Chidan Kumar C S | Universiti Sains Malaysia (original) (raw)
Papers by Chidan Kumar C S
Acta crystallographica. Section E, Structure reports online, 2010
The title compound, C(13)H(13)F(2)N(6)O(+)·C(6)H(2)N(3)O(7) (-), is the first structurally charac... more The title compound, C(13)H(13)F(2)N(6)O(+)·C(6)H(2)N(3)O(7) (-), is the first structurally characterized salt of the cation of fluconazole [systematic name 2-(2,4-difluorophenyl)-1,3-bis(1H-1,2,4-triazol-1-yl)propan-2-ol], a synthetic anti-fungal agent. In the crystal, the components are linked by O-H⋯O hydrogen bonding between the hy-droxy group of the fluconazolium cation and the C=O(-) group of the picrate anion. This complex is additionally stabilized by secondary, but relatively short, C-H⋯O inter-actions. The dimers thus formed are connected by N-H⋯N cation-cation hydrogen bonds into helices running along [010]. Neighboring helices of opposite handedness are joined by weak anion-anion C-H⋯O(nitro) inter-actions. In the cation, the mean planes of the three rings are approximately, within ca 25°, parallel to the central C-O bond. In the picrate anion two nitro groups, in turn, are almost coplanar with the ring plane [forming dihedral angles of 6.5 (2) and 3.8 (2)°] while the third nitro group is significantly twisted [by 46.79 (13)°].
Acta crystallographica. Section E, Structure reports online, 2009
In the title compound, C(21)H(15)BrO, there are two planar rings connected through a conjugated d... more In the title compound, C(21)H(15)BrO, there are two planar rings connected through a conjugated double bond. As it crystallizes in a non-centrosymmetric space group it can be regarded as a good candidate for non-linear optical applications. The mol-ecule adopts an E configuration and the C-C=C-C torsion angle is 177.1 (4)°. The overall conformation of the compound may be described by the values of dihedral angles between the approximately planar parts. The terminal rings are twisted by an angle of 51.52 (9)°, while the biphenyl part is almost planar, the dihedral angle between the planes of the rings being 4.44 (17)°. The unit cell has one long dimension, above 35 Å, characteristic also of a majority of related compounds. The mol-ecules pack head-to-tail along this direction. C-H⋯π inter-actions are observed in the crystal structure.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(18)H(12)Cl(2)O(2)S, the dihedral angle between the thio-phene ring and t... more In the title compound, C(18)H(12)Cl(2)O(2)S, the dihedral angle between the thio-phene ring and the naphthalene ring system is 2.13 (4)°. In the crystal, pairs of weak inter-molecular C-H⋯O hydrogen bonds form centrosymmetric dimers.
Acta crystallographica. Section E, Structure reports online, 2010
Key indicators: single-crystal X-ray study; T = 291 K; mean (C-C) = 0.006 Å; R factor = 0.038; wR... more Key indicators: single-crystal X-ray study; T = 291 K; mean (C-C) = 0.006 Å; R factor = 0.038; wR factor = 0.091; data-to-parameter ratio = 15.6.
Acta crystallographica. Section E, Structure reports online, 2011
In the title compound, C(13)H(9)FN(4)O(4), the dihedral angle between the mean planes of the two ... more In the title compound, C(13)H(9)FN(4)O(4), the dihedral angle between the mean planes of the two benzene rings of the nearly planar mol-ecule is 6.6 (9)°. The dihedral angles between the mean planes of the benzene ring and its two attached nitro groups are 6.7 (7) and 7.2 (9)°. Crystal packing is stabilized by N-H⋯O hydrogen bonds, weak C-H⋯O and C-H⋯F inter-molecular inter-actions and centroid-centroid π-ring stacking inter-actions.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(15)H(13)Cl(2)NOS, the benzene and thio-phene rings make a dihedral angle... more In the title compound, C(15)H(13)Cl(2)NOS, the benzene and thio-phene rings make a dihedral angle of 10.8 (1)°. The dimethyl-amino substituent and the α,β-unsaturated carbonyl group are almost coplanar with respect to the aromatic ring, forming dihedral angles of 4.73 (3)° and 5.0 (2)°, respectively. In the crystal structure, mol-ecules are connected into two-dimensional layers by weak C-H⋯Cl hydrogen bonds and C-Cl⋯O [Cl⋯O = 3.073 (2) Å] inter-actions. These layers are stacked with short C(meth-yl)-H⋯π contacts betweeen the layers.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(15)H(12)Cl(2)O(3)S, the prop-2-en-1-one (enone) fragment is almost plana... more In the title compound, C(15)H(12)Cl(2)O(3)S, the prop-2-en-1-one (enone) fragment is almost planar [C-C-C-O = 2.2 (4)°] and it subtends dihedral angles of 11.9 (2) and 11.0 (2)° with the thio-phene and benzene rings, respectively. The dihedral angle between the aromatic rings is 3.47 (16)°. In the crystal, weak C-H⋯O and C-H⋯Cl inter-actions link the mol-ecules, leading to R(2) (2)(14), R(2) (2)(24) and C(11) supra-molecular motifs occurring within the three-dimensional network. Weak aromatic π-π stacking [centroid-centroid separations = 3.6823 (15) and 3.8722 (15) Å] may also help to consolidate the packing.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(17)H(14)BrNO(5), the dihedral angle between the 3-bromo-substituted benz... more In the title compound, C(17)H(14)BrNO(5), the dihedral angle between the 3-bromo-substituted benzene ring and the 4,5-dimeth-oxy-2-nitro-phenyl ring is 15.2 (1)°. The dihedral angles between the mean plane of the propenone group and the mean planes of the 3-bromo-substituted benzene and 4,5-dimeth-oxy-2-nitro-phenyl rings are 6.9 (6) and 20.5 (5)°, respectively. Weak inter-molecular C-H⋯O inter-actions contribute to crystal stability and π-π inter-actions [centroid-centroid distances = 3.7072 (18) and 3.6326 (18) Å] are also observed.
