No abstract

3‐(4‐Chlorophenyl)‐3a,4,8,8a‐tetrahydro‐[1,3,2]dioxaborepino[5,6‐d] isoxazoles were synthesized from the reaction of (3‐(4‐chlorophenyl)‐4,5‐dihydroisoxazole‐4,5‐diyl)dimethanol with substituted phenylboronic acids. Crystal structure of 1‐(4‐(3‐(4‐chlorophenyl)‐3a,4,8,8a‐tetrahydro‐[1,3,2]dioxaborepino[5,6‐d]isoxazol‐6‐yl)phenyl) ethanone was studied and the values of selected bond distances (Å), bond angles (°), and dihedral angles (°) were found in agreement with the calculated (DFT, B3LYP/6‐311++G(d,p)) values. Antimicrobial activity of these new compounds was also studied against a panel of microorganisms including Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, Streptococcus mutans, and Candida albicans. Most of the dioxaborepines exhibited fair activities against these microorganisms. The pMIC values of the compounds were first correlated with Hammett polar substituent constant (σ) together with lipophilic constant (π) and statistically significant 2D correlations were obtained. In addition, the pMIC values of the compounds were correlated with some theoretical descriptors and fair 2D‐QSAR models with clogP, SAA, and μ as independent variables were obtained.

ÖzBu çalışmanın amacı, bazı dioksaborepin bileşiklerini (2a-c) sentezlemek ve (2a) bileşiği için çeşitli mikroorganizmalara karşı antimikrobiyal aktivite sonuçlarını değerlendirmektir. Mikrodilüsyon yöntemi için Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25923), Echerichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Streptococcus mutans (ATCC 25175) ve Candida albicans (ATCC 90028) kullanılmıştır. Dioksaborepin bileşiği (2a) özellikle hastane enfeksiyonuna neden olabilen P. aeruginosa'ya karşı iyi sonuç vermiştir. Dioksaborepin bileşiği (2a) Gram negatif ve Gram pozitif bakteriler ve mantara karşı aktivite göstermiştir. Bu çalışmadaki sonuçlara göre günümüzde, bor içeren yeni bileşiklerin sentezi ve aktivite testleri önemli bir yer tutmaktadır. Bu tür bileşikler geliştirilebilir ve gelecekte daha etkili, yeni antibakteriyel ve antifungal madde tasarımında kullanılabilirler.

No abstract

Substituent effects on 1 H and 13 C NMR chemical shifts of 5-substituted phenyl-3-phenyl-4,5-dihydro-1,2,4,5-oxadiazaboroles (1a-r) were studied respectively. Single and duel substituent parameters were used for the correlation analysis of substituent-induced chemical shifts with σ, F and R constants. The calculations have shown the polar and resonance substituent effects on N-H proton and C=N carbon atoms. The ρ value was found positive for compounds (1a-r), which means that the substituent effect is normal. Additionally, crystal structure of compound (1i) was also studied. Density functional theory (DFT) calculations were carried out to calculate the theoretical chemical shifts, bond distances and bond angles.

We intended to quantify the antibacterial and antifungal activity results of 4,5-dihydroisoxazole dimethanol compound (1a) against several bacteria and fungi and also calculate some structural parameters (theoretical descriptors) of compound (1a) with this work. Microdilution broth procedures were studied using microdilution wells for the minimal inhibitory concentrations (MICs) test. Compound (1a) exhibited fair activities against all the bacteria and fungi. Compound (1a) has been a good result (MIC = 50 µg/ml) against particularly P. aeruginosa. The structure of compound (1a) was drawn, and geometrical optimization was done using the Ab initio (RHF/3-21G) level.

No abstract

Bu çalışmanın amacı, bazı oksadiazol hetero halkalı bileşiklerin (1a-g) çeşitli bakterilere karşı antimikrobiyal aktivite sonuçlarının değerlendirilmesidir. Elde edilen MİK değerleri ve hesaplanan çeşitli parametreler kullanılarak yapı aktivite ilişkileri değerlendirilip biyolojik aktiviteye sübstitüentin etkisi belirlenmiştir.