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    A chalcone showing positional disorder, two related diarylcyclohexenones showing enantiomeric disorder and a related hydroxyterphenyl, all derived from simple carbonyl precursors
    (Int Union Crystallography, 2015) Salian, Vinutha V.; Narayana, Badiadka; Yathirajan, Hemmige S.; Akkurt, Mehmet; Celik, Omer; Ersanli, Cem Cuneyt; Glidewell, Christopher
    Four compounds are reported, all of which lie along a versatile reaction pathway which leads from simple carbonyl compounds to terphenyls. (2E)-1-(2,4- Dichlorophenyl)-3-[4-(prop-1-en-2-yl)phenyl]prop-2-en-1-one, C18H14Cl2O, (I), prepared from 4-(prop-1-en-2-yl)benzaldehyde and 2,4-dichloroacetophenone, exhibits disorder over two sets of atomic sites having occupancies of 0.664 (6) and 0.336 (6). The related chalcone (2E)-3-(4-chlorophenyl)-1-(4-fluorophenyl)-prop-2-en-1-one reacts with acetone to produce (5RS)-3-(4-chlorophenyl)-5-[4-(propan-2-yl)phenyl]cyclohex-2-en-1-one, C21H21ClO, (II), which exhibits enantiomeric disorder with occupancies at the reference site of 0.662 (4) and 0.338 (4) for the (5R) and (5S) forms; the same chalcone reacts with methyl 3-oxobutanoate to give methyl (1RS, 6SR)-4-(4-chlorophenyl)-6-[4-(propan-2-yl)phenyl]-2-oxocyclohex-3-ene-1-carboxylate, C23H23ClO3, (III), where the reference site contains both (1R,6S) and (1S,6R) forms with occupancies of 0.923 (3) and 0.077 (3), respectively. Oxidation, using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, of ethyl (1RS, 6SR)-6-(4-bromophenyl)-4-(4-fluorophenyl)-2-oxocyclohex-3-ene-1-carboxylate, prepared in a similar manner to (II) and (III), produces ethyl 4 ''-bromo-4-fluoro-5'-hydroxy-1,1':3',1 ''-terphenyl-4'-carboxylate, C21H16BrFO3, (IV), which crystallizes with Z' = 2 in the space group P (1) over bar. There are no significant intermolecular interactions in the structures of compounds (I) and (II), but for the major disorder component of compound (III), the molecules are linked into sheets by a combination of C-H center dot center dot center dot O and C-H center dot center dot center dot pi(arene) hydrogen bonds. The two independent molecules of compound (IV) form two different centrosymmetric dimers, one built from inversion-related pairs of C-H center dot center dot center dot O hydrogen bonds and the other from inversion-related pairs of C-H center dot center dot center dot pi(arene) hydrogen bonds. Comparisons are made with related compounds.
  • Küçük Resim
    Öğe
    Crystal and Molecular Structure of N-Trityl-m-aminophenol Chloroform Solvate
    (Analytical Sciences, 2007) Çelik, İsmail; Ersanlı, Cem Cüneyt; Akkurt, Mehmet; Demirtaş, İ.
    The title compound, (C26H23N)3·CHCl3, was synthesized by the reaction of trityl bromide with m-toluidine in chloroform and crystalized in the trigonal R3 space group (Z = 6) with the one molecule of chloroform, and with a = 20.765(5), b = 20.765(5), c = 24.924(5)Å, ? = ? = 90°, ? = 120°, V = 9307(4)Å3, Z = 6 and Dx = 1.250 Mg m-3. A least-squares refinement gave a residual index of R = 0.065 for 3540 observed reflections. Three phenyl rings of the title compound are at angles of 60.39(13), 74.10(14) and 70.17(13)° to the six-membered ring of the planar aminophenol group. The dihedral angles between three phenyl rings are 73.60(16), 87.80(15) and 56.52(15)°.
  • Küçük Resim
    Öğe
    Crystal Structure of (1RS,2SR,3SR,4SR,9RS)-1,2,3,9-Tetrabromo-1,2,3,4-tetrahydro-1,4-methanonaphthalene
    (Analytical Sciences, 2007) Ersanlı, Cem Cüneyt; Akkurt, Mehmet; Daştan, Arif; Santiago, Garcia-Granda; Çelik, İsmail
    In the title compound, C11H8Br4, there is a norbornane skeleton with four Br atoms, having a benzene ring fused on one side. It crsytalizes in the orthorhombic Pbca space group. The unit-cell parameters at 294(2)K are a = 11.9910(10), b = 11.335(2), c = 18.191(4)Å, V = 2472.5(7)Å3, Dx = 2.470 g cm-3, Z = 8.
