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排序方式: 共有407条查询结果,搜索用时 15 毫秒
91.
R. C. Arora V. K. Rastogi A. K. Agrawal S. S. Parmar 《Journal of heterocyclic chemistry》1978,15(5):869-871
Some substituted 2-ethyl-3-(4-hydrazinocarbonylphenyl)-4-quinazolones and 2-ethyl-3-(4-hydrazinocarbonylmethylphenyl)-4-quinazolones were synthesized and characterized by their sharp melting points, elemental analyses and spectral data. 相似文献
92.
This paper describes the preparation of the halogeno complexes, HgX2(o-R2AsC6H4CO2H) (X = Cl, Br, I, and R = Et; X = Br, I, and R-C6H11) and the carboxylate complexes, M(o-R2-AsC6H4CO2)2nL(M = Cd, R = Et, C6H11 and n = O; M = Zn; R = Et; nL = H2O; M = Zn, R = C6H11, nL = 3H2O; M = Hg, R = p-tolyl, nL = 2H2O; M = Hg, R = Me, Ph; C6H11 and nL = EtOH). The structures already reported for the halogeno complexes with R = Ph, Me, p-tolyl and X = Cl, Br, I, have been revised on the basis of detailed scrutiny of the IR spectral data and all these complexes have been divided into four structural types out of which three retain the acid dimer unit of the free ligand. In the carboxylate complexes the lowering of νs, CO2 band and the marginal change in the νas CO2 band with respect to those of the corresponding ligand sodium salts have been attributed to the existence of a novel resonating chelating system with the possibility of having a ring current. 相似文献
93.
94.
Sunil K. Sharma Sumit Kumar Eugene F. Barry Arthur C. Watterson Virinder S. Parmar 《Microchemical Journal》2008,90(2):89-92
The research described here elucidates the fundamental interactions of various cations with phenolic moieties constituting the side chains of novel copolymers. The phenolic group was chosen because similar interactions of the tyrosine (Tyr) moiety in proteins with alkaline earth cations are of particular interest for some biochemical systems where both the alkaline earth cations and the aromatic compounds are abundant. The present study has revealed the preferred binding site for our polymeric systems. 相似文献
95.
96.
S. P. Singh S. Kumar B. R. Pandey S. S. Parmar 《Journal of heterocyclic chemistry》1978,15(1):175-176
Some 10-(substituted phenylhydrazonoacetyl)phenothiazines were synthesized as possible anticonvulsants. These compounds were investigated for their anticonvulsant activity and inhibitory effects on the oxidation of pyruvic acid by rat brain homogenates. 相似文献
97.
Shiva P. Singh Surendra S. Parmar Sylvia A. Farnum Virgil I. Stenberg 《Journal of heterocyclic chemistry》1978,15(7):1083-1087
The natural abundance carbon-13 nuclear magnetic resonance spectra of diazepam, clonazepam, flurazepam and chlordiazepoxide were recorded in suitable solvent using the Fourier transform technique on a JEOL FX-60 spectrometer. The relaxation time (T1) of these compounds were also measured. The chemical shift of the various carbon resonances have been assigned on the basis of chemical shift theory, multiplicity generated in single-frequency off-resonance decoupled spectra, relaxation time and the chemical shifts of the model compounds. 相似文献
98.
S. P. Singh S. S. Parmar V. I. Stenberg S. A. Farnurn 《Journal of heterocyclic chemistry》1978,15(4):541-544
The 13C nmr ehemieal shifts of 1,2,3,4-tetrahydroisoquinoline, salsolidine and laudanosine are reported. The various carbon resonances have been assigned on the basis of chemical shift theory, intensity of the signals, multiplicities generated in SFORD spectra and the comparison with model compounds. 相似文献
99.
Kumar R Bruno F Parmar VS Kumar J Watterson AC Chittibabu KG Samuelson LA 《Chemical communications (Cambridge, England)》2004,(7):862-863
Environmentally benign synthesis of novel pegylated polyphenolics, by combining the extraordinary selectivities of a lipase and an oxidase to develop polymeric electrolytes for applications in dye sensitised solar cells. 相似文献
100.
Amitabh Jha Sanjay Malhotra Virinder S. Parmar William Errington 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):899-900
The title compound, 2,2‐dimethylchroman‐6‐ol, C11H14O2, has been identified as a side product from the condensation of hydroquinone with 2‐methylbut‐3‐en‐2‐ol. The pyran ring has a half‐chair conformation. The hydroxyl groups are involved in intermolecular hydrogen bonding which generates infinite spiral chains around the fourfold screw axes; the O?O hydrogen‐bonded distances are 2.661 (1) Å. 相似文献