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71.
Salimuzzaman Siddiqui S.Imtiaz Haider S.Salman Ahmad B.S. Siddiqui 《Tetrahedron》1985,41(20):4577-4580
A new dihydroindole alkaloid sandwicolidine has been isolated from Rauwolfia serpentina and its structure elucidated through chemical and spectroscopic studies. 相似文献
72.
Several dissimilar types of tin oxide microstructures including bipyramids, cubes, and wires synthesized effectively by means of a simple approach were investigated using X-ray diffraction (XRD), thermogravimetry/differential thermometric analysis (TG-DTA), and X-ray photoelectron spectroscopy (XPS). A possible growth mechanism is proposed using the results of these studies. The texture coefficient values of all the structures, indexed to a tetragonal lattice, exhibit amazing variation in the preferred orientation with respect to their shapes. Although XPS data indicate that wires and cubes have a strong SnO(2) type signal, bipyramids interestingly exhibit both SnO and SnO(2) signals and a correlation of the binding energy helps in understanding the growth kinetics of such submicron structures. The results suggest that the bipyramids are formed because of the vapor-solid process (VS) while wires and cubes are formed by the vapor-liquid-solid (VLS) progression. 相似文献
73.
Liaqat Ali Imtiaz Hussain Tania Shamim Rizvi Abdul Latif Khan Shaukat Shujah Jawahar Mohammed Salim Al‐Sahi Ahmed Al‐Harrasi Javid Hussain 《Helvetica chimica acta》2015,98(10):1462-1465
A new trihydroxy sesquiterpene, rel‐(1R,4aR,5S,6S,7S,8aR)‐decahydro‐6,8a‐dimethyl‐5‐(propan‐2‐yl)naphthalene‐1,6,7‐triol ( 1 ), has been isolated as a result of the phytochemical investigation on the CH2Cl2 extract of Teucrium mascatense. The structure elucidation of the new constituent was carried out by the combined use of 1D‐ (1H‐ and 13C‐NMR) and 2D‐NMR (HMBC and HSQC) spectroscopic analysis, along with mass spectrometric techniques. In addition to the new constituent 1 , the known metabolite 2 , previously isolated from Crataegus pinnatifida, was also identified. 相似文献
74.
Faisal Usman Hamid Saeed Shah Sumera Zaib Sirikhwan Manee Jahanzeb Mudassir Ajmal Khan Gaber El-Saber Batiha Khamael M. Abualnaja Dalal Alhashmialameer Imtiaz Khan 《Molecules (Basel, Switzerland)》2021,26(21)
Type 2 diabetes mellitus has been a major health issue with increasing morbidity and mortality due to macrovascular and microvascular complications. The urgent need for improved methods to control hyperglycemic complications reiterates the development of innovative preventive and therapeutic treatment strategies. In this perspective, xanthone compounds in the pericarp of the mangosteen fruit, especially α-mangostin (MGN), have been recognized to restore damaged pancreatic β-cells for optimal insulin release. Therefore, taking advantage of the robust use of nanotechnology for targeted drug delivery, we herein report the preparation of MGN loaded nanosponges for anti-diabetic therapeutic applications. The nanosponges were prepared by quasi-emulsion solvent evaporation method. Physico-chemical characterization of formulated nanosponges with satisfactory outcomes was performed with Fourier transform infra-red (FTIR) spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Zeta potential, hydrodynamic diameter, entrapment efficiency, drug release properties, and stability studies at stress conditions were also tested. Molecular docking analysis revealed significant interactions of α-glucosidase and MGN in a protein-ligand complex. The maximum inhibition by nanosponges against α-glucosidase was observed to be 0.9352 ± 0.0856 µM, 3.11-fold higher than acarbose. In vivo studies were conducted on diabetic rats and plasma glucose levels were estimated by HPLC. Collectively, our findings suggest that MGN-loaded nanosponges may be beneficial in the treatment of diabetes since they prolong the antidiabetic response in plasma and improve patient compliance by slowly releasing MGN and requiring less frequent doses, respectively. 相似文献
75.
Qureshi Umair Imtiaz Beenish Jamal Yousuf 《Journal of Thermal Analysis and Calorimetry》2020,140(4):1745-1758
Journal of Thermal Analysis and Calorimetry - With rapid urbanization and industrialization, cheap energy supply from fossil fuels has become a problem of great extent, due to the rising fuel... 相似文献
76.
