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1.
MUHAMMAD Naeem Ahmed KHAWAJA Ansar Yasin MUHAMMAD Nawaz Tahir IFZAN Arshad MURTAZA Madni 《结构化学》2015,34(1):26-32
Two new 1,4-disubstituted 1,2,3-triazoles-4-carboxylates were synthesized via click reaction. Compound 1a was synthesized by the interaction of 6-nitro-tetrazolo[1.5-a]-pyridine with ethyl propynoate at room temperature in the presence of Cu(OAc)2 as a catalyst and THF as solvent. Compound 1b was also synthesized by the same manner except that tert-butyl propionate, instead of ethyl propynoate, was used. The compounds were characterized by IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction analysis. Compound 1a(C10H9N5O4) crystallizes in the triclinic system, space group P1 with a = 5.0894(9), b = 8.9834(13), c = 13.089(2) ?, α= 83.041(7), β= 80.256(7), γ=87.296(8)°, V = 585.24(16)?3, Z = 2, Mr = 263.22, crystal size(mm) = 0.37 × 0.20 ×0.18,(I 2σ(I)) = 8557, 2493, 1229, Rint = 0.057. Compound 1b(C12H13N5O4) crystallizes in the monoclinic system, space group P21/c with a = 6.8854(5), b = 21.783(2), c = 9.3986(8) ?,β = 93.239(4)°, V = 1407.4(2)?3, Z = 4, Mr = 291.27, crystal size(mm) = 0.38 × 0.22 × 0.20,(I 2σ(I)) = 11842, 3172, 1866, Rint = 0.047. Antimicrobial assay results showed that the title compounds display excellent activities to different bacterial and fungal strains. 相似文献
2.
S. Chandrasekaran K. Gopal P. X. Franklin Balasubramanian Jaganatha Sivakumar Gajendra Singh Shridhar Narayanan B. Gopalan Ansar A. Khan 《Biomedical chromatography : BMC》2013,27(8):1018-1026
The present investigation describes the development and validation of a sensitive liquid chromatography–mass spectrometry/mass spectrometry (LC‐MS/MS) method for the estimation of dorsomorphin in rat plasma. A sensitive LC‐MS/MS method was developed using multiple reaction monitoring mode, with the transition of m/z (Q1/Q3) 400.2/289.3 for dorsomorphin and m/z (Q1/Q3) 306.2/236.3 for zaleplon. Chromatographic separation was achieved on a reverse phase Agilent XDB C18 column (100 × 4.6 mm, 5 µm). The mobile phase consisted of acetonitrile and 5 mm ammonium acetate buffer (pH 6.0) 90:10 v/v, at a flow rate of 0.8 mL/min. The effluence was ionized in positive ion mode by electrospray ionization (ESI) and quantitated by mass spectrometry. The retention times of dorsomorphin and internal standard were found to be 2.13 and 1.13 min, respectively. Mean extraction recovery of dorsomorphin and internal standard in rat plasma was above 80%. Dorsomorphin calibration curve in rat plasma was linear (r2 ≥ 0.99) ranging from 0.005 to 10 µg/mL. Inter‐day and intra‐day precision and accuracy were found to be within 85–115% (coefficient of variation). This method was successfully applied for evaluation of the oral pharmacokinetic profile of dorsomorphin in male Wistar rats. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
3.
Sadiq‐ur‐Rehman Bilal Ahmad Khan Muhammad Aziz Chaudhary Khawaja Ansar Yasin Saqib Ali 《Heteroatom Chemistry》2015,26(6):417-425
Di‐ and triorganotin(IV) carboxylates, RnSn(OCOC(R2)=CHR1)4–n (n = 2 and 3; R = Me, Et, n‐Bu, Ph; R1 = 3‐CH3O‐4‐OHC6H3, R2 = C6H5) were prepared by reacting the corresponding organotin(IV) chloride with the silver salt of the (E)‐3‐(4‐hydroxy‐3‐methoxyphenyl)‐2‐phenylpropenoic acid. The title compounds were investigated and characterized by elemental analysis, infrared (FT‐IR), multinuclear (1H, 13C, 119Sn) NMR, and mass spectrometry, and possible structures were proposed. The complexes and ligand acid ( HL ) have been evaluated in vitro against various bacteria and fungi. The results noticed during the biocidal activity screenings proved their in vitro biological potential. They were also tested for cytotoxicity. 相似文献
4.
Soodabeh Davaran Mohammad Sadeghinia Zahra Jamalpoor Vahideh Raeisdasteh Hokmabad Mehdi Doosti-Telgerd Ansar Karimian Zahra Sadeghinia Javad Khalilifard Akram keramt Farzad Moradikhah Ali Sadeghinia 《Electrophoresis》2020,41(12):1081-1094
Microfluidic system, or lab-on-a-chip, has grown explosively. This system has been used in research for the first time and then entered in the clinical section. Due to economic reasons, this technique has been used for screening of laboratory and clinical indices. The microfluidic system solves some difficulties accompanied by clinical and biological applications. In this review, the interpretation and analysis of some recent developments in microfluidic systems in biomedical applications with more emphasis on tissue engineering and cancer will be discussed. Moreover, we try to discuss the features and functions of microfluidic systems. 相似文献
5.
