A Claisen-Schimidt condensation of 2-hydroxyacetophenones 1a-f with an aldehyde 2 yielded a series of compounds 3a-f. Compounds 3a-f were transformed into series of substituted chromones 4a-f, pyrazolines 5a-f and aurones 6a-f on treatment with DMSO/ I 2 , NH 2 NH 2 / EtOH and Hg(OAc) 2 / pyridine respectively. All these novel compounds were characterized by spectral techniques. All the compounds were screened for their antibacterial potential.

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Novel thiazol‐5‐ylpyrimidine derivatives were designed and synthesized. The chemical structures of all new synthesized compounds were assigned by studying their elemental analyses and spectral data (FT‐IR, 1HNMR, 13C NMR, and MS). The target compounds, 8 and 9a‐9d were evaluated for their antimicrobial activity in vitro against gram‐positive bacteria, Bacillus subtilis and Staphylococcus aureus, gram‐negative bacteria, Salmonella abony and Escherichia coli and fungi, Aspergillus flavus and Fusarium oxysporum. In particular, compounds 9a‐9c exhibited moderate to good activity against gram‐positive bacteria, S. aureus, gram‐negative bacteria, S. abony and fungus, Fusarium oxysporum in comparison with reference drugs.

Chalcones3a-fwere prepared by reacting thiophene containing pyrazolyl aldehyde (2) with different 2-hydroxy acetophenones 1a-f. The compounds3a-f were transformed into different Pyrazolines 4a-f. The formation of chromene derivatives 5a-f occurred from the cyclization of 3a-f, which were then transformed into pyrazole derivatives 6a-f. Newly synthesized compounds have promising antibacterial activity against S.typhii and S.aureus, while weak activity against B.subtilis and E.coli. Compounds 5d and 6d had significant antifungal action towardsA. niger, while most of the compounds were moderately active towards T.viride. Some of the synthesized compounds showed promising α-amylase inhibitory activity at 1 mg/mL concentration.

The complex of 3-formyl chromone derivative ligand with the Cu(II) complex was isolated in the solid form. Which have been characterized using FTIR spectrums. The FTIR spectrum shows bands for characteristic frequencies at 1604 cm-1 indicates C=O group, belongs to pyrone ring. The frequency at 510 to 596 cm-1 and band at 916 to 964 cm-1 indicates the M-O and M-O=C-in pyrone ring respectively. The UV-Vis spectroscopy shows that carbonyl of aldehyde group and carbonyl of pyrone ring of chromone of ligand shows n-π*and π-π* transition and complex shows electronic absorption at 369nm due to the 2 B 1 g → 2 B 2 g transition. Thermo Gravimetric Analysis (TGA) of complexes and ligand was carried out to determine the procedural and decomposition temperatures. The temperature range in which decomposition occurs in the range between 209°C to 350°C. The magnetic properties were determined from Gouy balance method. The number of unpaired electron found in complex of Cu(II)-3-formylchromone derivative was one and it has dsp2 hybridization. The complex is soluble in DMSO. The molar conductance of the complex are measured in DMSO at a concentration 10-3 M.The ligand and their copper complexes were screened for antimicrobial activities by the agar well diffusion technique using DMSO as solvent. The complexes were checked for their biological activity by using, Escherichia coli, and Bacillus subtilis bacteria.