Ozlem Temiz-Arpaci

Objective: Many investigations are conducted in the battle against infectious diseases in order to develop new drug-active ingredient candidate compounds and to identify leading compounds. The goal of this study was to synthesis a total of seven compounds, six of which are novel, with the general structure 2-(4-tert-butylphenyl)-5-(4-substitutedphenylsulfonamido)benzoxazole, to elucidate their structures, and to test their antimicrobial activities using the microdilution method. Material and Method: The synthesis of the compounds was carried out in two stages. In the first stage, under PPA catalyst 2,4-diaminophenol and 4-tert-butylbenzoic acid were refluxed, and target compounds were produced in the second step by reacting 4-substitutedbenzenesulfonyl chloride with 5-Amino-2-(4-tert-butylphenyl)benzoxazole. The compounds' antimicrobial activity was determined by using Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and drug-resistant strains of these microorganisms in vitro antimicrobial activity studies. Furthermore, estimated ADME profiles were calculated using the SwissADME online software. Result and Discussion: The structures of the synthesized compounds were elucidated using 1H-NMR, 13C-NMR and Mass spectroscopy, and also their melting points were determined. The antimicrobial activities of the compounds ranged from 64 µg/ml to ˃512 µg/ml and were weaker than the reference drugs. The best antimicrobial activity was reported against an isolate of E. faecalis, with all compounds having MIC values of 64 µg/ml. The fact that six of the seven synthesized compounds are novel and that their antimicrobial activity will be tested for the first time will make a significant contribution to studies to develop new or alternative antimicrobial agents.

Spectroscopic properties and DFT studies (optimized geometry, vibrational band assignment, MEP analysis, frontier molecular orbitals, NLO effects, and thermodynamic functions) of...

Breast cancer today is the most frequent cancer among women, and the second most common cause of cancer deaths among women. The aim of this study was to synthesize a new benzoxazole derivative, scan it for anti-cancer potential by MTT test using different breast cancer cell lines, and examine its effects on NF-κB and apoptosis related proteins by the western blot method. A newly synthesized benzoxazole derived compound was applied to cancer cell lines and its cytotoxicity was measured quantitatively by MTT test. Later, the level of its effects on NF-κB and apoptosis related proteins were examined. The structure of the compound synthesized in our study (5-amino-2-(p-bromobenzyl) benzoxazoleand 5-[4-chlorobutanamido]-2-(p-methylphenyl) benzoxazole were proved by elemental analysis. In the assay of the proteins by western, when heterocyclic compounds were added to the MDA and MCF-7 cell line, there was no difference from the control group in Apaf-1 and BCL-2 levels, but a reduction was observed in caspase and Nfkβ levels compared with the control group. It is seen that this newly synthesized heterocyclic compound increases apoptosis by reducing the activation of Nfkβ, and in this way has shown an effect of inhibiting tumor growth in cancer treatment.

A series of 2,5-disubstituted-benzoxazole derivatives (1–13) were evaluated as possible inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The results demonstrated that the compounds exhibited a broad spectrum of AChE and BChE inhibitory activity ranging between 6.80% and 90.21% except one compound which showed no activity against AChE at the specified molar concentration. Another derivative displayed a similar activity to that of reference drug (galanthamine) for inhibition of AChE and BChE. In addition, molecular docking of the compounds into active site of AChE was performed using recombinant human AChE (PDB ID: 4ey6) in order to understand ligand–protein interactions.