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排序方式: 共有265条查询结果,搜索用时 250 毫秒
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Krishna Raman Surendra S. Parmar Shiva P. Singh 《Journal of heterocyclic chemistry》1980,17(5):1137-1139
A series of 1-(5-phenyl-2H-tetrazol-2-ylacetyl)-4-substituted thiosemicarbazids were prepared as possible antiinflammatory agents. Their antiproteolytic activity was reported. 相似文献
3.
S. P. Singh S. S. Parmar V. I. Stenberg S. A. Farnum 《Journal of heterocyclic chemistry》1978,15(1):13-16
The 13C nmr chemical shifts of phenylbutazone, oxyphenbutazone, indomethacin and indole-3-acetic acid are reported. The assignments of various carbon resonances are made on the basis of the substitution effects on benzene shifts, multiplicities generated in SFORD spectra, nuclear overhauser enhancement for protonated carbons, and the comparison with analogous compounds. 相似文献
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Sarjit S. Sandhu Miss Sukhvinder Baweja Swarn S. Parmar 《Transition Metal Chemistry》1980,5(1):299-302
Summary Ten complexes of nickel(II) and cobalt(II) witho-phenylenebis(diphenylarsine), (pdpa) ando-phenylenebis(di-p-tolylarsine), (pdta) have been synthesised. The stoichiometry of complexes is markedly dependent upon the reaction temperature, thus reaction atca. 0° gives the M(A-A)2X2 chelates, [M = Ni, X = Br, (A-A) = pdpa; M = Ni, X = I, (A-A) = pdpa, pdta; M = Co, X = CNS, (A-A) = pdpa] whereas at higher temperatures the M(A-A)X2 chelates [M = Ni, X = Br, I, (A-A) = pdpa, pdta; M = Co, X = CNS, (A-A) = pdpa or pdta] are obtained. The Ni(A-A)2I2 compounds can be converted into Ni(A-A)I2 by boiling under reflux in n-BuOH; the conversion can be reversed by cooling a CH2Cl2 solution of the latter at or below 0°. Stereochemical assignments of all the new complexes have been made on the basis of room temperature eff values, molar conductance, i.r. and u.v. data. 相似文献
6.
Bhagwan R. Pandey Sushil Kumar Shiva P. Singh Surendra S. Parmar 《Journal of heterocyclic chemistry》1980,17(5):1119-1120
Several 4-(arylaminothiocarbonyl)-1-(1-o-methoxyphenylcarbamido)-ethylpiperazines were synthesized and evaluated for their anticonvulsant activity against pentylenetetrazol-induced seizures in mice. The ability of substituted piperazines to inhibit in vitro respiratory activity of rat brain homogenates was also determined to study their structure-activity relationship. 相似文献
7.
Paresh J. Kothari Shiva P. Singh Surendra S. Parmar Virgil I. Stenberg 《Journal of heterocyclic chemistry》1980,17(7):1393-1398
Several 1-(5-aryl-2H-tetrazol-2-ylacetyl)-4-substituted thiosemicarbazides and 5-(5-aryl-2H-tetrazol-2-yl-methyl)-4-substituted-s-triazole-3-thiols were synthesized as possible antiinflammatory agents. These compounds were characterized by their elemental, infrared and nuclear magnetic resonance analysis. 相似文献
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Polymeric UV absorbers have been prepared by free-radical solution copolymerization at 75°C of methyl methacrylate and 2-hydroxy-4-methacryloyloxybenzophenone monomers at low conversion (around 10%). The composition of the copolymers was determined by UV, IR, and NMR studies. The molecular weight was estimated by GPC. The reactivity ratios were determined by several methods. Viscosity was used to study the effect of copolymer composition and solvents. The copolymers were also analyzed by TGA and DSC, and DSC was used to study the effect of copolymer composition on Tg. 相似文献
10.
The reaction of ribonucleoside‐5′‐phosphoroimidazolide with a tributylammonium orthophosphate in anhydrous dimethylformamide at room temperature provides a general method for the synthesis of nucleoside‐5′‐diphosphates. The novelty of the approach is to use the triethylammonium salt of 5′‐monophosphate nucleoside derivative prior to the imidazolate reaction with imidazole, triphenylphosphine, and 2,2′‐dithiodipyridine. Deprotection, followed by displacement of the imidazole moiety using tributylammonium orthophosphate and a catalytic amount of zinc chloride in dimethylformamide gave the desired 5′‐diphosphate products. The triethyl ammonium salt of 5′‐diphosphate nucleosides was purified by flash chromatography using DEAE (diethylaminoethyl weak anion exchange resin) Sepharosa fast flow packed in an XK 50/60 column on an Akta FPLC (Fast Protein Liquid Chromatography). Synthesis procedures are reported for adenosine‐5′‐diphosphate, uridine‐5′‐diphosphate, cytidine‐5′‐diphosphate, and guanosine‐5′‐diphosphate. Yields for the displacement reactions ranged from 95 to 97%. Thus, this method offers the advantages of shorter reaction time, greater product yield, and a more cost‐effective synthetic route. 相似文献