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    Crystal structure of 3,4a, 7,7,10a-pentamethyl-3-vinyldodecahydro-1H-benzo[f]chromen-9-ol isolated from Sideritis perfoliata
    (Int Union Crystallography, 2016) Celik, Ismail; Ersanli, Cem Cuneyt; Koseoglu, Rahmi; Aksit, Huseyin; Erenler, Ramazan; Demirtas, Ibrahim; Akkurt, Mehmet
    The asymmetric unit of the title compound, C20H34O2, contains two crystallographically independent molecules (1 and 2) with similar conformations. In both molecules, the cyclohexane rings adopt a chair conformation, while the oxane rings are also puckered. In the crystal, O-H center dot center dot center dot O hydrogen bonds connect adjacent molecules, forming C(6) helical chains located around a 21 screw axis and running along the crystallographic a axis. The packing of these chains is governed only by van der Waals interactions. Semi-empirical PM3 quantum chemical calculations are in a satisfactory agreement with the structural results of the X-ray structure analysis. The absolute structure was indeterminate in the present experiment.
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    Crystal structure of racemic [(1R,2S,3R,4S,6S)-2,6-bis(furan-2-yl)-4-hydroxy-4-(thiophen-2-yl)cyclohexane-1,3-diyl]bis(thiophen-2-ylmethanone)
    (Int Union Crystallography, 2016) Celik, Ismail; Ersanli, Cem Cuneyt; Akkurt, Mehmet; Gezegen, Hayrettin; Koseoglu, Rahmi
    In the title compound, C28H22O5S3, the central cyclohexane ring adopts a chair conformation. The atoms of the furan ring attached to the 6-position of the central cyclohexane ring are disordered over two sets of sites with occupancies of 0.832 (5) and 0.168 (5). The hydroxy group is disordered over two positions (at the 4- and 6-positions of the cyclohexane ring) in the ratio 0.832 (5): 0.168 (5). In the crystal, molecules are linked by C-H center dot center dot center dot O hydrogen bonds and C-H center dot center dot center dot pi interactions, forming layers parallel to (100).
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    Crystal structure of racemic [(1R,2S,3R,4S,6S)-2,6-bis(furan-2-yl)-4-hydroxy-4-(thiophen-2-yl)cyclohexane-1,3-diyl]bis(thiophen-2-ylmethanone) (vol E72, pg 976, 2016)
    (Int Union Crystallography, 2016) Celik, Ismail; Ersanli, Cem Cuneyt; Akkurt, Mehmet; Gezegen, Hayreddin; Koseoglu, Rahmi
    [No abstract available]
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    Dihydrooxazolones and dihydroimidazolones derived from acylglycines: syntheses, molecular structures and supramolecular assembly
    (Int Union Crystallography, 2015) Subbulakshmi, Karanth N.; Narayana, Badiadka; Yathirajan, Hemmige S.; Akkurt, Mehmet; Celik, Omer; Ersanli, Cem Cuneyt; Glidewell, Christopher
    Syntheses and structures are described for some alkylidene-substituted dihydrooxazolones and dihydroimidazoles derived from simple acylglycines. A second, triclinic, polymorph of 4-benzylidene-2-(4-methylphenyl)-1,3-oxazol-5(4H)-one, C17H13NO2, (I), has been identified and the structure of 2-methyl-4-[(thiophen-2-yl) methylidene]-1,3-oxazol-5(4H)-one, C9H7NO2S, (II), has been rerefined taking into account the orientational disorder of the thienyl group in each of the two independent molecules. The reactions of phenylhydrazine with 2-phenyl-4-[(thiophen-2-yl) methylidene]-1,3-oxazol-5(4H)-one or 2-(4-methylphenyl)-4-[(thiophen-2-yl) methylidene]-1,3-oxazol-5(4H)-one yield, respectively, 3-anilino-2-phenyl-5-[(thiophen-2-yl) methylidene]-3,5-dihydro-4H-imidazol-4-one, C10H15N3OS, (III), and 3-anilino-2-(4-methylphenyl)-5-[(thiophen-2-yl) methylidene]-3,5-dihydro-4H-imidazol-4-one, C21H17N3OS, (IV), which both exhibit orientational disorder in their thienyl groups. The