Sr2IrO4 is a weak ferromagnet where the spin arrangement is canted anti-ferromagnetic (AF). Moreover, the spin-structure coupling plays an important role in magnetic behavior of Sr2IrO4. In this concern the magnetization under zero applied field i.e. spontaneous magnetization would be interesting to study and would give insight into the novel magnetic behavior of Sr2IrO4. Sophisticated techniques like neutron diffraction, μSR etc has been used to understand the magnetic behavior of Sr2IrO4 under zero applied field. To understand the magnetic behavior we have performed field and temperature dependent magnetization study. The measured field and temperature dependent magnetic data is analyzed rigorously. We have attempted to understand the temperature dependance of spontaneous magnetization, remanent magnetization and coercive force. We observe that the spontaneous magnetization extracted from Arrott plot shows that the Sr2IrO4 is not an ideal ferromagnet. The temperature dependent coercive field follows Guant's model of strong domain wall pinning. Our investigation explicit the temperature dependence of various magnetic properties shows the magnetic transitions from paramagnetic to ferromagnetic phase with around 225 K and a low temperature evolution of magnetic moment around K. 相似文献
77.
Usman Ghani Shah Hussain Maria Imtiaz Shahid Ali Khan 《Journal of Saudi Chemical Society》2021,25(3):101198
In the present study, the role of calcination of a low iron lateritic clay sample was investigated to synthesize the geopolymer. The analyses like X-ray fluorescence (XRF) spectroscopy for chemical composition, X-ray diffractometry (XRD) for mineral composition, and Fourier transform infrared (FT-IR) spectroscopy & scanning electron microscopy (SEM) for structural changes upon calcination at 500, 700 and, 900 °C were used to assess the suitability of selected lateritic clay sample for geopolymer. The drop in electrical conductivity and greater consumption of calcium hydroxide by CS-900 confirmed its potential reactivity than CS-700, CS-500, and CS-Control. The quality of geopolymer derived from un-calcined and calcined lateritic clay samples by alkali activation was evaluated by comparing results of compressive strength, water absorption test, and stability in the aggressive environment of chloride, FT-IR, XRD, and SEM analyses. The experimental results reveal that the quality of geopolymer enhances as the calcination temperature of the lateritic clay sample increases, However, calcination of the lateritic clay sample at 900 °C gives significant results and yield good quality geopolymer with 24.8 MPa of compressive strength, 7.07% of water absorption and 2.22% loss in mass in an aggressive environment. 相似文献
78.
Let be a polynomial of degree n and for any complex number α, let denote the polar derivative of with respect to α. In this paper, we present an integral inequality for the polar derivative of a polynomial. Our theorem includes as special cases several interesting generalisations and refinements of Erdöx–Lax theorem. 相似文献
79.
Enantioselective Synthesis of Spiroindenes by Enol‐Directed Rhodium(III)‐Catalyzed CH Functionalization and Spiroannulation 下载免费PDF全文
Dr. Suresh Reddy Chidipudi Dr. David J. Burns Imtiaz Khan Prof. Hon Wai Lam 《Angewandte Chemie (International ed. in English)》2015,54(47):13975-13979
Chiral cyclopentadienyl rhodium complexes promote highly enantioselective enol‐directed C(sp2)‐H functionalization and oxidative annulation with alkynes to give spiroindenes containing all‐carbon quaternary stereocenters. High selectivity between two possible directing groups, as well as control of the direction of rotation in the isomerization of an O‐bound rhodium enolate into the C‐bound isomer, appear to be critical for high enantiomeric excesses. 相似文献
80.
Used lubricating oil from vehicles was treated with various types of chemicals to be regenerated. It was found that used lubricating oil could be reclaimed with sulphuric acid, sodium hydroxide, sodium phosphate, ammonium sulphate and rosin. Viscosity and pour point of the reclaimed lubricating oil were improved with the additive methyl methacrylate. The reclaimed lubricating oil was characterized by four‐ball ma chine and it was found that wear scar diameter (WSD) has greatly been de creased with the reclamation. The results of atomic absorption spectrophotometer also show that wear metals have also been de creased to an appreciable amount in there claimed lubricating oil. 相似文献