Faculty Publications
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Item 5-Diethyl-amino-2-[(E)-(4-methyl-3-nitro-phenyl)-imino-meth-yl]phenol: A redetermination(2009) Fun, H.-K.; Kia, R.; Vijesh, A.M.; Isloor, A.M.The title compound, C18H21N3O3, is a potential bidentate Schiff base ligand. The whole mol-ecule is disordered with a refined site-occupancy ratio of 0.567 (4):0.433 (4) and not just one ethyl group as reported previously [Sarojini et al. (2007). Acta Cryst. E63, o4782-o4782]. Using the whole mol-ecule disorder, R values are much smaller than those published. An intra-molecular O - H?N hydrogen bond generates a six-membered ring, producing an S(6) ring motif. The dihedral angle between the mean plane of the two benzene rings (major component) is 9.0 (5)°. The crystal structure shows short C?C [3.189 (15)-3.298 (12) Å] and C?O [2.983 (5)-3.149 (13) Å] contacts. Inter-molecular C - H?O inter-actions link neighbouring mol-ecules into dimers with R 2 2(18) motifs. In the crystal structure, these dimers are linked together by inter-molecular C - H?O inter-actions into one-dimensional extended chains along the b axis. The crystal structure is further stabilized by inter-molecular ?-? stacking inter-actions [centroid-centroid distances = 3.458 (8)-3.691 (6) Å].Item 2-[(4-tert-Butyl-anilino)(phen-yl)meth-yl]cyclo-hexa-none(2009) Fun, H.-K.; Chantrapromma, S.; Rai, S.; Shetty, P.; Isloor, A.M.In the mol-ecule of the title compound, C23H29NO, the cyclo-hexa-none ring has been distorted from the standard chair conformation by the ketone group such that part of the ring is almost flat. The remaining [(4-tert-butyl-anilino)(phen-yl)meth-yl] portion of the mol-ecule is in an equatorial position on the cyclo-hexa-none ring. The dihedral angle between the two benzene rings is 81.52 (8)°. In the crystal packing, mol-ecules are linked by N - H?O hydrogen bonds into infinite one-dimensional chains along the a axis and these chains are stacked down the c axis. The crystal structure is further stabilized by weak C - H?O and C - H?? inter-actions.Item N-(1-Naphth-yl)-10H-9-oxa-1,3-diaza-anthracen-4-amine(2009) Fun, H.-K.; Chantrapromma, S.; Rai, S.; Shetty, P.; Isloor, A.M.In the mol-ecule of the title compound, C21H15N 3O, the 10H-9-oxa-1,3-diaza-anthracene ring system is slightly bent, with dihedral angles of 3.99 (6) and 4.80 (6)° between the pyran ring and the pyrimidine and benzene rings, respectively. This ring system makes a dihedral angle of 85.23 (3)° with the naphthalene plane. In the crystal packing, mol-ecules are linked by N - H?N hydrogen bonds into chains along the a axis and these chains are stacked along the b axis. The crystal is further stabilized by weak C - H?N and C - H?? inter-actions.Item (4-Chloro-2-fluoro-phen-yl)[1-(2,6-difluoro-phen-yl)but-3-en-yl]amine(2009) Fun, H.-K.; Rai, S.; Shetty, P.; Isloor, A.M.; Chantrapromma, S.In the mol-ecule of the title homoallylic amine, C16H 13ClF3N, the dihedral angle between the two benzene rings is 84.63 (4)°. Weak intra-molecular N - H?F hydrogen bonds generate S(6) and S(5) ring motifs. In the crystal structure, weak inter-molecuar N - H?F hydrogen bonds link mol-ecules into centrosymmetric dimers which are arranged in mol-ecular sheets parallel to the ac plane.Item Ethyl 2-[(4-chloro-phen-yl)hydrazono]-3-oxobutanoate(2009) Fun, H.-K.; Chantrapromma, S.; Padaki, M.; Radhika; Isloor, A.M.The mol-ecule of the title oxobutanoate derivative, C12H 13ClN2O3, is nearly planar; the inter-planar angle between the benzene ring and the mean plane through the hydrazono-3-oxobutanoate unit is 2.69 (3)°. An intra-molecular N - H?O hydrogen bond generates an S(6) ring motif. In the crystal packing, C - H?O(3-oxo) inter-actions link mol-ecules into dimers. The dimers thus formed are linked through C - H?O(carboxyl-ate C=O) inter-actions, leading to the formation of ribbons along the [01 ] direction, which are stabilized via Cl?Cl [3.2916 (3) Å] contacts. The ribbons are stacked via C?O contacts [3.2367 (12)-3.3948 (12) Å].Item Redetermination of methyl 3,4-O-isopropyl-idene-?-D-fucopyran-oside monohydrate(2009) Fun, H.