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Amir Azam - One of the best experts on this subject based on the ideXlab platform.
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synthesis Antiamoebic and molecular docking studies of furan thiazolidinone hybrids
European Journal of Medicinal Chemistry, 2016Co-Authors: Mohammad Fawad Ansari, Shadab Miyan Siddiqui, Kamal Ahmad, Fernando Avecilla, Sudhaker Dharavath, S Gourinath, Amir AzamAbstract:Abstract In continuation of our previous work, a series of furan-thiazolidinone hybrids was prepared by Knoevenagel condensation of 3-(furan-2-ylmethyl)-2-(phenylimino)-1, 3-thiazolidin-4-one with different aryl aldehydes in presence of strong base. Some members of the series exhibited remarkable Antiamoebic activity and cell viability. Three compounds (3, 6 and 11) showed excellent binding energy for Entamoeba histolytica O-acetyle- l -serine sulfohydrolase and Entamoeba histolytica thioredoxin reductase. These compounds demonstrated significant inhibition of O-acetyle- l -serine sulfohydrolase. The promising Antiamoebic activity and enzymatic assay of 3, 6 and 11 make them promising molecules for further lead optimization in the development of novel Antiamoebic agents.
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recent progress on the discovery of Antiamoebic agents
ChemInform, 2016Co-Authors: Faisal Hayat, Amir Azam, Dongyun ShinAbstract:A large number of protozoans infect humans but Entamoeba histolytica is the only organism responsible for causing amoebiasis, a deadly disease after malaria. Numerous heterocycle-based Antiamoebic agents have been previously synthesized as E. histolytica inhibitors and while some of these agents have shown moderate activity, the search for a novel and ideal Antiamoebic compound is still ongoing. In this digest Letter, we present the latest data on Antiamoebic agents from 2011 to 2016 based on the different classes of heterocyclic agents.
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design synthesis and biological evaluation of quinazolin 4 3h one schiff base conjugates as potential Antiamoebic agents
Journal of Saudi Chemical Society, 2016Co-Authors: Saba Tariq, Fernando Avecilla, Neelima Mondal, Guru Prasad Sharma, Amir AzamAbstract:Abstract In an effort to develop novel Antiamoebic scaffolds having better efficacy than the standard drug metronidazole (IC 50 = 1.80 μM) used against Entamoeba histolytica , quinazolin-4(3 H )-one Schiff base conjugates were synthesized and evaluated against HM1: IMSS strain of E. histolytica . Out of the thirteen compounds ( S2 - S14 ), six compounds ( S2 , S3 , S4 , S5 , S6 and S11 ) were found to be better inhibitors than metronidazole and showed low cytotoxicity on HeLa cells, a cervical cancer cell line. The structure of intermediate compound S1 was confirmed by crystal structure studies.
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new transition metal complexes containing imidazole rings endowed with potential Antiamoebic activity
MedChemComm, 2016Co-Authors: Amir Azam, Abdul Roouf Bhat, Fareeda Athar, Mohmmad Younus Wani, Abilio J F N SobralAbstract:A useful concept for the rational design of anti-protozoal drug candidates is the complexation of bioactive ligands with transition metals. We previously reported that nitroimidazole acylhydrazones possess excellent Antiamoebic activity; in this study, we synthesized some CuII, CoII and NiII metal complexes and chose 2-(5-methyl-2-nitro-1H-imidazol-1-yl)-N′-[(E)-pyridin-2-ylmethylidene]acetohydrazide as a ligand. Physical and spectroscopic characterization revealed a distorted octahedral geometry for the complexes. The pharmacological characterization, including assays against Entamoeba histolytica and cytotoxicity to mammalian cells, revealed that chelation improves the Antiamoebic activity of the ligand. Docking of the ligand with thioredoxin reductase (EhTrR), a promising target for the treatment of amoebiasis, showed that the inhibitor snugly fits the active site of the target enzyme, which may well explain the excellent inhibitory activity.
