Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Synthesis and Antifungal and Antibacterial Bioactivities of Diborolanes Containing Arylamines
    (Elsevier, 2023) Aygün, Muhittin; Sevinçek, Resul; Özgener, Hüseyin; Bıyık, Hacı Halil; Metin, Kubilay; Şahin, Yüksel; Poyrazoğlu Çoban, Esra; Gürbüz, Burçin
    A good yield of 1,2-diarylamino-1,2-diborolanes 2 was obtained from the reaction of 1,2-dichloro-1,2-diborolane 1 and ArNHLi (an anilide). The structures of these new derivatives were characterized by nuclear magnetic resonance spectroscopy. The molecular structures of 2a and 2b were also determined using single-crystal X-ray diffraction. Antimicrobial activities of synthesized compounds against some Gram-positive and -negative bacteria and yeasts were determined. Some compounds were found to have strong antibacterial and antifungal properties, especially against the bacterium, S. pneumonia, which is the causative agent of pneumonia, and the fungus, C. albicans, which is the causative agent of candidiasis. The compounds 2a and 3 had a powerful effect (compound 2a and 3 = 1 μgmL−1) against S. pneumoniae ATCC 27336 bacteria. In addition, compounds 2a, 3 and 2f were observed to have strong effects (compound 2a, 3, 2f = 2 μgmL−1) against C. albicans ATCC 10231 and C. utilis ATCC 9950. The results obtained were found to be more effective than the MIC values (128–64 μgmL−1) of Streptomycin and Flukanozol drugs used for bacteria and yeasts. The results of our study show that the synthesized substances can be used for new drug applications that are being developed against infectious diseases in the pharmaceutical industry. © 2023 Elsevier B.V.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 5
    Cytotoxic and Apoptotic Effects of 1,2-Diborolanes With Strong Donor Substitutes on Human Cancer Cells
    (Elsevier, 2021) Şahin, Yüksel; Aslantürk, Özlem Sultan; Çelik, Tülay; Sevinçek, Resul; Aygün, Muhittin; Metin, Kubilay; Fırıncı, Erkan; Özgener, Hüseyin
    In recent years, boron compounds have become more common as chemotherapy agents against certain types of cancers. Along with the development of boron-based therapeutic agents have come investigations into the various cancers and biochemical and molecular mechanisms affected by boron compounds and the relationships between boron compounds and chemical protection against cancer. In this preliminary study, the effects of new 1,2-N-substituted-1,2-diborolane derivatives on types of breast and liver cancers were examined for the first time. Four were found to significantly affect the cell viabilities and mitochondrial membrane potential changes in MCF-7, HepG2 and Hep3B cancer cells. Each was prepared in n-hexane at various concentrations (5, 10, 25, 50, 75 and 100 µg/mL). Human peripheral blood lymphocytes were used as control cells. Compounds 1, 2, 3a, and 3b 1,2-diborolane derivatives selectively killed cancer cells, but compound 1 was cytotoxic in a concentration-dependent manner on HepG2 and Hep3B and only at concentrations of at least 75 µg/mL on MCF-7 cells. Compound 3a exhibited cytotoxic effect on lymphocytes at 75 and 100 µgmL-1 concentrations, but compounds 1, 2 and 3b, 3c and 3d have not possessed significant cytotoxic effect on lymphocytes. Compounds 3c and 3d have not possessed significant cytotoxic effects. Mitochondrial membrane potential assay results supported these findings. Our results reveal that 1,2-diborolane derivates have high cytotoxic and apoptotic activities on human hepatocarcinoma cells and are therefore potential candidates in the development of new drugs against liver cancer.
  • Article
    Citation - WoS: 8
    Citation - Scopus: 9
    1,2-Diborolanes With Strong Donor Substituents: Synthesis and High Antimicrobial Activity
    (Academic Press, 2021) Şahin, Yüksel; Poyrazoğlu Çoban, Esin; Sevinçek, Resul; Bıyık, Halil H.; Özgener, Hüseyin; Aygün, Muhittin
    1,2-diborolanes with strong and without strong donor substituents have been described, and are also referred to as 1,2-diboracyclopentane. The 1,2-diaryl/alkyl-amino-1,2-diboracyclopentanes 2, 3, and 4 were obtained in good yield after the reaction of 1,2-dichloro-1,2-diboracyclopentane 1 with ArNHLi and Me3Si-NR2. The structures of these new derivatives were characterized by nuclear magnetic resonance spectroscopy. The molecular structures of 2b, 2c, 2e, 4, and 5f were also determined by single-crystal X-ray diffraction. The newly synthesized 1,2-borolanes are stable in air and showed particularly high activity against some Gram-positive bacteria. © 2020 Elsevier Inc.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Synthesis and Structures of 1,3,2,4,5-Diazatriborolidines
    (Elsevier, 2019) Fırıncı, Erkan; Sevinçek, Resul; Bursalı, Banu; Özgener, Hüseyin; Burgaz, Osman; Şen, Ceren; Şahin, Yüksel
    The derivatives of diazatriborolidine are a class of 5-membered heterocyclic compounds containing a ring with two nitrogen atoms and three boron atoms. The 1,3,2,4,5-diazatriborolidine derivatives were synthesized from 1,2-bis(N-lithium-arylamino) diborane(4) and dichloro-dimethylaminoborane with high yield. The structures of these new derivatives were determined using nuclear magnetic resonance (NMR) spectroscopy. The molecular structures of 3a, 3b, 3d, 4b and 4c were determined using single-crystal X-ray diffraction. Their structural features were discussed and compared with similar diazatriborolidines. In addition, the enthalpy of formation of B and N atoms containing five membered heterocycles were calculated theoretically for the first time. Also, an easy and efficient synthesis route has been reported for preparation of 1,3,2,4,5-diazatriborolidine derivatives.
  • Article
    Citation - WoS: 46
    Citation - Scopus: 50
    Investigation of Europium Concentration Dependence on the Luminescent Properties of Borogermanate Glasses
    (Elsevier Ltd., 2017) Gökçe, Melis; Şentürk, Ufuk; Uslu, Deniz K.; Burgaz, Gözde; Şahin, Yüksel; Gökçe, Aytaç Gürhan
    In order to elucidate the effect of europium content on the optical and luminescent properties of borogermanate glasses, a series of Eu3+ doped 30B2O3-40GeO2-(30-x)Gd2O3 glasses with various doping levels (x=1–9 mol%) have been synthesized and studied with transmission, absorption, photoluminescence and decay time measurements. The transmission spectra proved that the title glasses maintained a high transparency about 80% in the 440 to 900 nm region. Based on the absorption spectra, the optical band gaps obtained from Tauc's plot can be narrowed by increasing content of Eu3+. From the photoluminescence spectra, the strongest red emission has been observed from the 5D0→7F2 level of Eu3+ ions in borogermanate glasses. The strongest emission and excitation intensities of Eu3+ ions are at the doping level of x=7 mol% and then these intensities decrease due to concentration quenching. The red to orange ratio (R/O) of 5D0→7F2 to 5D0→7F1 transitions has been investigated to predict the local environment of Eu3+ ions. Judd-Ofelt (J-O) analyses have been performed from the emission spectra. The values of R/O and Ω2 present an increase with increasing doping level, indicating the lower symmetric environment for Eu3+ ions and higher covalency for Eu-O bond. The emission efficiency calculated from J-O theory is 75% at x=2 mol%. The decay time curves of 6P7/2→8S7/2 transition of Gd3+ ions and 5D0–7F2 transition of Eu3+ ions confirm the energy transfer from Gd3+ to Eu3+ ions.