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1.
Choudhary MI Siddiqui ZA Musharraf SG Nawaz SA Atta-Ur-Rahman 《Natural product research》2005,19(4):311-317
The microbial transformation of prednisone (17alpha,21-dihydroxy-pregna-1,4-diene-3,11,20-trione) (1) by Cunninghamella elegans afforded two metabolites, 17alpha,21-dihydroxy-5alpha-pregn-1-ene-3,11,20-trione (2) and 17alpha,20S,21-trihydroxy-5alpha-pregn-1-ene-3,11-dione (3), while the fermentation of 1 with Fusarium lini, Rhizopus stolonifer and Curvularia lunata afforded a metabolite 1,4-pregnadiene-17alpha,20S,21-triol-3,11-dione (4). Compound 3 was found to be a new metabolite. Their structures were elucidated on the basis of spectroscopic techniques. Compound 3 showed inhibitory activity against lipoxygenase enzyme. 相似文献
2.
In order to determine the effect of airborne emission of trace elements, e.g. Br, Rb Cs, Sc and Na on roadside ecosystem, concentrations were determined in different species of plants from an urban park at Lahore. For monitoring purpose attention was paid to the leaves ofSapindus mukorossis, Alstonia scholaris andDiospyros embryopteris. Different varieties of tissues were found to have different concentration of trace elements when compared among themselves. The concentration of trace element deposition was compared with the values reported in literature. Significant pollution was observed. 相似文献
3.
Summary
Bis(cyclopentadienyl)titanium(IV) diisothiocyanate [(Cp)2-Ti(NCS)2] reacts with MCl2 (M = Cu, Pd or Pt), [CuCl(PPh3)3], [RuCl2(PPh3)3] and [RuCl2(DMSO)4] (DMSO = dimethylsulphoxide) giving solid compounds of stochiometry [(Cp)2Ti(-NCS)2MCl2] (M = Cu, Pd or Pt), [(Cp)2Ti(-NCS)2CuCl(PPh3)], [(Cp)2Ti(-NCS)2-RuCl(PPh3)2]Cl and [(Cp)2Ti(-NCS)2RuCl2(DMSO)2]. These products have been characterized by physicochemical and spectroscopic methods. 相似文献
4.
5.
Zafar Ahmed 《Tetrahedron》2005,61(8):2055-2063
A number of pulvinic acid natural products were prepared based on Suzuki cross coupling reactions of α-hydroxy-γ-alkylidenebutenolides which are readily available by cyclization of 1,3-bis-silyl enol ethers with oxalyl chloride. The formal total synthesis of pulvinic acid, atromentic acid, gomphidic acid and of 4-hydroxypulvinic acid, 4′-hydroxypulvinic acid and iso-gomphidic acid are reported. In addition, total syntheses of pinastric acid, xerocomic acid and variegatic acid were accomplished. 相似文献
6.
Saify ZS Mushtaq N Khan KM Perveen S Shah ST Abdel-Jalil RJ Fecker M Voelter W 《Chemical & pharmaceutical bulletin》2005,53(1):64-66
A new series of 4-(4'-chlorophenyl)-4-hydroxypiperidine derivatives (2-5), substituted at nitrogen, were synthesized and tested as potential analgesic compounds as well as evaluated for their effect on hypotensive activity. Results showed that all the derivatives exhibit significant analgesic activity in male Wistar rats at a dose of 50 mg/kg of body weight after intramuscular injection, when tested by thermal stimuli (tail flick test). Pethidine was used as reference drug. Compounds 2, 3 and 5 produced reduction in blood pressure in normotensive rat. 相似文献
7.
Umar Farooq Sara Khan Sadia Naz Tanveer A. Wani Syed Majid Bukhari Abullahi Tunde Aborode Sohail Anjum Shahzad Seema Zargar 《Molecules (Basel, Switzerland)》2022,27(15)
(1) Background: Achillea mellifolium belongs to a highly reputed family of medicinal plants, with plant extract being used as medicine in indigenous system. However, limited data is available regarding the exploitation of the medicinal potential of isolated pure compounds from this family; (2) Methods: A whole plant extract was partitioned into fractions and on the basis of biological activity, an ethyl acetate fraction was selected for isolation of pure compounds. Isolated compounds were characterized using different spectroscopic techniques. The compounds isolated from this study were tested for their medicinal potential using in-vitro enzyme assay, coupled with in-silico studies; (3) Results: Three new acrylic acid derivatives (1–3) have been isolated from the ethyl acetate fraction of Achillea mellifolium. The characterization of these compounds (1–3) was carried out using UV/Vis, FT-IR, 1D and 2D-NMR spectroscopy (1H-NMR, 13C-NMR, HMBC, NOESY) and mass spectrometry. These acrylic acid derivatives were further evaluated for their enzyme inhibition potential against urease from jack bean and α glucosidase from Saccharomyces cerevisiae, using both in-silico and in-vitro approaches. In-vitro studies showed that compound 3 has the highest inhibition against urease enzyme (IC50 =10.46 ± 0.03 μΜ), followed by compound 1 and compound 2 with percent inhibition and IC50 value of 16.87 ± 0.02 c and 13.71 ± 0.07 μΜ, respectively, compared to the standard (thiourea-IC50 = 21.5 ± 0.01 μΜ). The investigated IC50 value of compound 3 against the urease enzyme is two times lower compared to thiourea, suggesting that this compound is twice as active compared to the standard drug. On the other hand, all three compounds (1–3) revealed mild inhibition potential against α-glucosidase. In-silico molecular docking studies, in combination with MD simulations and free energy, calculations were also performed to rationalize their time evolved mode of interaction inside the active pocket. Binding energies were computed using a MMPBSA approach, and the role of individual residues to overall binding of the inhibitors inside the active pockets were also computed; (4) Conclusions: Together, these studies confirm the inhibitory potential of isolated acrylic acid derivatives against both urease and α-glucosidase enzymes; however, their inhibition potential is better for urease enzyme even when compared to the standard. 相似文献
8.
