William T. A. Harrison

The American University in Cairo, Cairo, Muhafazat al Qahirah, Egypt

Are you William T. A. Harrison?

Claim your profile

Publications (573)447.92 Total impact

  • Source
    Ola K Sakka, Daisy H Fleita, William T A Harrison
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, CHNOS, the essentially planar thia-zole ring (r.m.s. deviation = 0.022 Å) forms dihedral angles of 84.88 (9) and 1.8 (3)° with the phenyl ring and the -C(CN) group (r.m.s. deviation = 0.003 Å), respectively. The mol-ecule has approximate local symmetry. In the crystal, molecules are linked C-H⋯N hydrogen bonds, forming chains propagating along [101]. The crystal studied was found to be an inversion twin with a refined 0.63 (1):0.37 (1) domain ratio.
    Acta Crystallographica Section E Structure Reports Online 03/2013; 69(Pt 3):o350. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, CHClNOS, the dihedral angle between the aromatic rings is 6.62 (2)° and the C=N-N=C torsion angle is 176.2 (4)°. The thia-zine ring shows an envelope conformation, with the S atom displaced by 0.633 (6) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.037 Å). The Cl atom is an an axial conformation and is displaced by 2.015 (6) Å from the thia-zine ring plane. In the crystal, mol-ecules are linked by C-H⋯O inter-actions, generating a three-dimensional network. Very weak aromatic π-π stacking inter-actions [centroid-centroid separations = 3.928 (2) Å] are also observed.
    Acta Crystallographica Section E Structure Reports Online 03/2013; 69(Pt 3):o422-3. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(17)H(16)BrN(3)O(2)S, the dihedral angle between the aromatic rings is 1.24 (15)° and the C=N-N=C torsion angle is 167.7 (3)°. The conformation of the thia-zine ring is an envelope, with the S atom displaced by 0.805 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.027 Å). In the crystal, C-H⋯O inter-actions link the mol-ecules into C(10) [010] chains. A weak C-H⋯π inter-action is also observed.
    Acta Crystallographica Section E Structure Reports Online 02/2013; 69(Pt 2):o164. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(18)H(16)ClN(3)O(2)S, the dihedral angle between the aromatic rings is 4.81 (2)° and the alkyl chain takes on an extended conformation [N-C-C-C = 179.2 (4)°]. The conformation of the thia-zine ring is an envelope, with the S atom displaced by -0.805 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.046 Å). The Cl atom is an axial conformation and is displaced by 1.761 (4) Å from the thia-zine ring plane. In the crystal, inversion dimers linked by pairs of C-H⋯O inter-actions generate R(2) (2)(20) loops and further C-H⋯O hydrogen bonds link the dimers into (001) sheets. Weak aromatic π-π stacking inter-actions [centroid-centroid separations = 3.870 (3) and 3.883 (3) Å] are also observed.
    Acta Crystallographica Section E Structure Reports Online 02/2013; 69(Pt 2):o165. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(19)H(21)N(3)O(2)S, the dihedral angle between the aromatic rings is 6.7 (2)° and the C=N-N=C torsion angle is 178.0 (2)°. The conformation of the thia-zine ring is an envelope, with the S atom displaced by 0.802 (2) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.022 Å). In the crystal, mol-ecules are linked by C-H⋯O inter-actions, generating C(5) chains propagating in [010]. A weak C-H⋯π inter-action is also observed.
    Acta Crystallographica Section E Structure Reports Online 02/2013; 69(Pt 2):o200. · 0.35 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Four trans-palladium(II)- and trans-platinum(II)-chlorido complexes, trans-[PdCl(2)(2-hmpy)(2)] (1), trans-[PtCl(2)(2-hmpy)(2)] (2), trans-[PdCl(2)(2-hepy)(2)] (3) and trans-[PtCl(2)(2-hepy)(2)] (4) (2-hmpy = 2-(hydroxymethyl)pyridine and 2-hepy = 2-(2-hydroxyethyl)pyridine), have been synthesized and characterized by elemental analysis, IR, NMR, and X-ray diffraction. The binding properties of these complexes with fish sperm DNA (FS-DNA) were investigated by UV titration, viscosity, thermal denaturation and electrophoresis measurements. The complexes can bind to FS-DNA and complex 4 exhibits the highest binding constant. Gel electrophoresis assay demonstrates that all the complexes can cleave the pCMV-βgal plasmid DNA to a different degree. The cytotoxic activities of the complexes were tested against four different cancer cell lines. In general, the platinum(II) complexes are more effective than the isostructural palladium(II) complexes. Complex 4 shows high anticancer activity, compared to transplatin, cisplatin, carboplatin and oxaliplatin.
    European journal of medicinal chemistry 12/2012; 60C:386-394. · 3.27 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(16)H(13)BrFN(3)O(2)S, the dihedral angle between the aromatic rings is 2.55 (19)° and the C=N-N=C torsion angle is 178.9 (3)°. The conformation of the thia-zine ring is an envelope, with the S atom displaced by -0.811 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.042 Å). In the crystal, C-H⋯O inter-actions link the mol-ecules and weak aromatic π-π stacking between the fluoro-benzene and bromo-benzene rings [centroid-centroid separation = 3.720 (2) Å and inter-planar angle = 2.6 (2)°] is also observed.