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novel ferrocenyl linked pyrazoline analogs as potent Antiamoebic agents
Journal of Heterocyclic Chemistry, 2016Co-Authors: Humaira Parveen, Sayeed Mukhtar, Amir AzamAbstract:Some novel ferrocenyl linked pyrazoline analogs were synthesized, well characterized, and evaluated for in vitro Antiamoebic activity against HM1 : IMSS strain of Entamoeba histolytica. Most of the compounds exhibited higher Antiamoebic activity with the IC50 value in the range of 0.12–1.20 μM, than the reference drug metronidazole, (IC50 value of 1.78 μM). Compound 9 showed the most promising Antiamoebic activity (IC50 = 0.12 μM), concluding that these compounds hold immense potential to be employed as new Antiamoebic agents. Also, being novel, they can be a solution to the increasing resistance that has posed a major problem globally.
Faisal Hayat - One of the best experts on this subject based on the ideXlab platform.
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recent progress on the discovery of Antiamoebic agents
ChemInform, 2016Co-Authors: Faisal Hayat, Amir Azam, Dongyun ShinAbstract:A large number of protozoans infect humans but Entamoeba histolytica is the only organism responsible for causing amoebiasis, a deadly disease after malaria. Numerous heterocycle-based Antiamoebic agents have been previously synthesized as E. histolytica inhibitors and while some of these agents have shown moderate activity, the search for a novel and ideal Antiamoebic compound is still ongoing. In this digest Letter, we present the latest data on Antiamoebic agents from 2011 to 2016 based on the different classes of heterocyclic agents.
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Novel aryl carbamate derivatives of metronidazole as potential Antiamoebic agents
Archives of Pharmacal Research, 2016Co-Authors: Faisal Hayat, Amir Azam, Saba Tariq, Hussain Mustatab Wahedi, Seonghyeok Park, Dongyun ShinAbstract:A series of novel aryl carbamate derivatives of metronidazole (MNZ) were designed, synthesized, and screened for Antiamoebic activity. As compared to MNZ, most of the derivatives exhibited moderate to excellent activity against the HM1:IMSS strain of Entamoeba histolytica. Compounds 7 , 14 , 16 , 19 , and 21 exhibited the most promising Antiamoebic activity with IC_50 values of 0.24, 0.08, 0.26, 0.26, and 0.15 μM, respectively, compared to that of MNZ (1.78 μM). Moreover, from the toxicological studies of these compounds on human melanocytes, the melan-a cell line revealed that the potent compounds are nontoxic at concentrations ranging from 2.5 to 50 μM.
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antiprotozoal activity of chloroquinoline based chalcones
ChemInform, 2011Co-Authors: Faisal Hayat, Emma Moseley, Attar Salahuddin, Robyn L Van Zyl, Amir AzamAbstract:Synthesis and in vitro evaluation for Antiamoebic and antimalarial activities are reported.
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synthesis characterization Antiamoebic activity and cytotoxicity of new pyrazolo 3 4 d pyrimidine 6 one derivatives
Journal of Enzyme Inhibition and Medicinal Chemistry, 2011Co-Authors: Faisal Hayat, Attar Salahuddin, Amir AzamAbstract:A new series of pyrazolo[3,4-d]pyrimidine-6-one derivatives (2a-2j) were prepared by using the Biginelli multicomponent cyclocondensation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (1a), different aromatic aldehydes, and urea with a catalytic amount of HCl at reflux temperature. These compounds were characterized by IR, (1)H NMR, (13)C NMR, and Mass spectral data. In vitro Antiamoebic activity was performed against HM1:IMSS strain of Entamoeba histolytica. The results showed that the compounds 2b, 2i, and 2j with IC(50) values of 0.37 µM, 0.04 µM, and 0.06 µM, respectively, exhibited better Antiamoebic activity than the standard drug metronidazole (IC(50) = 1.33 µM). The toxicological studies of these compounds on human breast cancer MCF-7 cell line showed that the compounds 2b, 2i, and 2j exhibited >80% viability at the concentration range of 1.56-50 µM.
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synthesis characterization Antiamoebic activity and cytotoxicity of novel 2 quinolin 8 yloxy acetohydrazones and their cyclized products 1 2 3 thiadiazole and 1 2 3 selenadiazole derivatives
ChemInform, 2011Co-Authors: Faisal Hayat, Attar Salahuddin, Jamil Zargan, Amir AzamAbstract:All intermediates (III) and products (IV) and (V) are assayed for their Antiamoebic activity using HM1:IMSS strain of E.
Fareeda Athar - One of the best experts on this subject based on the ideXlab platform.
