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121.
Ismail Özdemir Nevin Gürbüz Yetkin Gök Bekir Çetinkaya Engin Çetinkaya 《Transition Metal Chemistry》2005,30(3):367-371
Six rhodium–carbene complexes (2a–f) have been prepared and the new compounds characterized by C, H, N analyses, 1H-n.m.r. and 13C-n.m.r. Phenylboronic acid reacts with aldehydes in the presence of a catalytic amount of rhodium(I)–carbene complex, RhCl(COD)(1,3-dialkylbenzimidazolidin-2-ylidene), (2a–f), to give the corresponding aryl secondary alcohols in good yields. 相似文献
122.
Osman Dayan Muharrem Diner Bekir etinkaya Namk
zdemir 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):m315-m318
In the title compound, [CuCl2(C11H15N3O2)], the CuII ion is five‐coordinated in a strongly distorted trigonal–bipyramidal arrangement, with the two methyloxime N atoms located in the apical positions, and the pyridine N and the Cl atoms located in the basal plane. The two axial Cu—N distances are almost equal (mean 2.098 Å) and are substantially longer than the equatorial Cu—N bond [1.9757 (15) Å]. It is observed that the N(oxime)—M—N(pyridine) bond angle for five‐membered chelate rings of 2,6‐diacetylpyridine dioxime complexes is inversely related to the magnitude of the M—N(pyridine) bond. The structure is stabilized by intra‐ and intermolecular C—H⋯Cl hydrogen bonds which involve the methyl H atoms, except for one of the two acetylmethyl groups. 相似文献
123.
Merve Yuzbasioglu Baran Zuhal Guvenalp Iclal Saracoglu Cavit Kazaz Bekir Salih L. Omur Demirezer 《Natural product research》2020,34(12):1669-1677
AbstractIn this study, phytochemical composition of Arnebia densiflora (AD) was determined and cytotoxic effects of the n-hexane extract and compounds isolated from this species on various cell lines were investigated. By means of serial chromatographic studies, 6 naphthoquinone derivatives were yielded, which are isovalerylalkannin, α-methyl-n-butyl alkannin, acetylalkannin, β-acetoxy isovalerylalkannin, alkannin and a new compound: 4-hydroxy 4-methyl valeryl alkannin. Structures of the isolated compounds were elucidated using UV, IR, 1D-2D NMR, MS and CD methods. Cytotoxic effects of the extract and isolated alkannins were investigated on L929, HeLa, HEp-2 cells. AD and the isolated compounds demonstrated moderate to strong cytotoxic effects (IC50 range: 4.92-172.35?µg/ml). The results of DNA fragmentation and caspase-3 activity studies on HeLa cells exhibited that AD and the naphthoquinones isolated from it caused cytotoxicity through induction of apoptosis. 相似文献
124.
125.
Mevlüde Canlca Ahmet Altndal Ali Rza
zkaya Bekir Salih
zer Bekarolu 《Polyhedron》2008,27(7):1883-1890
4,4′-Isopropylidendioxydiphenyl bridged bis-metallophthalocyanines Zn(II) (5) and Co(II) (6) were synthesized from the compound 4,4′-isopropylidendioxydiphthalonitrile (3) and 4,5-bis(hexylthio)phthalonitrile (4). The new cofacial bis-phthalocyanines Zn(II) (7) and Co(II) (8) were synthesized from the corresponding 3 which can be obtained by the reaction of 4,4′-isopropylidendiphenol (1) with 4-nitrophthalonitrile (2). These complexes have been characterized by elemental analysis, UV/Vis, FT-IR, 1H NMR and MALDI-TOF mass spectroscopies. The electrochemical properties of the complexes were examined by cyclic voltammetry, differential pulse voltammetry and controlled potential coulometry in nonaqueous media. Electrochemical results showed that while there is not any considerable interaction between the two phthalocyanine rings in bisphthalocyanine complexes 5 and 6, the splitting of the molecular orbitals occurs as a result of the strong interaction between the phthalocyanine rings in cofacial complexes 7 and 8.
Measurements of capacitance showed a well defined decrease with increasing frequency and an increase with increasing temperature at lower frequencies. 相似文献
126.
