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31.
Two simple and sensitive spectrophotometric methods for the determination of cefetamet in either pure form or in its pharmaceutical formulations were described. The method Ⅰ is based on the interaction of 3-methylbenzo[d]- thiazolin-2-one hydrazone (MBTH) with cefetamet in the presence of freshly prepared ferric chloride in a neutral medium. The resulting blue colored product has λmax at 628 nm. The method Ⅱ describes the reduction of ferric ion by the drug to ferrous ion followed by a complex formation reaction with 1,10-phenanthroline (1,10-phen) to form an orange red colored chromogen exhibiting 2max at 510 nm. The products are stable for more than 5 and 8 h respectively. Common excipients used as additives in pharmaceutical preparations do not interfere in the proposed methods. Both methods are highly reproducible and have been applied to a wide variety of pharmaceutical preparations and the results are comparable with those of official methods.  相似文献   
32.
A new 1,2‐dihydroquinazolinone, 2‐(2‐hydroxy‐phenyl)‐3‐[1‐(2‐oxo‐2H‐chromen‐3‐yl)‐ethylideneamino]‐2,3‐dihydro‐1H‐quinazolin‐4‐one (L) and its Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes have been prepared. These were characterized by elemental, spectral [UV–visible, IR, NMR (1H, 13C and 2D heteronuclear correlation) and mass], conductance, magnetic susceptibility and thermal studies. The physicochemical data indicate that the ligand behaves as tridentate with ONO donor sequence towards the metal ions, and trigonal bipyramidal geometry was assigned for complexes. The ligand and its metal complexes were evaluated for their in vivo anti‐inflammatory and analgesic activity. The tested compounds have shown excellent activity, which are almost equipotent to the standard used in the study. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
33.
In this paper, we report our measurements of back-angle oxygen and carbon particle yields from 16O+89Y, 12C+93Nb reactions forming the same compound nucleus 105Ag at the same excitation energy and spin distribution. We find anomalously large oxygen yield and entrance channel dependence at high excitation energies from 16O+89Y reaction implying formation of a dinuclear orbiting complex. Possible connection between nuclear orbiting and fast fission is also discussed.  相似文献   
34.
Copper(II) complexes with 2,2-dihydroxychalkones have been prepared in aqueous alcohol medium and characterised by the elemental analysis. They have 11 stoichiometry and i.r spectra show the involvement of the OH and C=O groups in the bond formation. These copper(II) complexes show magnetic moments in the range of 1.53–1.98 B and are insoluble in common organic solvents. In view of the magnetic data, solubility and electronic spectral evidences, an extended polymeric structure has been proposed for these complexes.  相似文献   
35.
The behavior of 3-chlorobenzothiophene-2-carbonylisothiocyanate 2 towards nitrogen nucleophiles such as primary amines, substituted hydrazines, aryl hydrazines, glycine, anthranilic acid; sulfur nucleophiles such as thioglycolic acid; and oxygen nucleophiles such as substituted phenols has been investigated and found that it proceeds via isothiocyanate heterocyclization to furnish noncondensed heterocyclic compounds containing thiourea, triazole, oxazole, thiazole, and benzoxazole nuclei besides the benzo[b]thiophene nucleus. The structures of the newly synthesized compounds were elucidated on the basis of IR, 1H NMR, and mass spectral data of the compounds, and they have been screened for antimicrobial, analgesic, and anti-inflammatory activities.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   
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