-K.; Jebas, S.R.; Rai, S.; Shetty, P.; Isloor, A.M.In the title compound, C10H18O5· H2O, the fucopyran-oside ring adopts a chair conformation. The crystal packing is stabilized by inter-molecular O - H?O and C - H?O hydrogen bonds together with intra-molecular O?O [2.2936 (8) Å] and inter-molecular O?O [2.7140 (8)-2.829 (3) Å] short contacts. The mol-ecules are linked together to form an infinite chain along the a axis. This structure has been solved previously but with no R-values [Spiers (1931). Z. Kristallogr. Kristallgeom. Kristallphys. Kristallchem. 78, 101].Item (Z)-1-(2,5-Dichloro-3-thien-yl)ethanone semicarbazone(2009) Fun, H.-K.; Ching Kheng, C.K.; Vijesh, A.M.; Hegde, C.; Isloor, A.M.The title mol-ecule, C7H7Cl2N 3OS, is approximately planar [maximum deviation = 0.062 (1) Å]. Short inter-molecular distances between the centroids of the five-membered rings [3.5340 (8) Å] indicate the existence of ?-? inter-actions. An inter-esting feature of the crystal structure is the presence of short intra-molecular Cl?N inter-actions [3.0015 (11) Å]. Mol-ecules are linked via pairs of inter-molecular N - H?O hydrogen bonds, generating R 2 2(8) ring motifs. Furthermore, N - H?O hydrogen bonds form R 2 1(7) ring motifs with C - H?O contacts, further consolidating the crystal structure. In the crystal, mol-ecules are linked by these inter-molecular inter-actions, forming chains along [001]. © 2009 Fun et al.Item Catena-Poly[[(ethanol-O)[3-(1-phenyl-1H-pyrazol-3-yl)benzoic acid-O]lithium] - 3-(1-phenyl-1H-pyrazol-3-yl)benzoato-2 O:O?](2009) Fun, H.-K.; Balasubramani, K.; Rai, S.; Shetty, P.; Isloor, A.M.The asymmetric unit of the title polymeric compound, [Li2(C 16H11N2O2)2(C 16H12N2O2)2(CH 3CH2OH)2] n , contains two Li I ions, two 3-(1-phenyl-1H-pyrazol-3-yl)benzoate ions, two 3-(1-phenyl-1H-pyrazol-3-yl)benzoic acid molecules and two ethanol molecules. In the crystal structure, each of the two LiI ions has a distorted tetra-hedral geometry, coordinated by two carboxyl-ate O atoms, one carboxyl O atom and one ethanol O atom. The carboxyl-ate group bridges the LiI ions, forming a one-dimensional polymeric chain along [100]. The crystal structure is further stabilized by O - H?O and C - H?N hydrogen bonding, and ?-? inter-actions with centroid-centroid distances in the range 3.6534 (13)-3.8374 (13) Å. © 2009 Fun et al.Item (E)-1-(4-Chloro-phen-yl)ethanone semi-carbazone(2009) Fun, H.-K.; Ching Kheng, C.K.; Padaki, M.; Malladi, S.; Isloor, A.M.In the title compound, C9H10ClN3O, the semicarbazone group is approximately planar, with an r.m.s. deviation from the mean plane of 0.054 (1) Å. The dihedral angle between the least-squares planes through the semicarbazone group and the benzene ring is 30.46 (5)°. In the solid state, mol-ecules are linked via inter-molecular N - H?O and N - H?N hydrogen bonds, generating R22(9) ring motifs which, together with R22(8) ring motifs formed by pairs of inter-molecular N - H?O hydrogen bonds, lead to the formation of a seldom-observed mol-ecular trimer. Furthermore, N - H?O hydrogen bonds form R21(7) ring motifs with C - H?O hydrogen bonds, further consolidating the crystal structure. Mol-ecules are linked by these inter-molecular inter-actions, forming two-dimensional networks parallel to (100).Item An ortho-rhom-bic polymorph of 6-de-oxy-6-iodo-1,2:3,4-di-O-isopropyl-idene - D-galactopyran-oside(2009) Fun, H.-K.; Liew, W.-C.; Rai, S.; Shetty, P.; Isloor, A.M.The title compound, C12H19IO5, is the ortho-rhom-bic polymorph of a previously reported monoclinic form [Krajewski et al. (1987). Bull. Pol. Acad. Sci. Chem. 35, 91-102]. The dihedral angles between the six-membered ring and the two five-membered rings are 67.66 (14) and 71.79 (13)°, whereas the dihedral angle between the five-membered rings is 74.41 (12)°, indicating that all three rings are twisted from each other. The six-membered ring has a twist-boat conformation while both of the five-membered rings have envelope conformations. The crystal structure is stabilized by a network of C - H?O contacts linking the mol-ecules into a two-dimensional array parallel to the ab plane. © 2009 Fun et al.