Sahar Al Akoum-Ebrik Mohamed Ansar Rahima Mouhoub Claude Vaccher Marie-Pierre Vaccher Nathalie Flouquet 《光谱学快报》2013,46(5):925-944
The enantiomeric composition and absolute configuration of 4-Amino-3-(benzo[b]furan-2-yl)-Butanoic Acids and of 4-Amino-3-(thien-2-yl)-Butanoic Acids 1 may be accurately determined by 1H and 13C nuclear magnetic resonance analysis of the corresponding derivatives 3 prepared by reaction with chiral reagents. Correlation with HPLC is signaled. 相似文献
6.
Khongsit Ansar Rajput Yudhishthir Singh Meena Sunita Sharma Rajan 《Journal of Analytical Chemistry》2022,77(3):295-300
Journal of Analytical Chemistry - Methods for the determination of mercury are described using gold nanoparticles functionalized with nitrogen containing cyclic molecules. Detection methods are... 相似文献
7.
Coating quality is affected by arc and plume instabilities during plasma spraying. In closed chamber plasma spraying, gradual drift is one of the intermediate instabilities, which is mainly due to the electrode erosion. This work focuses on the source of the gradual drift of the plasma jet and the influence on coating quality. The ambient state inside the chamber was controlled by a ventilation system and a vacuum system. The variation in the plasma jet was observed by a particle flux image device based on a CCD camera. The optical spectrum of the plasma plume was measured and analyzed through an optical spectrometer. The results indicated that the addition of hydrogen to plasma gas induced the change in the plasma jet length and width with changing rates depending on the chamber state and the ventilation power. With poor ventilation, the intensity of Hα emission was found to become gradually stronger while Hβ and Hγ were found to become weaker. On closing the chamber and retaining enough ventilation power, it was observed that the ambient gas slowly turned red. Simultaneously, the coating weight and thickness were slightly decreased meanwhile the porosity ratio was obviously increased. The red ambient gas has been proved to be able to acidify the city water with pH value decreased from 7 to 1–3. Without hydrogen, the plasma jet was found to be stable without reddening and variation, but the plasma enthalpy was unfortunately low. 相似文献
8.
Akhtar J Mehmood RF Malik MA Iqbal N O'Brien P Raftery J 《Chemical communications (Cambridge, England)》2011,47(6):1899-1901
We describe for the first time the use of a single source precursor to deposit thin films and nanocrystals of palladium selenide. 相似文献
9.
Rabia Javeed Dilshad Hussain Fahmida Jabeen Adeela Saeed Batool Fatima Muhammad Naeem Ashiq Muhammad Najam-ul-Haq 《Biomedical chromatography : BMC》2020,34(1):e4693
High-density lipoproteins (HDLs) have anti-inflammatory and antioxidant properties and are potentially cardio-protective. Defective HDL function is caused by alterations in both the proteome and lipidome of HDL particles. As potential biomarkers, the development of analytical methods is necessary for the enrichment of HDLs. Therefore, a method for selective enrichment of HDLs using immobilized metal ion affinity chromatography (IMAC) and metal oxide affinity chromatography (MOAC) is presented. SPE-based isolation of HDLs from whole serum is adopted as an alternative to traditional ultracentrifugation methods followed by SDS–PAGE. The enrichment mechanism relies on isoelectric points of lipoproteins and metal oxide. Negatively charged lipoprotein particles interact with positively charged metal oxides and IMAC affinity, which acts as a cation. Identified proteins from HDL through MALDI–MS analysis are apo AI, AII, AIV, CI, CIII, E, J, M, H, serum amyloid A and other nonapoproteins that are part of HDL particles and perform cellular functions. This serum-based proteomics approach gives insight into the functional role of HDL. HDL-associated phospholipids have also been analyzed by LDI–MS. Results suggest that the adopted analytical strategy is a feasible idea to extract lipoproteins from serum. A comparative study of healthy and diseased samples using this approach will provide valuable information in future. 相似文献
10.
Dr. Javeed Mahmood Seok‐Jin Kim Hyuk‐Jun Noh Dr. Sun‐Min Jung Ishfaq Ahmad Dr. Feng Li Jeong‐Min Seo Prof. Jong‐Beom Baek 《Angewandte Chemie (International ed. in English)》2018,57(13):3415-3420
A three‐dimensional (3D) cage‐like organic network (3D‐CON) structure synthesized by the straightforward condensation of building blocks designed with gas adsorption properties is presented. The 3D‐CON can be prepared using an easy but powerful route, which is essential for commercial scale‐up. The resulting fused aromatic 3D‐CON exhibited a high Brunauer–Emmett–Teller (BET) specific surface area of up to 2247 m2 g?1. More importantly, the 3D‐CON displayed outstanding low pressure hydrogen (H2, 2.64 wt %, 1.0 bar and 77 K), methane (CH4, 2.4 wt %, 1.0 bar and 273 K), and carbon dioxide (CO2, 26.7 wt %, 1.0 bar and 273 K) uptake with a high isosteric heat of adsorption (H2, 8.10 kJ mol?1; CH4, 18.72 kJ mol?1; CO2, 31.87 kJ mol?1). These values are among the best reported for organic networks with high thermal stability (ca. 600 °C). 相似文献