A series of 6-amino-4-substituted-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles 5a–j were synthesized via one-pot, four-component condensation reactions of aryl aldehydes 1a–j, propanedinitrile (2), hydrazine hydrate (3) and ethyl acetoacetate (4) under solvent-free conditions. We report herein the use of the Brønsted acid ionic liquid (BAIL) triethylammonium hydrogen sulphate [Et₃NH][HSO₄] as catalyst for this multi-component synthesis. Compared with the available reaction methodology, this new method has consistent advantages, including excellent yields, a short reaction time, mild reaction conditions and catalyst reusability. Selected synthesized derivatives were evaluated for in vitro anticancer activity against four human cancer cell lines viz. melanoma cancer cell line (SK-MEL-2), breast cancer cell line(MDA-MB-231), leukemia cancer cell line (K-562) and cervical cancer cell line (HeLa). Compounds 5b, 5d, 5g, 5h and 5j exhibited promising anticancer activity against all selected human cancer cell lines, except HeLa. Molecular docking studies also confirmed 5b and 5d as good lead molecules. An in silico ADMET study of the synthesized anticancer agents indicated good oral drug-like behavior and non-toxic nature.

A novel series of 5-(4-(benzyloxy)substituted phenyl)-3-((phenyl amino)methyl)-1,3,4-oxadiazole-2(3H)-thione Mannich bases 6a–o were synthesized in good yield from the key compound 5-(4-(benzyloxy)phenyl)-1,3,4-oxadiazole-2(3H)-thione by aminomethylation with paraformaldehyde and substituted amines using molecular sieves and sonication as green chemistry tools. The antifungal activity of the new products was evaluated against seven human pathogenic fungal strains, namely, Candida albicans ATCC 24433, Candida albicans ATCC 10231, Candida glabrata NCYC 388, Cryptococcus neoformans ATCC 34664, Cryptococcus neoformans PRL 518, Aspergillus fumigatus NCIM 902 and Aspergillus niger ATCC 10578. The synthesized compounds 6d, 6f, 6g, 6h and 6j exhibited promising antifungal activity against the tested fungal pathogens. In molecular docking studies, derivatives 6c, 6f and 6i showed good binding at the active site of C. albicans cytochrome P450 enzyme lanosterol 14 α-demethylase. The in vitro antifungal activity results and docking studies indicated that the synthesized compounds have potential antifungal activity and can be further optimized as privileged scaffolds to design and develop potent antifungal drugs.

A series of ten novel derivatives of 4-(benzyloxy)-N-(3-chloro-2-(substituted phenyl)-4-oxoazetidin-1-yl) benzamide 6a–j were synthesized in good yield from the key compound 4-(benzyloxy)-N′-(substituted benzylidene) benzo hydrazide, called Schiff ’s bases 5a–j, by Staudinger reaction ([2 + 2] ketene-imine cycloaddition reaction) with chloro acetyl chloride in the presence of catalyst tri ethylamine and solvent dimethyl formamide (DMF), by using ultra-sonication as one of the green chemistry tools. All the synthesised compounds were evaluated for in vitro anti-tubercular activity against Mycobacterium tuberculosis (MTB) and most of them showed promising activity with an IC₅₀ value of less than 1 µg/mL. To establish the safety, all the synthesized compounds were further tested for cytotoxicity against the human cancer cell line HeLa and all 6a–j compounds were found to be non-cytotoxic in nature. The molecular docking study was carried out with essential enzyme InhA (FabI/ENR) of Mycobacterium responsible for cell wall synthesis which suggests that 6a and 6e are the most active derivatives of the series. The theoretical evaluation of cell permeability based on Lipinski’s rule of five has helped to rationalize the biological results and hence the synthesized azetidinone derivatives 6a–j were also analyzed for physicochemical evaluation that is, absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties and the results showed that all the derivatives could comply with essential features required for a potential lead in the anti-tubercular drug discovery process.

