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1.
B. Sridhar K. Ravikumar Y. S. Sadanandam 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(12):o687-o690
The title compound, C22H19N3O2S, crystallizes in two polymorphic forms having the same space group, viz. P, with Z′ = 2 and Z′ = 1. In both polymorphs, the planar thiazole ring is fused cis with the dihydropyrimidine ring, the carbamoyl group is in an extended conformation with an anticlinal orientation with respect to the pyrimidine ring, and the phenyl ring is attached to the pyrimidine ring approximately at a right angle. The two polymorphs have different interplanar angles between the phenyl and thiazole rings. The molecules are linked by N—H⋯O and C—H⋯O hydrogen bonds. 相似文献
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Interaction potential models for bulk Zns,Zns nanoparticle,and Zns nanoparticle‐PMMA from first‐principles 下载免费PDF全文
Sadanandam Namsani Nisanth N. Nair Jayant K. Singh 《Journal of computational chemistry》2015,36(15):1176-1186
An ab initio derived transferable polarizable force‐field has been developed for Zinc sulphide (ZnS) nanoparticle (NP) and ZnS NP‐PMMA nanocomposite. The structure and elastic constants of bulk ZnS using the new force‐field are within a few percent of experimental observables. The new force‐field show remarkable ability to reproduce structures and nucleation energies of nanoclusters (Zn1S1‐Zn12S12) as validated with that of the density functional theory calculations. A qualitative agreement of the radial distribution functions of Zn? O, in a ZnS nanocluster‐PMMA system, obtained using molecular mechanics molecular dynamics (MD) and ab initio MD (AIMD) simulations indicates that the ZnS–PMMA interaction through Zn? O bonding is explained satisfactorily by our force‐field. © 2015 Wiley Periodicals, Inc. 相似文献
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M. Bidya Sagar K. Ravikumar S. Mehdi Y.S. Sadanandam K.T. Giju E.D. Jemmis 《Journal of chemical crystallography》1999,29(4):481-491
A series of 4(x-substituted phenyl)-1,4-dihydropyridines (x=2—CF3 (1), 2-CH3 (2), 2-OCH3 (3) and 2,4-Cl (4)) with a new substituent, the N-methylcarbamoyl (CONHCH3) group at C3 and C5 are crystallographically characterized and a comparison has been made with important conformational parameters obtained theoretically. The dihydropyridine rings are in shallow boat conformation. The phenyl substituent orientation is synperiplanar. Both the carbonyl groups are oriented anticlinal in 1, 2 and 3; but in 4, one is synclinal and the other synperiplanar with the adjacent double bond. The presence of solvent molecules in 1 (CH3OH), 2 (CH3OH), and 3 (H2O) has significantly changed the hydrogen bonding pattern. Theoretical studies at the semiempirical AM1 MO level reproduces the general features of the structures. The near planarity of the DHP ring and the orientation of the phenyl substituent make 1 and 2 encouraging targets for pharmacological, study. Crystallographic Data:1: a = 8.793(2), b = 29.962(5), c = 8.215(2) Å, = 115.28(2)°, Monoclinic, P21/c;
2: a = 8.799(2), b = 15.789(3), c = 14.074(2) Å, = 100.25(2)°, Monoclinic, P21/n; 3: a = 8.347(1), b = 8.986(1), c = 13.749(2) Å, = 97.50(1), = 94.78(1), = 101.38(1)° Triclinic, P1¯4: a = 12.928(3), b = 14.506(3), c = 9.740(2) Å, Orthorhombic, Pca21. 相似文献
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G. Y. S. K. Swamy B. Sridhar K. Ravikumar Y. S. Sadanandam 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):o80-o83
The molecules of (±)‐2‐(4‐methoxyphenyl)‐1‐phenethyl‐2,3‐dihydroquinazolin‐4(1H)‐one, C23H22N2O2, (I), and (±)‐2‐(1,3‐benzodioxol‐5‐yl)‐1‐phenethyl‐2,3‐dihydroquinazolin‐4(1H)‐one, C23H20N2O3, (II), have T‐shaped forms in the crystal structure. The tetrahydropyrimidine ring in both structures adopts a sofa conformation. Both molecules are linked by N—H...O and C—H...O hydrogen bonds to form sheets built from alternating R22(8) and R44(26) [R44(24) in (II)] edge‐fused rings. Additionally, the structures are stabilized by extensive C—H...π interactions. 相似文献
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D. Shobha M. Adharvana Chari P. Sadanandam K. Mukkanti 《Journal of heterocyclic chemistry》2008,45(4):1225-1227
DDQ catalyzes efficiently the three‐component condensation reaction of aldehyde, β‐ketoester and urea in refluxing acetonitrile to afford the corresponding dihydropyrimidinones. Compared to the classical Biginelli reaction conditions, this new approach consistently has the advantage of excellent yields (80‐92%) and short reaction times 1.5‐2.5 h. 相似文献
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The temperature variation of the lattice parameter of CsPbCl3 in the cubic phase has been studied by x-ray method, from a determination of the precision lattice parameter at various temperatures,
ranging from 50°C to 400°C. The coefficient of thermal expansion of CsPbCl3 can be expressed by the quadratic equation,α
T
= 21.6 × 10−6 + 2.44 × 10−9
T + 5.90 × 10−11
T
2. 相似文献
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Praveen Kumar Mupparapu Narasimha Swamy Thirukovela Sadanandam Gullapelli Mohan Kurra Srinivas Gali Namratha Vaddiraju 《Journal of heterocyclic chemistry》2021,58(6):1379-1387
In this study, a series of novel geminal bis 1,2,3-triazoles linked to 2H-furo[2,3-d][1,3]thiazine-2,4,5(1H,6H)-trione ( 3a-3m ) were prepared in one pot starting from 5-Acetyl-4-Hydroxy-1,3-thiazine-2,6-dione ( 1 ) to 6,6-diazido-2H-furo[2,3-d][1,3]thiazine-2,4,5(1H,6H)-trione ( 2 ) followed by Cu(I)-catalyzed azide-alkyne cycloaddition. The synthesized compounds were further explored for in vitro cytotoxic activity against PC3, A549, MCF-7, and HeLa cell lines and results revealed that the five compounds 3c , 3d , 3g , 3l , and 3m have displayed comparable in vitro cytotoxic activity with the standard drug Etoposide. 相似文献
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