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new transition metal complexes containing imidazole rings endowed with potential Antiamoebic activity
MedChemComm, 2016Co-Authors: Amir Azam, Abdul Roouf Bhat, Fareeda Athar, Mohmmad Younus Wani, Abilio J F N SobralAbstract:A useful concept for the rational design of anti-protozoal drug candidates is the complexation of bioactive ligands with transition metals. We previously reported that nitroimidazole acylhydrazones possess excellent Antiamoebic activity; in this study, we synthesized some CuII, CoII and NiII metal complexes and chose 2-(5-methyl-2-nitro-1H-imidazol-1-yl)-N′-[(E)-pyridin-2-ylmethylidene]acetohydrazide as a ligand. Physical and spectroscopic characterization revealed a distorted octahedral geometry for the complexes. The pharmacological characterization, including assays against Entamoeba histolytica and cytotoxicity to mammalian cells, revealed that chelation improves the Antiamoebic activity of the ligand. Docking of the ligand with thioredoxin reductase (EhTrR), a promising target for the treatment of amoebiasis, showed that the inhibitor snugly fits the active site of the target enzyme, which may well explain the excellent inhibitory activity.
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probing the Antiamoebic and cytotoxicity potency of novel tetrazole and triazine derivatives
European Journal of Medicinal Chemistry, 2012Co-Authors: Mohmmad Younus Wani, Amir Azam, Abdul Roouf Bhat, Inho Choi, Fareeda AtharAbstract:Abstract A series of compounds bearing a Tetrazole and Triazine ring motif conjugated with a SO 2 NH function were synthesized and investigated for their Antiamoebic potency. Cytotoxicity of the compounds was checked on human hepatocellular carcinoma cell line HepG2. Incorporation of Triazine ring in place of tetrazole resulted in a precipitous increase in the Antiamoebic activity of the compounds. Antiamoebic activity of the investigated compounds was found to be position and substituent dependent. In vitro cytotoxicity results revealed noncytotoxic nature of all the tested compounds up to a concentration of 25 μM. Compound 5c and 5d were obtained as least cytotoxic (IC 50 > 100 μM) and excellent Entamoeba histolytica inhibitors with IC 50 values of 1.05 μM and 1.02 μM respectively.
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structure activity relationships of mononuclear metal thiosemicarbazone complexes endowed with potent antiplasmodial and Antiamoebic activities
Bioorganic & Medicinal Chemistry, 2010Co-Authors: Deepa Bahl, Fareeda Athar, Milena Botelho Pereira Soares, Diogo Rodrigo Magalhaes Moreira, Rajendra M Srivastava, Ana Cristina Lima Leite, Amir AzamAbstract:A useful concept for the rational design of antiparasitic drug candidates is the complexation of bioactive ligands with transition metals. In view of this, an investigation was conducted into a new set of metal complexes as potential antiplasmodium and Antiamoebic agents, in order to examine the importance of metallic atoms, as well as the kind of sphere of co-ordination, in these biological properties. Four functionalized furyl-thiosemicarbazones (NT1–4) treated with divalent metals (Cu, Co, Pt, and Pd) to form the mononuclear metallic complexes of formula [M(L)2Cl2] or [M(L)Cl2] were examined. The pharmacological characterization, including assays against Plasmodium falciparum and Entamoeba histolytica, cytotoxicity to mammalian cells, and interaction with pBR 322 plasmid DNA was performed. Structure–activity relationship data revealed that the metallic complexation plays an essential role in antiprotozoal activity, rather than the simple presence of the ligand or metal alone. Important steps towards identification of novel antiplasmodium (NT1Cu, IC50 of 4.6 lM) and Antiamoebic (NT2Pd, IC50 of 0.6 lM) drug prototypes were achieved. Of particular relevance to this work, these prototypes were able to reduce the proliferation of these parasites at concentrations that are not cytotoxic to mammalian cells.
