study provides baseline research for the antidiabetic bioactives exploration from Fragaria indica. The bioactive compounds can be evaluated in animals-based antidiabetic activity in future. 相似文献