    Acta Crystallographica Section E Structure Reports Online 10/2012; 68(Pt 10):o2851. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(22)H(23)NO(4)S(2), the dihedral angles between the dimethyl-phenyl ring and the two methyl-phenyl rings are 41.19 (15) and 20.50 (17)°; the dihedral angle between the methyl-phenyl rings is 48.11 (14)°. The C-N-S-C torsion angles are -87.6 (2) and 77.43 (18)°. The only possible directional inter-actions in the crystal are very weak C-H⋯π inter-actions and very weak π-π stacking between parallel methyl-phenyl rings [centroid-to-centroid separation = 4.010 (2) Å and slippage = 1.987 Å].
    Acta Crystallographica Section E Structure Reports Online 10/2012; 68(Pt 10):o3013. · 0.35 Impact Factor
  • Source
    Muhammad Shafiq, William T A Harrison, Islam Ullah Khan, Ejaz
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(17)H(17)N(3)O(2)S, the dihedral angle between the aromatic rings is 6.3 (5)° and the C=N-N=C group is statistically planar [torsion angle = 179.8 (8)°]. The conformation of the thia-zine ring is an envelope, with the S atom displaced by 0.823 (9) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.012 Å). In the crystal, C-H⋯O inter-actions link the mol-ecules into C(5) chains propagating along [101]. The chains are consolidated by weak aromatic π-π stacking between the benzene and toluene rings [centroid-to-centroid separation = 3.826 (5) Å and inter-planar angle = 6.3 (4)°].
    Acta Crystallographica Section E Structure Reports Online 10/2012; 68(Pt 10):o2971. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(20)H(17)F(2)NO(4)S(2), the dihedral angles between the o-xylene ring and the fluoro-benzene rings are 31.7 (1) and 32.8 (1)°, and the dihedral angle between the fluoro-benzene rings is 50.9 (1)°. The C-N-S-C torsion angles are 76.7 (2) and 101.8 (2)°. In the crystal, mol-ecules are connected by C-H⋯O inter-actions into sheets in the ab plane.
    Acta Crystallographica Section E Structure Reports Online 10/2012; 68(Pt 10):o2973. · 0.35 Impact Factor
  • Source
    Muhammad Shafiq, William T A Harrison, Islam Ullah Khan
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(16)H(13)BrN(4)O(4)S, the dihedral angle between the aromatic rings is 4.1 (2)° and the C=N-N=C torsion angle is 175.5 (3)°. The nitro group is almost coplanar with the benzene ring to which it is attached [dihedral angle = 2.9 (7)°]. The thia-zine ring has an S-envelope conformation with the S atom displaced by 0.819 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.017 Å). In the crystal, C-H⋯O inter-actions link the mol-ecules and weak aromatic π-π stacking [centroid-centroid separation = 3.874 (2) Å] is also observed.
    Acta Crystallographica Section E Structure Reports Online 09/2012; 68(Pt 9):o2717. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(16)H(15)N(3)O(3)S, the dihedral angle between the aromatic rings is 8.18 (11)° and the C=N-N=C torsion angle is 178.59 (14)°. The conformation of the thia-zine ring is an envelope, with the S atom displaced by 0.8157 (18) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.045 Å). An intra-molecular O-H⋯N hydrogen bond closes an S(6) ring. In the crystal, weak C-H⋯O inter-actions link the mol-ecules, with all three O atoms acting as acceptors.
    Acta Crystallographica Section E Structure Reports Online 09/2012; 68(Pt 9):o2643. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(14)H(13)Cl(2)NO(2)S, the dihedral angle between the aromatic rings is 62.21 (7)° and the C-S-N-C group adopts a gauche conformation [torsion angle = 60.22 (17)°]. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(4) chains propagating in [010]. A short inter-molecular Cl⋯O contact of 3.1115 (17) Å is seen.
    Acta Crystallographica Section E Structure Reports Online 09/2012; 68(Pt 9):o2748. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(14)H(12)FNO(4)S, the dihedral angle between the aromatic rings is 50.26 (9)° and the C-S-N-C bond adopts a gauche conformation [torsion angle = -68.12 (15)°]. The dihydro-dioxine ring is disordered over two orientations, which both approximate to half-chairs, in a 0.880 (7):0.120 (7) ratio. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(4) chains propagating in [100]. Weak C-H⋯O and C-H⋯F inter-actions consolidate the packing.
    Acta Crystallographica Section E Structure Reports Online 08/2012; 68(Pt 8):o2433. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(13)H(11)Cl(2)NO(2)S, the dihedral angle between the aromatic rings is 76.62 (10)° and the C-S-N-C linkage between the rings adopts a gauche conformation [torsion angle = -51.4 (2)°]. A weak intra-molecular C-H⋯O inter-action closes an S(6) ring. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R(2) (2)(8) loops.
