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1.
Ahmad VU Khan A Farooq U Kousar F Khan SS Nawaz SA Abbasi MA Choudhary MI 《Chemical & pharmaceutical bulletin》2005,53(4):378-381
Three new tricyclic cis-clerodane type diterpenoids trivially named as limbatolide A (1), limbatolide B (2) and limbatolide C (3) have been isolated from the roots of Otostegia limbata along with two known compounds; oleanic acid and beta-sitosterol. The structure elucidation of the new compounds was based primarily on two-dimensional (2D) NMR techniques. Compounds 1-3 displayed inhibitory potential in a concentration-dependent manner against acetylcholinesterase (AChE; EC 3.1.1.7) and butyrylcholinesterase (BChE; EC 3.1.1.8) enzymes, respectively. 相似文献
2.
Ahmad VU Zubair M Athar Abbasi M Abid Rashid M Rasool N Nahar Khan S Iqbal Choudhary M Kousar F 《Magnetic resonance in chemistry : MRC》2005,43(6):486-488
The investigation of the chemical constituents of Symplocos racemosa Roxb led to the isolation of two new glycosides, symcomoside A (1) and symcomoside B (2), together with one known glycoside, tortoside C (3), which is reported for the first time from this plant. The structures of the new compounds were determined by 1D and 2D homonuclear and heteronuclear NMR spectroscopy, from chemical evidence and by comparison with published data for closely related compounds. Symcomoside B (2) showed potent inhibitory activity against alpha-glucosidase in a concentration-dependent fashion with an IC50 value of 0.733 +/- 0.033 mM whereas symcomoside A (1) showed very weak inhibitory activity against alpha-glucosidase (9.90% in 0.70 mM). 相似文献
3.
Guido D. Frey Rian D. Dewhurst Shazia Kousar Bruno Donnadieu Guy Bertrand 《Journal of organometallic chemistry》2008,693(8-9):1674-1682
A series of mono- and dicarbene gold(I) complexes of types Au(CAAC)(Cl) [CAAC = cyclic (alkyl)(amino)carbene] (1) and [Au(CAAC)2]+[X]? (X = Cl, AuCl2) (2) have been prepared through reaction of AuCl(SMe2) with free carbenes a–e, and structurally characterized by single X-ray diffraction studies (1a, 1b, 2d, 2e). In addition two new free cyclic (alkyl)(amino)carbenes (c and e) have been synthesized. 相似文献
4.
Farooq U Khan A Ahmad VU Khan SS Kousar F Arshad S 《Chemical & pharmaceutical bulletin》2007,55(3):471-473
Two new tetracyclic diterpenoids trivially named as limbatenolide D (1) and limbatenolide E (2) have been isolated from Otostegia limbata. The structure elucidation of the compounds was based primarily on two-dimensional (2D) NMR techniques and on comparison with the literature data. 相似文献
5.
Shahbaz Ali Muneeba Kousar Qin Xin Dragan Pamu
ar Muhammad Shazib Hameed Rabia Fayyaz 《Entropy (Basel, Switzerland)》2021,23(11)
In this research article, we motivate and introduce the concept of possibility belief interval-valued N-soft sets. It has a great significance for enhancing the performance of decision-making procedures in many theories of uncertainty. The N-soft set theory is arising as an effective mathematical tool for dealing with precision and uncertainties more than the soft set theory. In this regard, we extend the concept of belief interval-valued soft set to possibility belief interval-valued N-soft set (by accumulating possibility and belief interval with N-soft set), and we also explain its practical calculations. To this objective, we defined related theoretical notions, for example, belief interval-valued N-soft set, possibility belief interval-valued N-soft set, their algebraic operations, and examined some of their fundamental properties. Furthermore, we developed two algorithms by using max-AND and min-OR operations of possibility belief interval-valued N-soft set for decision-making problems and also justify its applicability with numerical examples. 相似文献
6.
Ahmad VU Zubair M Abbasi MA Kousar F Rashid MA Rasool N Tareen RB 《Natural product research》2006,20(1):69-74
Phytochemical investigation of Platytaenia multicaule resulted in the isolation of two new ceramides, N-triacontylpentadecanamide and 1,3,4-trihydroxy-2,dodecanoylamino-(24E)-unacotenene, along with two known compounds, beta-sitosterol and beta-sitosterol glycoside. The structure elucidation of the isolated compounds was based primarily on 1D and 2D NMR analyses, including COSY, NOESY, HMQC, and HMBC correlations. 相似文献
7.
Khalil Ur Rehman Muhammad Awais Arif Hussain Nabeela Kousar Muhammad Yousaf Malik 《Mathematical Methods in the Applied Sciences》2019,42(1):24-38
A speculative investigation has been presented to explore the salient features of magnetohydrodynamic (MHD) Prandtl‐Eyring nanofluid over stretching surface. Effects of Navier slip and convective boundary conditions are included in flow configuration. The effects of higher order chemical reactions along with Nield conditions are assumed in the concentration of nanoparticles. The mathematical modelling of the said flow problem accomplished the nonlinear partial differential equations along with appropriate boundary conditions. The nondimensional form of governing problem is yielded with the aid of similarity variables. The pivotal physical quantities, ie, velocity, temperature, and concentration (in nondimensional form), within boundary layer region are computed with shooting technique. The physical significance of flow controlling parameters on velocity, temperature, and concentration is illustrated through graphs. Additionally, thermophysical aspects of fluid near stretching surface (wall friction factor, wall heat flux, and wall mass flux) are instantiated graphically. A comparison of the current solution with reported data is established to validate the accuracy of adapted procedure. It is observed that the current findings agree with existing data. This led to confidence on adapted numerical procedure. 相似文献
8.
Amber Khuram Pervez Akram Waseem Bashir Muhammad Anser Khan Muhammad Sajid Kousar Anila 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2355-2366
Journal of Thermal Analysis and Calorimetry - At higher ambient temperatures during summer months, the cell temperature of a photovoltaic (PV) module increases to 50–60 °C and sometimes... 相似文献
9.
We study the effects of the tidal charge on the equatorial circular motion of neutral test particles near a tidal charged black hole. This analysis investigates stable as well as unstable circular orbits in all possible configurations of nonextremal and extremal cases. It is found that a negative tidal charge will increase the energy and angular momentum of a neutral test particle moving around a black hole. We obtain a continuous region of stability for both extremal and nonextremal cases. We conclude that the region of stability as well as radius of last stable circular orbit shows increasing behavior for Q < 0. 相似文献
10.
KOUSAR Nabeela 《中国科学:物理学 力学 天文学(英文版)》2010,(2)
The non-similarity solution for natural convection from a permeable isothermal vertical wall is considered. The governing boundary-layer equations for non-similarity flow and temperature fields are solved using the homotopy analysis method. The homotopy-Pade' technique is applied to accelerate the convergence of the homotopy-series solution. The influence of physical parameters on the non-similarity flows is investigated in detail. Different from the previous analytic results,the homotopy-series solutions a... 相似文献