Microwave induced synthesis of fluorobenzamides containing thiazole and thiazolidine as promising antimicrobial analogs

Design, Synthesis, and Biological Evaluation of Novel Thiazolidinone-Containing Quinoxaline-1,4-di-N-oxides as Antimycobacterial and Antifungal Agents

Tuberculosis and fungal infections can pose serious threats to human health. In order to find novel antimicrobial agents, 26 novel quinoxaline-1,4-di-N-oxides containing a thiazolidinone moiety were designed and synthesized, and their antimycobacterial activities were evaluated. Among them, compounds 2t, 2u, 2y, and 2z displayed the most potent antimycobacterial activity against Mycobacterium tuberculosis strain H37Rv (minimal inhibitory concentration [MIC] = 1.56 μg/mL). The antifungal activity of all the compounds was also evaluated against Candida albicans, Candida tropicalis, Aspergillus fumigatus, and Cryptococcus neoformans. Compounds 2t, 2u, 2y, and 2z exhibited potential antifungal activities, with an MIC between 2 and 4 μg/mL. Comparative molecular field analysis (CoMFA: q² = 0.914, r² = 0.967) and comparative molecular similarity index analysis (CoMSIA: q² = 0.918, r² = 0.968) models were established to investigate the structure and antimycobacterial activity relationship. The results of contour maps revealed that electronegative and sterically bulky substituents play an important role in the antimycobacterial activity. Electronegative and sterically bulky substituents are preferred at the C7 position of the quinoxaline ring and the C4 position of the phenyl group to increase the antimycobacterial activity. Additionally, more hydrogen bond donor substituents should be considered at the C2 side chain of the quinoxaline ring to improve the activity.

s-Proline Covalented Silicapropyl Modified Magnetic Nanoparticles: Synthesis, Characterization, Biological and Catalytic Activity for the Synthesis of thiazolidin-4- ones

BACKGROUND

Thiazolidinoneones are important pharmaceutical compounds because of their biological activities. Several methods for the synthesis of 4-thiazolidinones are widely reported in the literature. The main synthetic routes to synthesize 1,3-thiazolidin-4-ones involve three components reaction between amine, a carbonyl compound and thioglycolic acid.

OBJECTIVE

s-Proline covalented silicapropyl modified magnetic nanoparticles (Fe3O4@SiO2-Pr @s-proline) were prepared. The antibacterial activity of synthesized nanoparticles against four bacterias was investigated that showed that 30 Mg/L of synthesized nanoparticles is a suitable concentration for bacterial inhibitory. Finally, the catalytic application of the synthesized s-Proline covalented silicapropyl modified magnetic nanoparticles for the synthesis of thiazolidinones and pyrazolyl thiazolidinones under stirring in aqueous media was evaluated. All of the synthesized organic compounds were characterized by mp, FT IR, 1H NMR, 13C NMR and elemental analysis.

MATERIALS AND METHODS

A combination of aldehyde (1.0 mmol), thioglycolic acid (1.0 mmol), various amines (1mmol) and 0.05 g Fe3O4@SiO2propyl@L-proline, were reacted at room temperature under stirring in 10 mL water. After completion of the reaction, as indicated by TLC (4:1 hexane: ethylacetate), the reaction mixture was filtered in the presence of an effective magnetic bar to separate the nanocatalyst. The nanocatalyst was washed with a mixture of hot EtOH: H2O two times. The crude products were collected and recrystallized from ethanol, if necessary.

RESULTS AND DISCUSSION

We present a novel avenue for the synthesis of thiazolidinones in the presence of Fe3O4@SiO2-Pr @s-proline under solvent-free conditions.