This work reports synthesis of ten novel derivatives of 5-(1-(substituted phenyl)-4,5-diphenyl-1H-imidazol-2-yl)-4-methylthiazole 5(a–o). The reaction of benzil, primary aryl amines, 4-methylthiazole-5-carbaldehyde and ammonium acetate was carried out in one pot in the presence of eco-friendly catalyst Ceric ammonium nitrate in solvent ethanol to give final compounds. The structures of the synthesized compounds were confirmed by spectral characterization such as IR, ¹H-NMR, ¹³C-NMR and mass spectral studies.

In the category of microorganism, fungi are considered as the special class of microbes responsible for opportunistic pathogenic infections in humans species. Due to the side effects of commercially available antifungal drugs and the emergence of new drug resistant fungal species in the past few years has forced the researchers to search for novel and efficient antifungal drug molecules. The 1,3,4-oxadiazoles scaffold is associated with diverse biological activities. The multipurpose use of the Mannich bases in pharmaceutical chemistry provoked us to prepare a new series of 1,3,4-oxadiazole Mannich bases derivatives, as antifungal agents. Herein we report Molecular sieves and Ultrasound assisted synthesis of novel series of Mannich bases of the 5-substituted 1,3,4-oxadiazole-2-thiones by amino methylation with paraformaldehyde and substituted primary / secondary amines and their evaluation for antifungal activity .The structures of the newly synthesized compounds were determined by IR, NMR and Mass spectral study. The synthesized compounds exhibited interesting moderate to excellent antifungal activity against Candida albicans (NCIM 3557),Candida albicans(NCIM3471), Candida glabrata(NCIM3237), Cryptococcus neoformans (NCIM 3542),Cryptococcus neoformans(NCIM 3378),Aspergillus fumigates(NCIM 902), Aspergillus niger( NCIM 628) using Flucanazole as a standard reference drug. The synthesised compounds 6d, 6f ,6g, 6h and 6j exhibited promising antifungal activity as fungi static agents.

: A series of 4-(benzyloxy)-N-(3-chloro-2-(substituted phenyl)-4-oxoazetidin-1-yl) benzamide 6a-j were synthesized in good yield from Schiff bases by cyclo-condensation with chloro acetyl chloride in the presence of catalyst tri ethylamine and solvent DMF by using ultra-sonication as one of the green chemistry tool. Synthesis of these derivatives by a conventional method like stirring at room temperature required 20–28 hr and by refluxing nearly takes 8–10 hr whereas using ultra-sonication it requires only 2h for completion of reaction. The use of ultrasound to promote chemical reactions is called sono-chemistry, it is complementary technique for promoting chemical reactions by ecofriendly green synthetic protocol. Ultrasound assisted synthesis are used to reduce the amount of undesired hazardous chemicals and solvents, reduce energy consumption and increase the selectivity towards the given product. Schiff bases are the compounds carrying imine or azomethine (–C=N–) functional group in which the electrophilic carbon and nucleophilic nitrogen confers the Schiff bases possibility to interact with several biological targets and have gained importance in medicinal and pharmaceutical fields exhibiting broad spectrum of biological activities. These key compounds 4-(benzyloxy)-N'-(substituted benzylidene) benzo hydrazide i.e Schiff bases 5a-j were obtained by condensation 4-(benzyloxy)benzo hydrazide with various aromatic aldehydes. The four-membered cyclic amides commonly known as 2-azetidinones or β-lactam occupy an eminent place in organic and medicinal chemistry since the structure of penicillin showed the presence of β-lactam ring in it and various potent activities of penicillin are due to the presence of β-lactam ring. Azetidinones are known to exhibit various biological activities like anti-tubercular, antibacterial and antifungal with β-lactam ring. Hence we are introducing the eco-friendly protocol for the synthesis of substituted azetidinone derivatives. All the synthesized compounds were characterized by FTIR, ¹HNMR, ¹³CNMR and mass spectral analysis.