    Acta Crystallographica Section E Structure Reports Online 08/2012; 68(Pt 8):o2476. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(17)H(15)N(3)O(6)S, which crystallized with highly disordered methanol and/or water solvent mol-ecules, the dihedral angle between the the indole and benzene ring systems is 5.3 (2)°, which allows for the formation of intra-molecular π-π stacking inter-actions [centroid-centroid separations = 3.641 (3) and 3.694 (3) Å] and an approximate overall U-shape for the mol-ecule. In the crystal, dimers linked by pairs of N(s)-H⋯O(c) (s = sulfonamide and c = carboxyl-ate) hydrogen bonds generate R(2) (2)(10) loops, whereas N(i)-H⋯π (i = indole) inter-actions lead to chains propagating in [100] or [010]. Together, these lead to a three-dimensional network in which the solvent voids are present as inter-secting (two-dimensional) systems of [100] and [010] channels. The title compound was found to contain a heavily disordered solvent mol-ecule, which could be methanol or water or a mixture of the two. Due to its uncertain nature and the unresolvable disorder, the data were processed with the SQUEEZE option in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155], which revealed 877.8 Å(3) of solvent-accessible volume per unit cell and 126 electron-units of scattering density or 109.7 Å(3) (16 electron units) per organic mol-ecule.. This was not included in the calculations of overall formula weight, density and absorption coefficient.
    Acta Crystallographica Section E Structure Reports Online 07/2012; 68(Pt 7):o2019. · 0.35 Impact Factor
  • Source
    Islam Ullah Khan, Ejaz, Sidra Farid, William T A Harrison
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(14)H(13)ClN(2)O(5)S(2), the dihedral angles between the central benzene ring and the pendant chloro-benzene ring and the N-acetyl group are 82.35 (5) and 79.71 (6)°, respectively, and the overall conformation of the mol-ecule approximates to a U shape. Both the C-S-N-C conformations are gauche, but with opposite senses [torsion angles = -59.29 (15) and 63.68 (16)°]. An intra-molecular C-H⋯O inter-action generates an S(6) ring. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R(2) (2)(20) loops. A second N-H⋯O hydrogen bond links the dimers into (101) layers.
    Acta Crystallographica Section E Structure Reports Online 06/2012; 68(Pt 6):o1913. · 0.35 Impact Factor
  • Source
    Ejaz, Islam Ullah Khan, Alina Murtaza, William T A Harrison
    [Show abstract] [Hide abstract]
    ABSTRACT: In the monomeric title complex, [Cu(C(4)H(5)O(2))(2)(C(8)H(11)N)(2)], the Cu(II) atom lies on a centre of inversion. Its coordination by two substituted pyridine ligands and two carboxyl-ate anions leads to a slightly distorted trans-CuN(2)O(2) square-planar geometry. The dihedral angle between the mean planes of the pyridine (py) ring and the carboxyl-ate group is 74.71 (7)°. The dihedral angles between the planar CuN(2)O(2) core and the py ring and carboxyl-ate plane are 67.72 (5) and 89.95 (5)°, respectively. Based on the refined C=C and C-C bond lengths, the terminal =CH(2) and -CH(3) groups of the carboxyl-ate anion may be disordered, but the disorder could not be resolved in the present experiment. Several intra-molecular C-H⋯O inter-actions occur. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, generating chains propagating in [100].
    Acta Crystallographica Section E Structure Reports Online 04/2012; 68(Pt 4):m469-70. · 0.35 Impact Factor
  • Source
    Ejaz, Islam Ullah Khan, William T A Harrison, Rukhsana Anjum
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(22)H(24)N(2)O(4)S(2), the dihedral angles between the central benzene ring and the pendant rings are 66.96 (13) and 69.37 (13)°. The torsion angles for the C-N-S-C fragments are -68.5 (3) and -72.6 (3)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds to generate infinite (001) sheets containing R(4) (4)(28) loops. A weak aromatic π-π stacking contact between one of the terminal benzene rings and its inversion-related partner is also observed [centroid-to-centroid separation = 3.796 (2) Å and slippage = 1.581 Å], as are two possible C-H⋯π contacts.
    Acta Crystallographica Section E Structure Reports Online 04/2012; 68(Pt 4):o950. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title compound, C(16)H(10)Cl(2)F(3)N(3)S, the dihedral angle between the quinoline and thio-phene ring systems is 4.94 (10)°. The NH group of the hydrazone moiety does not form a hydrogen bond, due to a steric crowding. In the crystal, the thio-phene ring takes part in weak π-π stacking inter-actions with the pyridine ring [centroid-to-centroid separation = 3.7553 (19) Å and inter-planar angle = 5.48 (12)°] and the benzene ring [3.7927 (19) Å and 4.58 (12)°]. Together, these lead to [100] stacks of mol-ecules in an alternating head-to-tail arrangement, with two π-π stacking contacts between each adjacent pair.
    Acta Crystallographica Section E Structure Reports Online 03/2012; 68(Pt 3):o790. · 0.35 Impact Factor

