• Journal of Electrochemical Science and Technology
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• 제4권2호
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• pp.61-70
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• 2013

Corrosion inhibition of carbon steel in 2M HCl by some benzohydrazide derivatives (I-III) was studied using weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques at $30^{\circ}C$. Polarization studies showed that all the investigated compounds are of mixed type inhibitors. Temperature studies revealed a decrease in efficiency with rise in temperature and corrosion activation energies increased in the presence of the hydrazide derivatives, probably implying that physical adsorption of cationic species may be responsible for the observed inhibition behavior. Electrochemical impedance studies showed that the presence of benzohydrazide derivatives decreases the double layer capacitance and increases the charge transfer resistance. The adsorption of these compounds on carbon steel surface was found to obey Temkin's adsorption isotherm. Synergistic effects increased the inhibition efficiency in the presence of halide additives namely KI and KBr. An inhibition mechanism was proposed in terms of strongly adsorption of inhibitor molecules on carbon steel surface.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3361-3367
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• 2012

Two novel Eu(III) complexes with notable properties have been successfully prepared with hydrazone Schiff base ligands, (E)-2-hydroxy-N'-[(2-hydroxynaphthalen-1-yl)methylene]benzohydrazide (3a) and (E)-4-hydroxy-N'-[(2-hydroxynaphthalen-1-yl)methylene]benzohydrazide (3b). DFT, FMO energy and Mulliken charge distribution studies of the ligands allowed us to hypothesize that their HC=N, > C=O and -OH (naphthyl) groups were involved in coordinating with the $Eu^{3+}$ ion. The eight coordination sites of the $Eu^{3+}$ ion were occupied by the three functional groups of the two ligands (3a or 3b) mentioned above and two water molecules. Similar UV, IR and fluorescence spectra indicated the presence of comparable coordination environments for the $Eu^{3+}$ ion in both complexes. Both the ligands and their complexes exhibited moderate DPPH radical scavenging activity. Moreover, it was found that the Eu(III) complexes exhibited fluorescence properties.

• Natural Product Sciences
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• 제23권1호
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• pp.69-74
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• 2017

A new phenol and hydrazide derivatives were obtained for the first time from the C. giganteawhite by silica gel column chromatography. The structure of the isolated compounds was identified by UV, IR NMR and MS. C. gigantea was scientifically reported for several medicinal properties viz. analgesic, antimicrobial and cytotoxic. In this screening work, anti-microbial activity of test compounds was found to be active against all organisms. Additionally, anti-inflammatory activity of the test groups has reduced the thickness of edema of the hind paw compared to the control group.

• 대한화학회지
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• 제56권2호
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• pp.236-245
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• 2012

The main mycobacterial infection in human is tuberculosis caused by Mycobacterium tuberculosis. Tuberculosis is the leading infectious cause of death in the world. Therefore there is continuing and compelling need for new and improved treatment for tuberculosis. The entire logic towards design of new compounds containing 4-hydroxy-N'-(1,3-thiazoldin- 2-yldene)benzohydrazide moiety is basically for superior antimycobacterial activity. The recent advances in QSAR and computer science have provided a systematic approach to design a structure of any compound and further, the biological activity of the compound can be predicted before synthesis. The 3D-QSAR studies for the set of 4-hydroxy-N'-(1,3-thiazoldin- 2-yldene)benzohydrazide and their derivatives were carried out by using V-life MDS (3.50). The various statistical methods such as Multiple Linear Regression (MLR), Partial Least Square Regression (PLSR), Principle Component Regression(PCR) and K nearest neighbour (kNN) were used. The kNN showed good results having cross validated $r^2$ 0.9319, $r^2$ for external test set 0.8561 and standard error of estimate 0.2195. The docking studies were carried out by using Schrodinger GLIDE module which resulted in good docking score in comparison with the standard isoniazid. The designed compounds were further subjected for synthesis and biological evaluation. Antitubercular evaluation of these compounds showed that (4.a), (4.d) and (4.g) found as potent inhibitor of H37RV.

• 대한화학회지
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• 제54권1호
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• pp.77-87
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• 2010

40여년전에 보고된 이래 병원에서 유래한 메치실린-저항 Staphylococcus aureus (MRSA) 은 세계적으로 큰 문제가 되어왔다. 항균성의 가능성을 가지는 새로운 약품을 개발하기 위하여 N'-[(-3-substituted-4-oxo-1,3-thiazolidin-2-ylidene]-4-hydroxy benzohydrazide (4a-4.i)와 N'-[-(3,4-disubstituted)-1,3-thiazolidin-2ylidene)]-4-hydroxybenzohydrazide (5.a-5.i)~(10.a-10.i)을 적절한 합성방법을 사용하여 합성하였다. 이들 합성된 화합물들은 s. aureus 균주에 대해 생체외 조건에서 분석하였다. 시료 화합물과 표준 화합물에 대해 최소억제농도(MIC)를 결정하였다. 시험한 모든 화합물들은 2000 ${\mu}g$/mL 투여량까지는 독성이 없었고, 사용한 균주에 대해 상당한 항균성을 보였다. 특히 6.f, 7.g, 9.f 와 10.f, 10 i 들이 가장 항균성이 컸다. 이것으로 미루어 파라-히드록시벤조히드라자이드 고리와 치환된 싸이아졸린 고리는 항균성에 필수적임을 알 수 있었다. 3D-QSAR 분석결과로 파라-히드록시벤조히드라자이드의 활성자리에 대한 결합방식을 알게되었다.