Aytaç Gürhan Gökçe Hayati Türkmen Muhittin Aygün Bekir Çetinkaya Orhan Büyükgüngör 《Structural chemistry》2008,19(1):57-62
Trans-Bis[1,3-bis(2,4-dimethylphenylimidazolidin-2-ylidene)]dichloropalladium(II), 4, was prepared from 1,3-bis(2,4-dimetilphenyl)imidazoliniumchloride. The crystal and molecular structure of 4 have been determined by single crystal X-ray diffraction. The title compound, C38H44N4PdCl2, crystalizes in the monoclinic space group P 21/n with a = 13.8713(9) Å, b = 12.1365(6) Å, c = 21.5499(15) Å. The Pd atom has a slightly distorted square planar coordination geometry. The molecules of the title compound are linked by C–H···Cl weak hydrogen bonds into two-dimensional sheets parallel to the (001) plane. In addition, the title compound was characterized by elemental analyses and NMR spectroscopy. 相似文献
127.
Selective O-benzylation of primary hydroxy compounds has been achieved in the presence of bis[acetylacetonato]copper with benzyl chloride. We showed that bis[acetylacetonato]copper was very efficient in promoting the benzylation of primary aliphatic alcohols versus secondary aliphatic alcohols and phenolic hydroxy groups selectively. 相似文献
128.
Yahya Nural Rafet Kilincarslan H. Ali Dondas Bekir Cetinkaya Mehmet Sami Serin Ronald Grigg Tuncay Ince Colin Kilner 《Polyhedron》2009,28(14):2847-2854
A series of Ni(II), Pd(II) and Cu(II) metal complexes of highly functionalized aroylaminocarbo-N-thioyl pyrrolidines were prepared and characterized by microanalysis, spectroscopic methods, magnetic susceptibility measurements and single crystal X-ray diffraction studies. The antifungal activity of the metal complexes against the yeast Saccharomyces cerevisae and against the fungus Penicillium digitatum was studied. 相似文献
129.
Kouroush Salimi idem Kip
mür elikbak Duygu Deniz Usta Asl Pnar Bekir Salih Ali Tuncel 《Biomedical chromatography : BMC》2019,33(6)
In this study, poly(vinylphosphonic acid‐co‐ethylene dimethacrylate), poly(VPA‐co‐EDMA) capillary monolith was synthesized as a starting material for obtaining a stationary phase for microscale enrichment of phosphopeptides. The chelation of active phosphonate groups with Ti (IV) ions gave a macroporous monolithic column with a mean pore size of 5.4 μm. The phosphopeptides from different sources were enriched on Ti (IV)‐attached poly(VPA‐co‐EDMA) monolith using a syringe‐pump. The monolithic capillary columns exhibited highly sensitive/selective enrichment performance with phosphoprotein concentrations as low as 1.0 fmol/mL. Six different phosphopeptides were detected with high intensity by the treatment of β‐casein digest with the concentration of 1.0 fmol/mL, using Ti (IV)@poly(VPA‐co‐EDMA) monolith. Highly selective enrichment of phosphopeptides was also successfully carried out even at trace amounts, in a complex mixture of digested proteins (molar ratio of β‐casein to bovine serum albumin, 1:1500) and three phosphopeptides were successfully detected. Four highly intense signals of phosphopeptides in human serum were also observed with high signal‐to‐noise ratio and a clear background after enrichment with Ti (IV)@poly(VPA‐co‐EDMA) monolith. It was concluded that the capillary microextraction system enabled fast, efficient and robust enrichment of phosphopeptides from microscale complex samples. The whole enrichment process was completed within 20 min, which was shorter than in the previously reported studies. 相似文献
130.
Aye Kuruüzüm‐Uz Zuhal Güvenalp Cavit Kazaz Bekir Salih L.
mür Demirezer 《Helvetica chimica acta》2010,93(3):457-465
Four new triterpene glycosides, named oleanazuroside 1 ( 1 ), oleanazuroside 2 ( 2 ), ursolazuroside 1 ( 3 ), and ursolazuroside 2 ( 4 ), together with the seven known compounds 5 – 11 , were isolated from the MeOH extract of the aerial parts of Anchusa azurea Miller var. azurea. Their structures were elucidated by means of spectroscopic evidence (UV, IR, MALDI‐MS, and 1D‐ and 2D‐NMR). The radical‐scavenging activities against 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) of the BuOH extract and of 8 and 10 were very strong (Table 5). 相似文献