A three-step method for obtaining pyrrolo[1,2-a]pyrazine-4,7-dicarboxylates was presented. The method involves the N-alkylation of 5-formylpyrrole-3-carboxylates with bromoacetate, followed by the aminoalkenylation of the N-alkoxycarbonylmethyl group using dimethylformamide di-tert-butyl acetal, and further annulation of the pyrazine ring in the presence of ammonium acetate. Procedures for selective hydrolysis, halogenation, arylation, and alkynylation of the synthesized dicarboxylates were described. The in silico evaluation of the potential bioactivity of the synthesized dicarboxylates 4a–f, dicarboxylic acids 7a–c,e, halogenated dicarboxylates 8f–j, and dicarboxylic acids 10a–e was carried out. As seen from the screening of antimicrobial activity, the synthesized compounds 7a–e, 8c,f–j, 10a–e exhibit inhibitory and bactericidal activity against several bacteria and fungi. The highest activity against Klebsiella pneumonia, Staphylococcus aureus, and Bacillus subtilis has been established for the compound 8f with a MIC of 15.625 µg/mL, and the highest antifungal activity against Candida albicans was found for the compounds 8f, 8g, and 8i (МІС=15.625 µg/mL). The molecular docking data show that the compound 8i has the highest affinity to the ThiM Klebsiella pneumoniae kinase, and compounds 8i, 8j are noted for their highest affinity to the DNA gyrase from Staphylococcus aureus.

A series of new benzimidazole phosphonate derivatives was obtained via nucleophilic addition of triethyl phosphite to the imine of the imidazole subgroup under solvent-free conditions. Structures of the formed products were confirmed using spectroscopic data (ATR-FTIR, ¹H-NMR, ¹³C-NMR, and MS). The antimicrobial profiles of the synthesized compounds were examined, and promising activities against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were revealed, showing significant inhibition zone diameters ranging from 13 to 17 mm. Alongside these experimental findings, in silico investigations were conducted using ADMET characteristics, which showed a positive pharmacokinetic profile and provided valuable information on potential interactions with target molecules. Besides, docking studies against tested microorganisms revealed further insights on the compounds’ binding interactions with the active sites. Finally, DFT analysis was performed to shed light on the synthesis of novel molecules.

We have synthesized all drugs using previously identified active pharmacophores through molecular hybridization. This paper explains a simple method for making N-((2-(piperazine-1-yl)-2,3-dihydro-1H-benzo[d][1,2,3]triazol-1-yl)methyl)aniline analogs 5(A–L) through steps. We used mass spectrometry, ¹H NMR, and ¹³C NMR to do a spectrum analysis to confirm the structure of the synthesized end products. We evaluated all synthesized compounds for their in vitro antimicrobial, antimalarial, and antitubercular activities. We have also examined the research on structure-activity relationships (SAR). Target chemicals demonstrate significant effectiveness against bacteria, fungal diseases, and malaria.

A number of 3-aryl-5,6-dihydroimidazo[2,1-b][1,3]thiazoles were synthesized by cyclocondensation of imidazolidine-2-thione with phenacyl bromides, and their antimicrobial and antioxidant activity was evaluated. Bioscreening confirmed the moderate antibacterial activity against the reference strains of bacteria Staphylococcus aureus, Escherichia coli and Proteus vulgaris and excellent antifungal activity against Candida albicans. It was found that 3-(4-chlorophenyl)-5,6-dihydroimidazo[2,1-b]thiazole 4h (MIC = 15.625 μg/ml) has twice the antifungal effect compared to the control drug Furacilin. The study of the antioxidant activity of the synthesized compounds proved their ability to inhibit 60–97% of DPPH radicals. The best antiradical effect was found for 4-(5,6-dihydroimidazo[2,1-b]thiazol-3-yl)phenol 4e (I = 97%). A probable mechanism of its action was proposed involving the formation of a radical cation by the SET process. For the most active antioxidants 4e-g, reactivity and electrostatic surface potential were evaluated using the DFT method, and molecular docking was studied on the human peroxiredoxin 5 protein model.

A series of new 4-(1,3,4-thiadiazol-2-yl)-containing polysubstituted pyrroles 3 a-k has been synthesized by a preparative convenient method from ethyl 5-chloro-4-formyl-1H-pyrrole-3-carboxylates 1 a-e, which were selectively transformed into the corresponding polysubstituted pyrrole-4-carboxylic acids 2 а-е using sodium hypochlorite as an oxidizer. Further, they were transformed into the target compounds with a high yield using the cyclocondensation with N-mono- or N,N-disubstituted thiosemicarbazides in the boiling phosphorus trichloroxide. As seen from the screening of antimicrobial activity, the synthesized compounds exhibit the inhibiting and bactericide activity against some bacteria and fungi. The highest activity has been established for the compounds 3 a, c, e-h, j against the strain Klebsiella pneumoniae (МІС=31.25 µg/mL). The calculated HOMO energy level proves that the compound 3 с is the most reactive ligand for the interaction with a protein receptor. The molecular docking data show that the compound 3 h has the highest affinity to the ThiM Klebsiella pneumoniae kinase.