Dibyalochan Mohanty Ameeduzzafar Zafar Mohammed Jafar Atul Kumar Upadhyay Mohammad Akiful Haque Jeetendra Kumar Gupta Vasudha Bakshi Mohammed M. Ghoneim Sultan Alshehri Mohammed Asadullah Jahangir Mohammed Javed Ansari 《Molecules (Basel, Switzerland)》2022,27(9)
Objective: The present study aimed to develop and optimize esomeprazole loaded proniosomes (EZL-PNs) to improve bioavailability and therapeutic efficacy. Method: EZL-PNs formulation was developed by slurry method and optimized by 33 box-Bhekhen statistical design software. Span 60 (surfactant), cholesterol, EZL concentration were taken as independent variables and their effects were evaluated on vesicle size (nm), entrapment efficiency (%, EE) and drug release (%, DR). Furthermore, optimized EZL-PNs (EZL-PNs-opt) formulation was evaluated for ex vivo permeation, pharmacokinetic and ulcer protection activity. Result: The EZL-PNs-opt formulation showed 616 ± 13.21 nm of vesicle size, and 81.21 ± 2.35% of EE. EZL-PNs-opt exhibited negative zeta potential and spherical confirmed scanning electron microscopy. EZL-PNs-opt showed sustained release of EZL (95.07 ± 2.10% in 12 h) than pure EZL dispersion. The ex-vivo gut permeation result exhibited a significantly (p < 0.05) enhanced flux than pure EZL. The in vivo results revealed 4.02-fold enhancement in bioavailability and 61.65% protection in ulcer than pure EZL dispersion (43.82%). Conclusion: Our findings revealed that EZL-PNs formulation could be an alternative delivery system of EZL to enhance oral bioavailability and antiulcer activity. 相似文献
9.
Reactivity of [M2(μ‐Cl)2(cod)2] (M=Ir,Rh) and [Ru(Cl)2(cod)(CH3CN)2] with Na[H2B(bt)2]: Formation of Agostic versus Borate Complexes 下载免费PDF全文
K. Bakthavachalam K. Yuvaraj Mohammad Zafar Prof. Dr. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(48):17291-17297
Treatment of [M2(μ‐Cl)2(cod)2] (M=Ir and Rh) with Na[H2B(bt)2] (cod=1,5‐cyclooctadiene and bt=2‐mercaptobenzothiazolyl) at low temperature led to the formation of dimetallaheterocycles [(Mcod)2(bt)2], 1 and 2 ( 1 : M=Ir and 2 : M=Rh) and a borate complex [Rh(cod){κ2‐S,S′‐H2B(bt)2}], 3 . Compounds 1 and 2 are structurally characterized metal analogues of 1,5‐cyclooctadiene. Metal–metal bond distances of 3.6195(9) Å in 1 and 3.6749(9) Å in 2 are too long to consider as bonding. In an attempt to generate the Ru analogue of 1 and 2 , that is [(Rucod)2(bt)2], we have carried out the reaction of [Ru(Cl)2(cod)(CH3CN)2] with Na[H2B(bt)2]. Interestingly, the reaction yielded agostic complexes [Ru(cod)L{κ3‐H,S,S′‐H2B(bt)2}], 4 and 5 ( 4 : L=Cl; 5 : L=C7H4NS2). One of the key differences between 4 and 5 is the presence of different ancillary ligands at the metal center. The natural bond orbital (NBO) analysis of 1 and 2 shows that there is four lone pairs of electrons on each metal center with a significant amount of d character. Furthermore, the electronic structures and the bonding of these complexes have been established on the ground of quantum‐chemical calculations. All of the new compounds were characterized by IR, 1H, 11B, 13C NMR spectroscopy, and X‐ray crystallographic analysis. 相似文献
10.
Color Bricks: Building Highly Organized and Strongly Absorbing Multicomponent Arrays of Terpyridyl Perylenes on Metal Oxide Surfaces 下载免费PDF全文
Essi Sariola‐Leikas Dr. Zafar Ahmed Dr. Paola Vivo Anniina Ojanperä Dr. Kimmo Lahtonen Jesse Saari Prof. Mika Valden Prof. Helge Lemmetyinen Dr. Alexander Efimov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1501-1510
Terpyridine‐substituted perylenes containing cyclic anhydrides in the peri position were synthesized. The anhydride group served as an anchor for assembly of the terpyridyl‐crowned chromophores as monomolecular layers on metal oxide surfaces. Further coordination with Zn2+ ions allowed for layer‐by‐layer formation of supramolecular assemblies of perylene imides on the solid substrates. With properly selected anchor and linker molecules it was possible to build high quality structures of greater than ten successive layers by a simple and straightforward procedure. The prepared films were stable and had a broad spectral coverage and high absorbance. To demonstrate their potential use, the synthesized dyes were employed in solid‐state dye‐sensitized solar cells, and electron injection from the perylene antennas to titanium dioxide was observed. 相似文献