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111.
Synthesis,Characterization, and Antibacterial Activity of Novel (1H‐Benzo[d]imidazole‐2‐yl)‐6‐(diethylamino)‐3H‐one‐xanthene,Phenoxazine, and Oxazine 下载免费PDF全文
Vikas S. Patil Vikas S. Padalkar Kiran R. Phatangare Prashant G. Umape Bhushan N. Borase N. Sekar 《Journal of heterocyclic chemistry》2015,52(1):124-129
A series of novel (1H‐benzo[d]imidazole‐2‐yl)‐6‐(diethylamino)‐3H‐one‐xanthene, phenoxazine, and oxazine derivatives have been synthesized from 2‐(2′,4′‐dihydroxyphenyl) benzimidazole intermediate. Synthesized compounds 8a , 8b , 8c , 8d are fluorescent in solution, photophysical properties of compounds were studied and results revealed that compounds absorb and emit in UV–visible region with good fluorescence quantum yield. Synthesized compounds are thermally stable up to 300°C. The antibacterial activities of the synthesized compounds were studied by the well‐diffusion method. Escherichia coli (ATTC‐25922), Staphylococcus aureus (ATCC‐25923), Micrococcus (ATCC‐4698), and Bacillus subtilis (ATCC‐55422) were used to investigate the antibacterial activities. 相似文献
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Patil Priyanka T. Warekar Poojali P. Patil Kirti T. Jamale Dattatraya K. Kolekar Govind B. Anbhule Prashant V. 《Research on Chemical Intermediates》2017,43(7):4103-4114
Research on Chemical Intermediates - A convenient and new method has been developed for the synthesis of highly substituted dihydro-2H-dipyrimido[1,2-a,4,5-d]pyrimidine-2,4(3H)-dione derivatives by... 相似文献
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Syntheses of New Unsymmetrical 2,5‐Disubstituted‐1,3,4‐oxadiazoles and 1,2,4‐Triazolo[3,4‐b]‐1,3,4‐thiadiazoles Bearing Thieno[2,3‐c]pyrazolo Moiety 下载免费PDF全文
Shivaraj P. Patil Shrikant B. Kanawade Dinesh C. Bhavsar Prashant S. Nikam Sachin A. Gangurde Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(2):368-373
New series of (thieno[2,3‐c]pyrazolo‐5‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles 10a , 10b , 10c and (thieno[2,3‐c]pyrazol‐5‐yl)‐1,3,4‐oxadiazol‐3(2H)‐yl)ethanones 6a , 6b , 6c has been synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by multistep reaction sequence. (5‐Aryl‐1,3,4‐oxadiazol‐2‐yl)‐1H‐thieno[2,3‐c]pyrazoles 4a , 4b , 4c were also synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by cyclization with various aromatic carboxylic acids. The hydrazide 3 was obtained by reaction of thieno[2,3‐c]pyrazole‐5‐carboxylate 2 with hydrazine hydrate in good yield, and compound 2 was obtained by the reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde 1 and 2‐ethyl thioglycolate in presence of sodium alcoholate in good yield. 相似文献
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A multi-walled carbon nanotube (MWCNT) film-modified glassy carbon electrode (GCE) was constructed for the determination of an antihistamine drug, cetirizine dihydrochloride (CTZH) using cyclic voltammetry (CV). Owing to the unique structure and extraordinary properties of MWCNT, the MWCNT film has shown an obvious electrocatalytic activity towards oxidation of CTZH, since it facilitates the electron transfer and significantly enhances the oxidation peak current of CTZH. All experimental parameters have been optimized. Under the optimum conditions, the oxidation peak current was linearly proportional to the concentration of CTZH in the range from 5.0×10(-7) to 1.0×10(-5)M. The detection limit was 7.07×10(-8)M with 180s accumulation. Finally, the proposed sensitive and simple electrochemical method was successfully applied to CTZH determination in pharmaceutical and urine samples. 相似文献
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D. T. Patil S. L. Bhattar G. B. Kolekar S. R. Patil 《Journal of solution chemistry》2011,40(2):211-223
The molecular interaction between quinine sulfate [QS] and riboflavin [RF] was investigated by fluorescence and UV-VIS absorption spectroscopy in aqueous solutions. The fluorescence of QS was quenched by RF. The Stern-Volmer quenching equation was successfully applied and the corresponding thermodynamic parameters enthalpy change (??H), Gibbs energy change (??G) and entropy change (??S) were calculated at different temperatures (294, 301, 307 and 314 K) according to the van??t Hoff equation. This information showed that hydrogen bonds play a major role in stabilizing the complex. The value of the critical energy transfer distance (R 0) was found to be 46.47 Å, less than 50 Å, which proves that an efficient resonance energy transfer takes place between QS (donor) and RF (acceptor). The oxidation and reduction potentials determined from cyclic voltammetry indicated that association of QS and RF occurs in the excited state by electron transfer. The fluorescence quenching method was successfully applied for the direct determination of riboflavin (vitamin B2) from pharmaceutical samples. 相似文献
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A mild,efficient and high yielding protocol for the synthesis of 2,2'-arylmethelene dicyclohexane-1,3-dione derivatives at room temperature and 9-aryl-l,8-dihydrooctahydroxanthene at conventional heating using cesium fluoride as a catalyst is reported.The major advantages of this reaction are excellent yield,very short reaction time and use of inexpensive catalyst. 相似文献