A sequence of thioxotetrahydropyrimidenes derivatives, N-(4-chloro/methoxyphenyl)-3-formyl-6-methyl-4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxamides (4a-l) were synthesized by the formylation of N-(4-chloro/methoxyphenyl)-6-methyl-4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxamides (3a-l) by dry dimethyl formamide (DMF) and phosphorous oxychloride at room temperature. Formerly, compounds (3a-l) were synthesized by the condensation of N-(4-chloro/methoxyphenyl)-3-oxobutanamide (1), various aromatic aldehydes (2a-f) and thiourea with catalytic amount of concentrated hydrochloric acid under reflux temperature. The structures of the synthesized various thioxotetrahydropyrimidenes have been characterized by using elemental analysis, Infrared, ¹H-NMR, ¹³C-NMR spectroscopy and further supported by Mass spectroscopy. All the products have been screened for their in-vitro biological assay like antibacterial activity towards Gram-positive and Gram-negative bacterial strains and antifungal activity towards Aspergillus niger at a concentration of 40 µg/ml. It was showing that the compounds 4a, 4e, 4g, 4h, 4i and 4l displayed inspirational antibacterial and antifungal activity compared to the used reference standard.

3-aryl-6-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines were obtained with good yields (81-95%) via the heterocyclization reaction of 1-phenyl-2-((5-aryl-1,3,4-oxadiazole-2-yl)thio)ethane-1-ones in acetic acid. The physicochemical characteristics of the synthesized compounds were established, the structures were confirmed by the data of IR, ¹H and ¹³C NMR spectra, as well as the results of X-ray diffraction analysis. The cytotoxic, antibacterial and antifungal properties of these compounds were evaluated. In vitro screening results showed that compounds 8, 9 and 12 significantly inhibit (54-65%) the growth of HeLa, HBL-100 and CCRF-CEM cancer cell lines. It was found that the cytotoxicity of the synthesized compounds increases in the series of oxadiazoltiones (1-4) - S-derivatives (5-8) - triazolothiadiazines (9-12). Compounds 5-16 do not exhibit antimicrobial properties.

Bagasse and wheat bran are agrowaste and cause different environmental problems. These compounds contain highly valuable compounds that can be recycled by microorganisms. This work was carried out to evaluate the effect of fermentation by Bacillus subtilis on biological activity and chemical components of bagasse and wheat bran. The results demonstrated the antimicrobial activity of fermented wheat bran and bagasse against eight selected microbial pathogens exhibited high activity of fermented wheat bran and mix, fermented bagasse showed less antimicrobial activity. Fermented wheat bran and bagasse samples had the highest antioxidant activity values (16.45 and 14.94 %) in comparison with the unfermented samples (6.20 and 3.97 %) respectively. Concentration of protein, ash, oil, and carbohydrates in fermented wheat bran were 5.34 %, 7.30%, 2.36% and 10.6%, whereas in bagasse they were 2.45%, 1.68%, 1.51% and 3.25 respectively. The moisture contents in bagasse 73.1% were more than in wheat bran 63.88%.

A series of isoxazole derivatives, 3-aryl-5-[5-(4-nitrophenyl)-2-furyl]-2,3-dihydroisoxazoles (5a-j) were synthesized by cyclocondensation reaction between 1-aryl-3-[5-(4-nitrophenyl)-2-furyl]prop-2-en-1-ones (4a-j) and hydroxylamine hydrochloride in presence of sodium acetate in glacial acetic acid at reflux temperature. Formerly, compounds (4a-j) were synthesized by the condensation of 5-(4-nitrophenyl) furan-2-carbaldehyde (3) with various aromatic ketones by using alkali as catalyst. The structures of the synthesized various isoxazole have been characterized by using elemental analysis, Infrared,¹H-NMR spectroscopy and further supported by Mass spectroscopy. All the products have been screened for their in-vitro biological assay like antibacterial activity towards Gram-positive and Gram-negative bacterial strains and antifungal activity towards Aspergillus niger at a concentration of 40 µg/ml. It was exposed that the compounds 5a, 5c, 5e, 5f, and 5i showed inspiring antibacterial and antifungal activity compared to the used reference standard.

The synthesis, anticancer and antimicrobial properties of novel N-aryl-2-(5-aryltetrazol-2-yl)acetamides were discussed. Novel N-aryl-2H-tetrazoles were synthesized and modified in order to obtain the compounds with a satisfactory pharmacological profile. The structures of target substances were confirmed by using ¹H spectroscopy, mass spectrometry and elemental analysis. Anticancer activity screening was carried out within the framework of Developmental Therapeutic Program of the National Cancer Institute's (DTP, NCI, Bethesda, Maryland, USA). The compounds with significant levels of anticancer activities have been found that can be used for further optimization. The antimicrobial activity of the synthesized substances was evaluated by the value of the MIC and minimum fungicidal and bactericidal concentration. The findings exhibited that the compounds possessed moderate antimicrobial potential.