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synthesis spectral studies and Antiamoebic activity of new 1 n substituted thiocarbamoyl 3 phenyl 2 pyrazolines
ChemInform, 2009Co-Authors: Mohammad Abid, Fareeda Athar, Abdul Roouf Bhat, Amir AzamAbstract:Abstract Thirty new pyrazoline derivatives were synthesized by cyclization of Mannich bases with thiosemicarbazides being substituted by different cyclic and aromatic amines. The structures of the compounds were elucidated by elemental analyses, UV, IR, 1 H and 13 C NMR and ESI-MS spectral data. The in vitro Antiamoebic activity was evaluated against Entamoeba histolytica in comparison with metronidazole used as reference substance. Out of the 30 compounds screened for Antiamoebic activity, 10 ( 5 , 6 , 15 , 18 , 25 – 30 ) were found to be better inhibitors of E. histolytica since they showed lesser IC 50 values than metronidazole. The preliminary results indicated that the presence of 3-chloro or 3-bromo substituent on the phenyl ring at position 3 of the pyrazoline ring enhanced the Antiamoebic activity as compared to unsubstituted phenyl ring. The study suggests that the preliminary activity of these compounds may further be explored for the development of new targets for amoebiasis.
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cyclooctadiene ru ii complexes of thiophene 2 carboxaldehyde derived thiosemicarbazones synthesis characterization and Antiamoebic activity
European Journal of Medicinal Chemistry, 2006Co-Authors: Shailendra Kumar Singh, Fareeda Athar, Mannar R Maurya, Amir AzamAbstract:Thiosemicarbazones (TSC) 1-10 were synthesized by condensing substituted thiosemicarbazide with thiophene-2-carboxaldehyde. These thiosemicarbazones were further reacted with [Ru(eta4-C8H12)(CH3CN)2Cl2] to form complexes of the type [Ru(eta4-C8H12)(TSC)Cl2] 1a-10a. Thiosemicarbazones exhibited Antiamoebic activity in the range IC50=1.09-5.42 microM. In vitro assessment of Antiamoebic activity indicated that the thiosemicarbazones 3, IC50=1.67 microM, 4, IC50=1.11 microM and 6, IC50=1.09 microM showed substantially less IC50 value than metronidazole (IC50=1.87 microM), a commonly used drug against amoebiasis. Cyclooctadiene Ru(II) complexes of thiosemicarbazones showed significant improvement in Antiamoebic activity (IC50=0.30-1.39 microM). All the complexes possess noteworthy potencies and showed less IC50 values than metronidazole against HK-9 strain of Entamoeba histolytica. Among all the complexes, the most promising Antiamoebic activities was shown by the complexes 4a and 6a (IC50=0.31 microM of 4a and IC50=0.30 microM of 6a versus metronidazole).
Attar Salahuddin - One of the best experts on this subject based on the ideXlab platform.
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pyrazolo 3 4 d pyrimidine analogues synthesis characterization and their in vitro Antiamoebic activity
Medicinal Chemistry Research, 2013Co-Authors: Shadab Miyan Siddiqui, Attar Salahuddin, Amir AzamAbstract:Pyrazolo[3,4-d]pyrimidine analogues were synthesized by treating 3-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4-amine with different sulfonyl chlorides and triethylamine in dry dichloromethane. The structure of all the compounds was elucidated by spectral data and their purity was confirmed by elemental analysis. In vitro Antiamoebic activity was performed against HM1:IMSS strain of Entamoeba histolytica and two compounds, 4 (IC50 = 0.57) and 6 (IC50 = 0.68), were found better inhibitors than the reference drug metronidazole (IC50 = 1.80). Further, both the compounds (4 and 6) were low cytotoxic against the human breast cancer MCF-7 cell line in the concentration range of 2.5–250 μM. These preliminary results reveal that pyrazolo[3,4-d]pyrimidine analogues could help in designing better molecules with enhanced Antiamoebic activity.
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synthesis characterization and Antiamoebic activity of some hydrazone and azole derivatives bearing pyridyl moiety as a promising heterocyclic scaffold
European Journal of Medicinal Chemistry, 2012Co-Authors: Shadab Miyan Siddiqui, Attar Salahuddin, Amir AzamAbstract:Abstract In an effort to develop effective Antiamoebic agents, some hydrazones and azoles containing pyridyl moiety were synthesized and screened for in vitro Antiamoebic activity against HM1:IMSS strain of Entamoeba histolytica . Among all the compounds, only five compounds ( 1 , 3 , 5 , 9 and 11 ) were found to be better inhibitors of growth of E. histolytica than the reference drug metronidazole. The cytotoxic studies of these compounds on human breast cancer MCF-7 cell line revealed that all the compounds were low-cytotoxic in the concentration range of 2.5–250 μM.
