Synthesis and biological evaluation of pyrazole analogues linked with 1,2,3-triazole and 4-thiazolidinone as antimicrobial agents

A new series of 2-[3-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-4-pyrazolyl]-3-aryl-1,3-thiazolan-4-one 5(a-i) have been designed, synthesized and evaluated for their in vitro antibacterial activity against Gram positive bacteria viz. Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 6538p), Micrococcus luteus (IFC 12708) and Gram negative bacteria viz. Proteus vulgaris (ATCC 3851), Salmonella typhimurium (ATCC 14028), Escherichia coli (ATCC 25922) the antifungal activity against Candida albicans (ATCC 10231), Aspergillus fumigatus (HIC 6094), Trichophyton rubrum (IFO 9185), Trichophyton mentagrophytes (IFO 40996). Antibacterial evaluation indicates that compounds containing 4-methoxyphenyl 5c, 4-fluorophenyl 5d and 2,5-difluorophenyl 5h groups on thiazolidinone ring showed significant activity equal to that of standard drug. The antifungal evaluation shows that compound 5c is highly active against A. fumigatus, compound 5d and 5h were also active against C. albicans and A. fumigatus.

Synthesis, characterization, and antibacterial activity of azodyes incorporated acridine chromophore and their applications in polyester printing

A series of azo dyes incorporated acridine chromophore labelled as 8 (a-d), 10 (a, b), 12 and 14 were prepared in very good yields starting from 9-chloroacridine 1 followed by amination, diazotization and coupling either with rhodanine analogues 6 (a, b) or other coupling partners 9 (a, b), 11 and 13. FT-IR, 1H NMR, and mass spectroscopic analysis were used to establish the structures of the produced azo dispersed dyes. Moreover, the synthesized azo dyes were used to prepare pastes that were used to print polyester fabric using classic silk-screen printing techniques. The dyes were tested for color strength and fastness properties, and they showed good fastness resistance to washing, rubbing, and perspiration, as well as fastness to sublimation and light. The dyes were further screened for their in vitro antibacterial activity against both Gram (+) and Gram (-) bacterial species. Most of them showed promising activities against these tested organisms.

Green synthesis, characterization, biological evaluation and docking study of some pyrazoline and pyrimidine derivatives

Green and classical techniques have been utilized for preparing of a variety of aryl - substituted pyrazoline and pyrimidine derivatives (2-8). Reactions of chalcones 1 with semicarbazide and thiosemicarbazide, nicotinic acid hydrazide and amino guanidine hydrochloride afforded the corresponding N-substituted pyrazoline derivatives 2-5. Pyrimidine derivatives 6-8 were achieved via reaction of chalcone derivatives 1 with several reagents namely: guanidine nitrate, thiourea and 6-amino-2-thioxo-2,3- dihydropyrimidin-4(1H)-one under conventional and ultrasonic conditions. Ultrasonic method was found to be an easy work-up procedure and it gave high yield in comparison with conventional method. The structures of new synthesis compounds were characterized by elemental and spectral analyses. Some of newly compounds were tested in vitro antibacterial activity against some gram–positive and gram–negative. The antimicrobial results displayed favorable antimicrobial activity. Molecular docking has been perfomed for compound 5b using MOE 2008.10, The data results obtained are quite promising.

Ciprofloxacin-Loaded Gold Nanoparticles against Antimicrobial Resistance: An In Vivo Assessment

Metallic nanoparticles, such as gold nanoparticles (AuNPs), have been extensively studied as drug delivery systems for various therapeutic applications. However, drug-loaded-AuNPs have been rarely explored in vivo for their effect on bacteria residing inside tissues. Ciprofloxacin (CIP) is a second-generation fluoroquinolone with a broad-spectrum of antibiotic properties devoid of developing bacteria resistance. This research is focused on the synthesis and physical characterization of Ciprofloxacin-loaded gold nanoparticles (CIP-AuNPs) and their effect on the colonization of Enterococcus faecalis in the liver and kidneys of mice. The successfully prepared CIP-AuNPs were stable and exerted enhanced in vitro antibacterial activity against E. faecalis compared with free CIP. The optimized CIP-AuNPs were administered (500 µg/Kg) once a day via tail vein to infected mice for eight days and were found to be effective in eradicating E. faecalis from the host tissues. Moreover, unlike CIP, CIP-AuNPs were non-hemolytic. In summary, this study demonstrated that CIP-AuNPs are promising and biocompatible alternative therapeutics for E.-faecalis-induced infections resistant to conventional drugs (e.g., beta-lactams and vancomycin) and should be further investigated.

Design, Synthesis and Characterization of Thiophene Substituted Chalcones for Possible Biological Evaluation

Development of new antimicrobial agents is a better solution to rectify drug resistance problems in society. In this circumstances new functionalized sulphur bearing heterocyclic moiety were designed, synthesized and evaluated for their in vitro antibacterial activity. The present work encompasses the designing novel series of thiophene substituted analogous linked to para amino acetophenone and different aldehydes were successfully synthesized and biological activity was predicted using various computational software’s such as Chemsketch, Molinspiration, and admetSAR. Among the synthesized thiophene substituted chalcones T-IV-I and thiophene T-IV-B displayed significant activity against Streptococcus auresis. Compounds T-IV-J, T-IV-H and T-IV-C bearing sulphur moiety possess better activity against Staphylococcus aureus. Moreover T-IV-C and T-IV-J exhibits good antibacterial activity against E. coli and Pseudomonas aeruginosa. In general, most of the synthesized compounds exhibited remarkable antibacterial activity due to the presence of sulphur atom in the heterocyclic moieties as well as its lipophilic characters. Molecular docking studies indicated that the synthesized compounds are potent inhibitor of microsomal enzyme Glutathione-S-transferases (PDB ID: 1GNW) also find the different interacting residues, bond distanceand nature of bondingbetween the target and the ligand molecules. The results provide important information for the future design of more effective antibacterial agents.