Synthesis and biological evaluation of novel 5-aryl-4-(5-nitrofuran-2-yl)-pyrimidines as potential anti-bacterial agents

Synthesis of new 2-(5-(5-nitrofuran-2-yl)-1,3,4-thiadiazol-2-ylimino)thiazolidin-4-one derivatives as anti-MRSA and anti-H. pylori agents

In this work, we have synthesized twenty five new 2-(5-(5-nitrofuran-2-yl)-1,3,4-thiadiazol-2-ylimino)thiazolidin-4-one derivatives bearing an aryl or heteroaryl methylene group on position 5 of thiazolidinone and evaluated their antimicrobial activity against Gram-positive and -negative bacteria as well as three metronidazole resistant Helicobacter pylori strains. Most of the compounds were very potent towards tested Gram-positive bacteria and showed an antibacterial efficacy substantially greater than ampicillin as the reference drug. However, no effectiveness was observed for the Gram-negative microorganisms. The compounds 9, 20 and 29 exhibited strong antimicrobial activity against Helicobacter pylori strains (inhibition zone > 30 mm) in 100 μg/disc and (inhibition zone > 20 mm) in 50 μg/disc. Taking these findings together, it seems that these potent antibacterial derivatives could be considered as promising agents for developing new anti-infectious drugs against microorganisms resistant to currently available antibiotics.

Synthesis of N-Pyrrolyl(furanyl)-Substituted Piperazines, 1,4-Dizepanes, and 1,4-Diazocanes

The synthetic potential of 5-bromo-1,1,1-trifluoro-4-methoxypent-3-en-2-one toward the catalyst-free synthesis of N-pyrrolyl(furanyl)-piperazines, 1,4-diazepanes, and 1,4-diazocanes through a telescoped protocol is reported. This three-component one-pot method provided 23 examples with high chemo- and regioselectivity at yields up to 96%.

Current development of 5-nitrofuran-2-yl derivatives as antitubercular agents

Pulmonary tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (MTB) and still remains one of the foremost fatal infectious diseases, infecting nearly a third of the worldwide population. The emergencies of multidrug-resistant and extensively drug-resistant tuberculosis (MDR and XDR-TB) prompt the efforts to deliver potent and novel anti-TB drugs. Research aimed at the development of new anti-TB drugs based on nitrofuran scaffold led to the identification of several candidates that were effective against actively growing as well as latent mycobacteria with unique modes of action. This review focuses on the recent advances in nitrofurans that could provide intriguing potential leads in the area of anti-TB drug discovery.

A new efficient domino approach for the synthesis of coumarin-pyrazolines as antimicrobial agents targeting bacteriald-alanine-d-alanine ligase

The inhibition ofd-alanine-d-alanine ligase (Ddl) prevents bacterial growth, which makes this enzyme an attractive and viable target in the urgent search for novel effective antimicrobial drugs.

Design, synthesis and evaluation of oxime-functionalized nitrofuranylamides as novel antitubercular agents

A series of oxime-functionalized nitrofuranylamides were designed, synthesized and evaluated for their in vitro anti-mycobacterial activities against MTB H37Rv and drug-resistant clinical isolates. Among them, two compounds 7a and 7b exhibited excellent activity against the three tested strains. Both of them were comparable to the first-line anti-TB agents INH and RIF against MTB H37Rv, and were far more potent than INH and RIF against MDR-TB 16833 and 16995 strains. Thus, both of them could act as leads for further optimization.

Microwave-assisted synthesis, computational studies and antibacterial/ anti-inflammatory activities of compounds based on coumarin-pyrazole hybrid

An efficient, high-yield and rapid synthesis of (E)-1,5-dimethyl-4-((2-((substituted-2-oxo-2H-chromen-4-yl)methoxy)naphthalen-1-yl)methyleneamino)-2-phenyl-1,2-dihydropyrazol-3-one derivatives (3a-3i) containing Schiff base structures under microwave-irradiation has been described. Schiff base is a potential target to discover anti-inflammatory chemotherapeutics, material science, catalysis and molecular magnetism. All the newly synthesized compounds (3a-3i) have been characterized by elemental analysis and spectroscopic techniques. The synthesized compounds (3a-3i) were evaluated for their antibacterial activity by agar-well diffusion method and anti-inflammatory activity by egg albumin denaturation method. The compounds (3e) and (3i) exhibit antibacterial effect with minimum inhibitory concentration (MIC) 0.78 µg ml^-1 and MIC 1.562 µg ml^-1 against Gram-positive Staphylococcus aureus bacterial strain compared with standard ciprofloxacin drug (MIC 6.25 µg ml^-1). The compounds (3c) and (3f) exhibited an inhibition of heat-induced protein denaturation at the concentration (31.25 µg ml^-1) as 53.65% and 67.27%, respectively, and these compounds are more active than standard aceclofenac drug (5.50%). Molecular docking study has been performed for all the synthesized compounds with S. aureus dihydropteroate synthetase and results obtained are quite promising.

5,6-Dihydropyrimidine-1(2H)-carbothioamides: Synthesis, in vitro GABA-AT screening, anticonvulsant activity and molecular modelling study

Even after considerable advances in the field of epilepsy treatment, convulsions are inefficiently controlled by standard drug therapy. Herein, a series of pyrimidine-carbothioamide derivatives 4(a-t) was designed as anticonvulsant agents by doing some important structural modifications in well-known anticonvulsant drugs. Two classical animal models were used for the in vivo anticonvulsant screening, maximum electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) models; followed by motor impairment study by rotarod method. The most active compound 4g effectively suppressed seizure effect in both the animal models with median doses of 15.6 mg/kg (MES ED₅₀), 278.4 mg/kg (scPTZ ED₅₀) and 534.4 mg/kg (TD₅₀) with no sign of neurotoxicity. Furthermore, in vitro GABA-AT enzyme activity assay of 4g showed inhibitory potency (IC₅₀) of 12.23 μM. The docking study also favored the animal studies.