CONCLUSION

In conclusion, we have synthesized Fe3O4@SiO2-Pr@s-proline nanoparticles. Their biological activity against 4 bacterias was investigated. It released that 30Mg/L is the suitable concentration of synthesized nanoparticle for bacterial inhibitory. The catalytic efficiency of the catalyst was checked in the multicomponent reaction of various aldehyde, thioglycolic acid and various amines under stirring. This nanoparticle is a new organic-inorganic hybrid nanoparticle. The operational simplicity, the excellent yields of products, ease of separation and recyclability of the magnetic catalyst, waste reduction and high selectivity are the main advantages of this catalytic method. Furthermore, this new avenue is inexpensive and environmentally benign.

Urazolium diacetate as a new, efficient and reusable Brønsted acid ionic liquid for the synthesis of novel derivatives of thiazolidine-4-ones

Urazolium diacetate catalyzed synthesis of new derivatives of 1,3-thiazolidine-4-ones (azo dispersive dyes family)viamulticomponent reaction of various aldehydes, thioglycolic acid and 4-aminoazobenzene under solvent-free reaction was reported.

Design, synthesis and biological evaluation of some novel sulfonamide derivatives as apoptosis inducers

Several novel thiazolidinone and fused thiazolidinone derivatives bearing benzenesulfonamide moiety were synthesized and confirmed via spectral and elemental analyses. The newly synthesized compounds were evaluated for their cytotoxic activity on colorectal cancer cell line (Caco-2). All the synthesized compounds showed better activity than the reference standards (Doxorubicin and 5-FU). Investigation of the apoptotic activity of the most active compounds revealed that compounds 3a, 5a, 5c and 6c activate both caspase-3 and Fas-ligand in Caco-2 cell line. Compound 3a was the most active compound with caspase-3 concentration of 0.43 nmol/mL and Fas-ligand concentration of 775.2 pg/mL in treated Caco-2 cells. Compound 3a was radiolabeled with ^99mTc and its biodistribution pattern was evaluated in vivo using normal Swiss Albino mice. ^99mTc-compound 3a complex didn't exhibit any accumulation in any body organs except for its accumulation in the colon; target organ; where it showed 8.97 ± 1.35 %ID/g at 15min p. i. that elevated till 16.02 ± 2.43 %ID/g at 120min p. i.

A facile synthesis and antimicrobial activity evaluation of sydnonyl-substituted thiazolidine derivatives

Some new sydnonyl-substituted thiazolidine derivatives were synthesized in high yields by the modified Knoevenagel condensation of 3-aryl-4-formylsydnones with thiazolidine-2,4-dione and 2-thioxo-thiazolidine-4-one, respectively. All the synthesized thiazolidine derivatives were screened by paper-disc method to identify their antimicrobial activities against three bacteria viz. Staphylococcus aureus, Proteus vulgaris and Escherichia coli, and two fungal cultures viz. Aspergillus niger and Penicillium citrinum. The reference drugs were Norfloxacin and Griseofulvin, respectively. The screening data indicated that the tested sydnonyl-substituted thiazolidine derivatives exhibited no obvious antibacterial activity compared with the standard drug Norfloxacin. However, thiazolidine derivatives displayed significant antifungal activities against Penicillium citrinum and Aspergillus niger. Notably, all of the tested compounds showed growth inhibitory activity 1.5-4.4 times higher than that of the standard drug Griseofulvin against the two fungi.

Synthesis, antimicrobial and cytotoxic activities of some novel thiazole clubbed 1,3,4-oxadiazoles

A series of thiazole clubbed 1,3,4-oxadiazole derivatives (5a-l) have been synthesized and characterized by IR, (1)H NMR, (13)C NMR and mass spectral analysis. Synthesized compounds were evaluated for their antimicrobial and cytotoxic activities. The results indicated that, compounds 5c and 5i exhibited the most potent antibacterial activity. Compound 5f was found to be the most potent antifungal agent. The structure activity relationship revealed that the presence of electron withdrawing groups at para position of phenyl ring remarkably enhanced the antibacterial activity of synthesized compounds. Further, the results of preliminary MTT cytotoxicity studies on HeLa cells suggested that potent antimicrobial activity of 5b, 5c, 5f, 5h and 5i is accompanied by low cytotoxicity.