53278-53-8Relevant articles and documents
Synthesis and antiamoebic activity of 3,7-dimethyl-pyrazolo[3,4-e][1,2,4] triazin-4-yl thiosemicarbazide derivatives
Singh, Shailendra,Husain, Kakul,Athar, Fareeda,Azam, Amir
, p. 255 - 262 (2005)
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 (IC 50 = 0.81-7.31 μM). 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 μM range elicited by these compounds are much lower than metronidazole. Besides, compounds 11 and 17 have shown the most promising antiamoebic activity (IC50 = 0.81 μM of 11, IC50 = 0.84 μM of 17 versus IC50 = 1.81 μM of metronidazole). The study suggests the possibility of developing triazine analogues as potential drug candidates for antiamoebic activity.
Synthesis, spectral studies and antiamoebic activity of new 1-N-substituted thiocarbamoyl-3-phenyl-2-pyrazolines
Abid, Mohammad,Bhat, Abdul Roouf,Athar, Fareeda,Azam, Amir
scheme or table, p. 417 - 425 (2009/04/18)
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, 1H and 13C 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 IC50 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.
Antiamoebic coumarins from the root bark of Adina cordifolia and their new thiosemicarbazone derivatives
Iqbal, Prince Firdoos,Bhat, Abdul Roouf,Azam, Amir
experimental part, p. 2252 - 2259 (2009/09/30)
In continuation of our search for potential antiamoebic agents from folklore Indian medicinal plants, we found that the benzene and ethyl acetate extracts from the root bark of Adina cordifolia exhibited strong antiamoebic activity with IC50 values of 2.92 and 2.50 μg/ml, respectively. Bioassay-guided fractionation of benzene and ethyl acetate extracts led to the isolation of 7-hydroxycoumarin (umbelliferone 1) and 7-β-D-glucosylcoumarin (skimmin 2), respectively. Umbelliferone 1 was converted into 7-acetoxycoumarin 1a, which on treatment with aluminium chloride afforded 7-hydroxy-8-acetylcoumarin 2a. A new series of thiosemicarbazones 3a-e of 7-hydroxy-8-acetylcoumarin with different thiosemicarbazides were synthesized. Umbelliferone was also converted into its methoxy derivative (7-methoxycoumarin 4). Subsequently, all the compounds were assessed for antiamoebic activity against HM1:IMMS strain of Entamoeba histolytica. Umbelliferone and skimmin were found to possess a very good activity with IC50 values of 6.38 and 4.35 μM/ml, respectively. The activity drastically increased on converting compound 2a into its thiosemicarbazone derivatives 3a-e with IC50 values ranging between 1.06 and 4.46 μM/ml. Compounds 3b,c and e with IC50 values of 1.49, 1.56 and 1.06 μM/ml, respectively, exhibited even higher antiamoebic activity than the standard drug metronidazole (IC50 = 2.62 μg/ml). The activity of 7-methoxycoumarin (IC50 = 8.92 μM/ml) was less than umbelliferone. Compounds 3b, c and e were tested for toxicity using H9c2 cardiac myoblasts cell line. The compounds exhibit >80% viability at 3.125-200 μg/ml. It is apparent from these results that umbelliferone and skimmin may be a useful lead for the development of new antiamoebic drugs.