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antiprotozoal activity of chloroquinoline based chalcones
ChemInform, 2011Co-Authors: Faisal Hayat, Emma Moseley, Attar Salahuddin, Robyn L Van Zyl, Amir AzamAbstract:Synthesis and in vitro evaluation for Antiamoebic and antimalarial activities are reported.
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synthesis characterization Antiamoebic activity and cytotoxicity of new pyrazolo 3 4 d pyrimidine 6 one derivatives
Journal of Enzyme Inhibition and Medicinal Chemistry, 2011Co-Authors: Faisal Hayat, Attar Salahuddin, Amir AzamAbstract:A new series of pyrazolo[3,4-d]pyrimidine-6-one derivatives (2a-2j) were prepared by using the Biginelli multicomponent cyclocondensation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (1a), different aromatic aldehydes, and urea with a catalytic amount of HCl at reflux temperature. These compounds were characterized by IR, (1)H NMR, (13)C NMR, and Mass spectral data. In vitro Antiamoebic activity was performed against HM1:IMSS strain of Entamoeba histolytica. The results showed that the compounds 2b, 2i, and 2j with IC(50) values of 0.37 µM, 0.04 µM, and 0.06 µM, respectively, exhibited better Antiamoebic activity than the standard drug metronidazole (IC(50) = 1.33 µM). The toxicological studies of these compounds on human breast cancer MCF-7 cell line showed that the compounds 2b, 2i, and 2j exhibited >80% viability at the concentration range of 1.56-50 µM.
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synthesis characterization Antiamoebic activity and cytotoxicity of novel 2 quinolin 8 yloxy acetohydrazones and their cyclized products 1 2 3 thiadiazole and 1 2 3 selenadiazole derivatives
ChemInform, 2011Co-Authors: Faisal Hayat, Attar Salahuddin, Jamil Zargan, Amir AzamAbstract:All intermediates (III) and products (IV) and (V) are assayed for their Antiamoebic activity using HM1:IMSS strain of E.
Shailendra Kumar Singh - One of the best experts on this subject based on the ideXlab platform.
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activity of extracts and procesterol from calotropis gigantea against entamoeba histolytica
Natural Product Communications, 2010Co-Authors: Shailendra Kumar Singh, Neelam Bharti, Manoj Chugh, Fehmida Naqvi, Amir AzamAbstract:Extracts from the root bark of Calotropis gigantea were subjected to bioactivity-guided fractionation using growth inhibitory effects against Entamoeba histolytica. The n-hexane soluble portion of the chloroform extract showed in vitro Antiamoebic activity against the HK-9 strain of Entamoeba histolytica. Chromatographic separation of the chloroform extract afforded the known compound, procesterol, which showed activity against E. histolytica.
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cyclooctadiene ru ii complexes of thiophene 2 carboxaldehyde derived thiosemicarbazones synthesis characterization and Antiamoebic activity
European Journal of Medicinal Chemistry, 2006Co-Authors: Shailendra Kumar Singh, Fareeda Athar, Mannar R Maurya, Amir AzamAbstract:Thiosemicarbazones (TSC) 1-10 were synthesized by condensing substituted thiosemicarbazide with thiophene-2-carboxaldehyde. These thiosemicarbazones were further reacted with [Ru(eta4-C8H12)(CH3CN)2Cl2] to form complexes of the type [Ru(eta4-C8H12)(TSC)Cl2] 1a-10a. Thiosemicarbazones exhibited Antiamoebic activity in the range IC50=1.09-5.42 microM. In vitro assessment of Antiamoebic activity indicated that the thiosemicarbazones 3, IC50=1.67 microM, 4, IC50=1.11 microM and 6, IC50=1.09 microM showed substantially less IC50 value than metronidazole (IC50=1.87 microM), a commonly used drug against amoebiasis. Cyclooctadiene Ru(II) complexes of thiosemicarbazones showed significant improvement in Antiamoebic activity (IC50=0.30-1.39 microM). All the complexes possess noteworthy potencies and showed less IC50 values than metronidazole against HK-9 strain of Entamoeba histolytica. Among all the complexes, the most promising Antiamoebic activities was shown by the complexes 4a and 6a (IC50=0.31 microM of 4a and IC50=0.30 microM of 6a versus metronidazole).
