New thiobarbituric acid scaffold-based small molecules: Synthesis, cytotoxicity, 2D-QSAR, pharmacophore modelling and in-silico ADME screening.

A series of twenty five new thiobarbituric acid derivatives, viz. 3a-h, 4-7, 8a-c, 9, 10a-c, 11 and 12a-d, were designed and synthesized as potential cytotoxic agents. In-vitro screening of the new compounds against the three human cancer cell lines Caco-2, HepG-2 and MCF-7 was performed to assess their intrinsic activity. Compound 12d exhibited potent sub-micromolar activity against HepG-2 and MCF-7 (IC50 = 0.07 and 0.08 µM, respectively). In-silico pharmacophore modelling of this chemotype compounds disclosed a five features' pharmacophore model representing essential steric and electronic fingerprints essential for activity. Finally, a 2D-QSAR model was devised to quantitatively correlate the 2D molecular feature descriptors of this series of thiobarbiturates with their cytotoxic activity against MCF-7. Finally, in silico evaluation of the physicochemical and ADME properties of these derivatives was performed.

Synthesis of new pyrrolo[2,3-d]pyrimidine derivatives as antibacterial and antifungal agents.

A series of new pyrrole derivatives, pyrrolo[2,3-d]pyrimidine derivatives, pyrrolotriazolopyrimidines and pyrrolotetrazolopyrimidines were synthesized. The evaluation of their antimicrobial activities against Staphylococcus aureus, Escherichia coli, and Candida albicans were carried out. Pyrrolo[2,3-d]pyrimidines 3a-d, 7a,e, 11d exhibited excellent activity against C. albicans with MIC 0.31-0.62 mg/mL. These compounds displayed better antifungal activity than that of standard drug (fluconazole with MIC 1.5 mg/mL). Furthermore, pyrrolo[2,3-d]pyrimidines 3b,c, 7e exhibited the best activity against S. aureus with MIC 0.31 mg/mL, compared with the standard drug (ampicillin with MIC 0.62 mg/mL). The rest of the compounds were found to be inactive against bacteria and fungi.

Synthesis and biological evaluation of novel imidazolone derivatives as potential COX-2 inhibitors.

Three novel series of 2-(substituted phenyl)-4-(substituted arylidene)-imidazolone-5-(4H)-ones were derived from the corresponding oxazolones by condensation with different arylamines. Eleven of the synthesized compounds were selected and evaluated for their effect on carrageenan-induced rat paw edema. Compound 4b had the same efficacy as the reference standard (indomethacin), and compounds 3b, 3c, 4a, 4d and 9a showed good to excellent activities, with other compounds only weakly active. The potent compounds were evaluated for their inhibitory activities against COX-2-catalyzed PGE(2) production, with 4a, 4b and 3c showing strong inhibitory activity.

Synthesis of new imidazolyl acetic acid derivatives with anti-inflammatory and analgesic activities.

We synthesized 2-(4-(4-fluorobenzylidene)-2-(4-fluorophenyl) 5-oxo-4,5-dihydroimidazol-1-yl) acetic acid 3. Chlorination afforded the chloro derivative 4, which reacted with different amines and hydrazine to afford compounds 5-8. Pyrazole, pyrazolone, and thiazolidinone derivatives were also synthesized from Imidazol-1-ylacetic acid hydrazide 8 to give compounds 9-12. Compounds were then evaluated for their anti-inflammatory activity against carrageenan-induced rat paw edema and their analgesic activity using the writhing test in albino mice. Compounds 5, 9, 10, 12 exhibited maximum anti-inflammatory activity, and all the compounds inhibited writhing, with 10 and 12 being two times more effective than the reference standard.