reactions of 2-phenyl-4[(thiophen-2-yl) methylidene]-1,3-oxazol-5(4H)-one with hydrazine hydrate or with water yield, respectively, N-[3-hydrazinyl-3-oxo-1-(thiophen-2-yl) prop-1en-2-yl] benzamide and 2-(benzoylamino)-3-(thiophen-2-yl) prop-2-enoic acid, which in turn react, respectively, with thiophene-2-carbaldehyde to form 2-phenyl-5-[(thiophen-2-yl) methylidene]-3-{[(E)-(thiophen-2-yl) methylidene]amino}-3,5-dihydro-4H-imidazol-4-one, C19H13N3OS2, (V), which exhibits orientational disorder in only one of its thienyl groups, and with methanol to give methyl (2Z)-2-(benzoylamino)-3-(thiophen-2-yl) prop-2-enoate, C15H13NO3S, (VI). There are no direction-specific intermolecular interactions in the crystal structure of the triclinic polymorph of (I), but the molecules of (II) are linked by two independent C-H center dot center dot center dot O hydrogen bonds to form C-2(2)(14) chains. Compounds (III) and (IV) both form centrosymmetric R-2(2)(10) dimers built from N-H center dot center dot center dot O hydrogen bonds, while compound (V) forms a centrosymmetric R-2(2)(10) dimer built from C-H center dot center dot center dot O hydrogen bonds. In the structure of compound (VI), a combination of N-H center dot center dot center dot O and C-H center dot center dot center dot pi (arene) hydrogen bonds links the molecules into sheets. Comparisons are made with some similar compounds.
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    Molecular and crystal structure of 1-methyl- 5-trifluoromethoxy-1H-indole-2,3-dione 3-[4-(4-methoxyphenyl)thiosemicarbazone]
    (Istanbul Üniversitesi, 2021) Eter, Özge Soylu; Atioglu, Zeliha; Akkurt, Mehmet; Ersanli, Cem Cüneyt; Karali, Nilgün
    Background and Aims: The main purpose of this study is to determine the molecular structure and isomers of the new 1-methyl- 5-trifluoromethoxy-1H-indole-2,3-dione 3-
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    Öğe
    Molecular and crystal structure of 1-methyl-5-trifluoromethoxy-1H-indole-2,3-dione 3-[4-(4-methoxyphenyl)thiosemicarbazone]
    (Istanbul Univ, Fac Pharmacy, 2021) Eter, Ozge Soylu; Atioglu, Zeliha; Akkurt, Mehmet; Ersanli, Cem Cuneyt; Karali, Nilgun
    Background and Aims: The main purpose of this study is to determine the molecular structure and isomers of the new 1-methyl-5-trifluoromethoxy-1H-indole-2,3-dione 3-[4-(4-methoxyphenyl)thiosemicarbazone] (5) and to prove the 3Z-conformer of the compound 5. Methods: The molecular structure of E- and Z-isomer mixture 5 was confirmed by analytical and spectral data (UV, IR, H-1 NMR, HSQC-2D and MS). The Z-conformer of compound 5 was characterized by NMR spectroscopy and X-ray single crystal diffraction analysis method (SC-XRD). Results: The compound 5 was synthesized by condensation of 1-methyl-5-trifluoromethoxy-1H-indole-2,3-dione (2) with 4-(4-methoxyphenyl)thiosemicarbazide (4). The compound 5 was obtained in two separate forms, crystal and amorphous. It was proved by NMR data and X-ray diffraction findings that the crystal form is the Z-isomer and the amorphous form is a mixture of the E- and Z-isomers. The E- and Z-isomer ratios were determined by H-1 NMR spectroscopy. The crystal structure and molecular interactions of the Z-conformer were determined by X-ray single crystal diffraction analysis. Conclusion: In the crystal, three intramolecular N-H center dot center dot center dot N, N-H center dot center dot center dot O and C-H center dot center dot center dot S hydrogen bonds provided isomer formation. Also, molecular packing was stabilized by intermolecular C-H center dot center dot center dot O hydrogen bonds, the pi-pi stacking interactions and weak CO center dot center dot center dot pi (ring) contacts.