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synthesis spectral studies and in vitro assessment for Antiamoebic activity of new cyclooctadiene ruthenium ii complexes with 5 nitrothiophene 2 carboxaldehyde thiosemicarbazones
Bioorganic & Medicinal Chemistry Letters, 2005Co-Authors: Shailendra Kumar Singh, Fareeda Athar, Amir AzamAbstract:Abstract We report here the synthesis, characterization and in vitro Antiamoebic activity of 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones (TSC), 1 – 5 , and their bidentate complexes [Ru(η 4 -C 8 H 12 )(TSC)Cl 2 ] 1a – 5a . The biological studies of these compounds were investigated against HK - 9 strain of Entamoeba histolytica and the concentration causing 50% cell growth inhibition (IC 50 ) was calculated in the micromolar range. The ligands exhibited Antiamoebic activity in the range (2.05–5.29 μM). Screening results indicated that the potencies of the compounds increased by the incorporation of ruthenium(II) in the thiosemicarbazones. The complexes 1a – 5a showed Antiamoebic activity with an IC 50 of 0.61–1.43 μM and were better inhibitors of growth of E. histolytica , based on IC 50 values. The most promising among them is Ru(II) complex 2a having 1,2,3,4-tetrahydroquinoline as N 4 substitution.
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synthesis and Antiamoebic activity of 3 7 dimethyl pyrazolo 3 4 e 1 2 4 triazin 4 yl thiosemicarbazide derivatives
European Journal of Pharmaceutical Sciences, 2005Co-Authors: Shailendra Kumar Singh, Kakul Husain, Fareeda Athar, Amir AzamAbstract:A series of 3,7-dimethyl-pyrazolo[3,4-e][1,2,4]triazin-4-yl thiosemicarbazide derivatives 3-22 were prepared and evaluated in vitro against HM1:1MSS strain of Entamoeba histolytica, to identify the compounds for Antiamoebic activity. They exhibited Antiamoebic activity in the range (IC50=0.81-7.31microM). The results were compared to the activity of known drug metronidazole. It is inferred from the in vitro studies that the compounds 10, 11, 17 and 18 were found to be significantly better inhibitors of E. histolytica since IC50 values in the muM range elicited by these compounds are much lower than metronidazole. Besides, compounds 11 and 17 have shown the most promising Antiamoebic activity (IC50=0.81microM of 11, IC50=0.84 microM of 17 versus IC50=1.81microM of metronidazole). The study suggests the possibility of developing triazine analogues as potential drug candidates for Antiamoebic activity.
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synthesis characterization and in vitro Antiamoebic activity of 5 nitrothiophene 2 carboxaldehyde thiosemicarbazones and their palladium ii and ruthenium ii complexes
European Journal of Medicinal Chemistry, 2004Co-Authors: Shailendra Kumar Singh, Neelam Bharti, Fehmida Naqvi, Amir AzamAbstract:Synthesis of new Palladium(II) and Ruthenium(II) complexes of the type, [Pd(L)Cl(2)] and [Ru(eta(4)-C(8)H(12))(L)Cl(2)] [where, L = thiosemicarbazones derived from 5-nitrothiophene-2-carboxaldehyde and cycloalkylaminothiocarbonyl hydrazines] have been isolated by the reaction of [Pd(DMSO)(2)Cl(2)] and [Ru(eta(4)-C(8)H(12))(CH(3)CN)(2)Cl(2)] with 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones. The spectral data revealed that the thiosemicarbazones act as bidentate ligands, making use of thionic sulphur and the azomethine nitrogen atom for coordination to the central metal ion. Microdilution method was used for the assessment of Antiamoebic activity of all the compounds against HK-9 strain of Entamoeba histolytica. Among all the thiosemicarbazones, 5-NT-4-BPTSCN (3) showed significant Antiamoebic activity (IC(50) - 2.56 microM). Enhancement of Antiamoebic activity resulted by introducing palladium and ruthenium metals in the thiosemicarbazone moiety. All the Pd(II) and Ru(II) complexes of 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones were found more active then their respective ligands. The complexes 1a-4a, 1b and 3b showed Antiamoebic activity.