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The aim of the present study was to evaluate the H2O2 scavenging activity of the ZnO2/β-CD as a biocompatible composite. Zinc peroxide was prepared via sonochemical approach. To synthesize a green composite, β-cyclodextrin was modified by citric acid (CA) and reacted with ZnO2 under ultrasonic irradiation. The prepared samples were characterized using XRD, SEM, TGA and FTIR analytical techniques. XRD analysis exhibited a typical pattern of ZnO2 and demonstrated the presence of citric acid and β-cyclodextrin in composite. The results of the catalytic assay showed that the ZnO2/CA-βCD composite displayed stronger capability to decompose H2O2 in comparison to ZnO2 particles (about seven times). It was attributed to increased adsorption capacity and solubility of composite due to the presence of citric acid and β-cyclodextrin. MTT assay studies confirmed the non-cytotoxic nature of ZnO2 particles and ZnO2/CA-βCD composite.

The three-component Hantzsch condensation of various aryl aldehydes, dimedone, and methyl 3-aminocrotonate was investigated in the presence of MCM-41-supported ZnNO3. The polyhydroquinoline products which were obtained under mild conditions and very easy workup were evaluated for anti-cancer activities against MCF-7, SK-BR-3, and HT-29 of breast and colon cancer cells. The fluorescence emission of some products was also studied and their optical parameters were reported.

The reaction of the free amine group in polyaryl-substituted imidazole structures with phenyl isocyanate or dimethyl acetylenedicarboxylate gave two new series of polyaryl-substituted imidazoles: biaryl ureas or vinyl esters, respectively. Besides their spectroscopic analysis, we explored the optical and electrochemical properties of these highly conjugated scaffolds. Comparing these properties in two categories of products yielded interesting results.

A series of 4-(1-azolyl)aniline derivatives (azole = imidazole, benzimidazole, pyrazole, 3-methylpyrazole, and 4-methylpyrazole) underwent diazotization reaction by NaNO2/HCl. The diazonium salts were consequently treated with aromatics such as phenol, N,N-dimethylaniline, 2-naphthol, and 8-hydroxyquinoline to give the coupled azo compounds. The antibacterial activities of some of the products were evaluated against Gram-negative [Escherichia coli (ATCC 25922)] and Gram-positive [Staphylococcus aureus (ATCC 25923)] bacteria. Moreover, in vitro examinations for a series of the products corroborated anticancer activities against MCF7 breast cancer cells.

A series of 2-(4-styrylphenyl)-1,4,5-triaryl imidazole derivatives have been efficiently synthesized through Wittig reactions starting with 2-[(4-bromomethyl)phenyl]-1,4,5-triarylimidazoles and been verified by spectroscopic data. The optical absorption and emission properties of the synthesized novel (E)-stilbene derivatives were examined in dilute ethanol solution. Most of the products exhibit a strongly enhanced fluorescence intensity.

A series of novel 1,2,3-triazole derivatives containing kojic acid moiety were synthesized by 1,3-dipolar cycloaddition reaction of 2-(azidomethyl)-5-hydroxy-4H-pyran-4-one and 2-(azidomethyl)-5-benzyloxy-4H-pyran-4-one with different alkynes in 41–99% yields. In the case of terminal alkynes, the reactions occurred in the presence of Cu(I) catalyst. The antioxidant activity of the synthesized compounds containing 5-hydroxyl group was evaluated by 1,1-diphenyl-2-picrylhydrazyl method.

Palladium-catalyzed cross-coupling reactions of 2,6-diaryl-3,5-dibromo-4-pyrones with imidazole and benzimidazole in the presence of N,N′-dibutylbenzimidazol-2-ylidene as ligand resulted in the formation of the monosubstituted C- and N-arylated products. Kojic acid was also treated with some aryl halides at the same conditions, to afford C-6 arylated derivatives.

A series of kojic acid benzyl ether derivatives possesing imidazole, benzimidazole, and pyrazole rings were synthesized by SN2'-substitution of these heterocycles using prepared Baylis–Hillman acetates.

A series of fused pyrimidone derivatives of 4-pyrones was synthesized by conversion of the acetates of Baylis−Hillman adducts obtained from 2-formyl-4-pyrones with 2-aminopyridine and 2-aminothiazole.