Publication Stats

823 Citations
447.92 Total Impact Points

Institutions

  • 2013
    • The American University in Cairo
      • Department of Chemistry
      Cairo, Muhafazat al Qahirah, Egypt
    • Government College University Faisalabad
      • Department of Chemistry
      Faisalābād, Punjab, Pakistan
    • Gomal University
      • Department of Chemistry
      Dera Ismāīl Khān, North West Frontier Province, Pakistan
  • 2012
    • Government College University, Lahore
      • Department of Chemistry
      Lahore, Punjab, Pakistan
    • Uludag University
      • Department of Chemistry
      United States
  • 1999–2012
    • University of Aberdeen
      • Department of Chemistry
      Aberdeen, SCT, United Kingdom
  • 2008
    • University of Southampton
      • Faculty of Natural and Environmental Sciences
      Southampton, ENG, United Kingdom
    • Gorgan University of Agricultural Sciences and Natural Resources
      • Department of Soil Sciences
      Asterābād, Golestān, Iran
  • 2007
    • St Aloysius College
      Mangalur, Karnātaka, India
  • 1988–2006
    • University of California, Santa Barbara
      • • Materials Research Laboratory
      • • Department of Chemistry and Biochemistry
      Santa Barbara, CA, United States
  • 2002–2005
    • Federal University of Rio de Janeiro
      • Departamento de Química Inorgânica
      Rio de Janeiro, Rio de Janeiro, Brazil
  • 1997–2005
    • University of Western Australia
      • School of Chemistry and Biochemistry
      Perth, Western Australia, Australia
  • 2004
    • University of the West of Scotland
      Пейсли, Scotland, United Kingdom
  • 2001–2004
    • Ondokuz Mayıs Üniversitesi
      • Faculty of Arts and Sciences
      Djanik, Samsun, Turkey
  • 1993–1996
    • University of Houston
      • Department of Chemistry
      Houston, TX, United States
  • 1995
    • National Institute of Standards and Technology
      Maryland, United States
  • 1985–1992
    • University of Oxford
      • Inorganic Chemistry Laboratory
      Oxford, England, United Kingdom