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    Synthesis of some novel indeno[1,2-b]quinoxalin spiro-β-lactam conjugates
    (Pergamon-Elsevier Science Ltd, 2017) Rad, Javad Ameri; Jarrahpour, Aliasghar; Ersanli, Cem Cuneyt; Atioglu, Zeliha; Akkurt, Mehmet; Turos, Edward
    This article reports the synthesis of some new spiro-beta-lactams bearing an indeno[1,2-b]quinoxaline ring system, prepared by a [2 + 2] cycloaddition of ketenes with imines derived from 11-H-indeno[1,2-b] quinoxalin-11-one. The structures of newly synthesized spiro-beta-lactams 2a-i and 3a-i were characterized by FT-IR, H-1 NMR, C-13 NMR, mass spectrometry and elemental analyses. The relative stereochemistry of spiro-beta-lactams 2a and 3a was determined unequivocally by X-ray crystallographic studies. (C) 2017 Elsevier Ltd. All rights reserved.
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    Synthesis, Crystal Structure and Theoretical Characterization of (3R, 4R, 6S)-3,6-Dihydroxy-1-Menthene Isolated from Echinophora Tenuifolia
    (Gazi Univ, 2016) Celik, Ismail; Ersanli, Cem Cuneyt; Akkurt, Mehmet; Aksit, Huseyin; Erenler, Ramazan
    In the title compound, C10H18O2, the cyclohexene ring adopts a half-chair conformation. In the crystal strcuture, weak inter(sic)molecular O-H center dot center dot center dot O hydrogen bonds connect the adjacent molecules, forming edge-fused R23(8) ring motifs, into the hollow columns parallel to the b-axis direction. The crystal packing is governed only by van der Waals inter(sic)actions. There is no further C-H center dot center dot center dot pi and pi-pi interactions. The H atom in one of two hydroxyl groups was found to be disordered over two sites. The occupancy factors of the two sites were refined to 0.52 (2) and 0.48 (2). Semi-empirical PM3 quantum chemical calculations are in satisfactory agreement with the results of the X-ray structure analysis.
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    The crystal structures of three 3-methyl-1H-1,2,4triazole-5-thiones, including a second polymorph of 4-[(E)-(5-bromo-2-hydroxybenzylidene)amino]-3methyl-1H-1,2,4-triazole-5(4H)-thione and a redetermination of 4-amino-3-methyl-1H-1,2,4-triazole-5(4H)-thione
    (Int Union Crystallography, 2015) Manjula, Padmanabha S.; Sarojini, Balladka K.; Yathirajan, Hemmige S.; Akkurt, Mehmet; Ersanli, Cem Cuneyt; Glidewell, Christopher
    The structures of three 3-methyl-1H-1,2,4-triazole-5-thione derivatives are reported. The structure of 4-amino-3-methyl-1H-1,2,4-triazole-5(4H)-thione, C3H6N4S, (I), has been redetermined with an improved model for the H atoms: the non-H atoms of (I) all lie on mirror planes in space group Pbcm, and the H atoms of the methyl group are disordered over two sets of reflection-related atomic sites having occupancy 0.5: two independent N-H center dot center dot center dot S hydrogen bonds link the molecules of compound (I) into complex sheets. The non-H atoms in the molecules of 4-[(E)-(3,4-dimethoxybenzylidene) amino]-3-methyl-1H-1,2,4-triazole- 5(4H)-thione, C12H14N4O2S, (II), despite lying in general positions are close to planar, with a dihedral angle between the two rings of 6.31 (10) degrees : the molecules of compound (II) are linked by a three-centre N-H center dot center dot center dot (O)2 hydrogen bond into a C(10) C(11)[ R12 (5)] chain of rings. A second polymorph of 4-[(E)-(5bromo- 2-hydroxy-5-bromobenzylidene) amino]-3-methyl-1H-1,2,4-triazole-5(4H)thione, C10H9BrN4OS, (III), has been identified; the non-H atoms are nearly coplanar with a dihedral angle between the two rings of 1.9 (4) degrees. There is an intramolecular O-H center dot center dot center dot N hydrogen bond and the molecules are linked by NH center dot center dot center dot S hydrogen bonds, forming centrosymmetric R-2(2) (8) dimers. Comparisons are made with some related structures.