Acta crystallographica. Section E, Structure reports online, 2010
Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.003 Å; disorder in main res... more Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.003 Å; disorder in main residue; R factor = 0.040; wR factor = 0.102; data-to-parameter ratio = 20.0.
![Research paper thumbnail of N-[(2-Chloro-3-quinol-yl)meth-yl]-4-fluoro-aniline](https://attachments.academia-assets.com/50072228/thumbnails/1.jpg)
](Acta crystallographica. Section E, Structure reports online, 2010
Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.002 Å; R factor = 0.034; wR... more Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.002 Å; R factor = 0.034; wR factor = 0.094; data-to-parameter ratio = 21.7.
Acta crystallographica. Section E, Structure reports online, 2011
Acta crystallographica. Section E, Structure reports online, 2012
In the title salt adduct, C(17)H(21)ClN(2) (2+)·2C(2)Cl(3)O(2) (-)·C(2)HCl(3)O(2), the Cl atom of... more In the title salt adduct, C(17)H(21)ClN(2) (2+)·2C(2)Cl(3)O(2) (-)·C(2)HCl(3)O(2), the Cl atom of the dication is disordered over two positions in a 0.915 (3):0.085 (3) ratio. The Cl atoms in the trichloroacetate anions and trichloroacetic acid molecule are also disordered, with refined site-occupation factors of 0.59 (3):0.41 (3), 0.503 (12):0.417 (12) and 0.653 (12):0.347 (12). The piperazine ring adopts a chair conformation, with puckering parameters Q(T) = 0.587 (3) Å, θ = 2.6 (2) and Φ 334 (6)°. In the crystal, neighbouring mol-ecules are linked by N-H⋯O, O-H⋯O, N-H⋯Cl, C-H⋯O and C-H⋯Cl hydrogen bonds, forming a three-dimensional network.
Acta crystallographica. Section E, Structure reports online, 2012
![Research paper thumbnail of 2-Amino-6-methyl-5-{5-[(naphthalen-2-yl-oxy)meth-yl]-1,3,4-oxadiazol-2-ylsulfan-yl}-4-(3-nitro-phen-yl)pyridine-3-carbonitrile](https://attachments.academia-assets.com/50072215/thumbnails/1.jpg)
](Acta crystallographica. Section E, Structure reports online, 2013
Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.004 Å; R factor = 0.056; wR... more Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.004 Å; R factor = 0.056; wR factor = 0.164; data-to-parameter ratio = 13.8.
![Research paper thumbnail of 4-[(4-Chloro-phen-yl)(phen-yl)-meth-yl]-piperazin-1-ium picrate monohydrate](https://attachments.academia-assets.com/50072237/thumbnails/1.jpg)
](Acta crystallographica. Section E, Structure reports online, 2012
Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.005 Å; R factor = 0.057; wR... more Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.005 Å; R factor = 0.057; wR factor = 0.175; data-to-parameter ratio = 13.2.
Journal of Chemical Crystallography, 2011
Abstract The title compound, C8H9N3O4S × 1/2(H2O), which is an impurity found in a drug lamivudin... more Abstract The title compound, C8H9N3O4S × 1/2(H2O), which is an impurity found in a drug lamivudine, crystallizes in the hexagonal space group P62 with a = 10.208(1) Å and c = 18.073(2) Å. Such a rare packing is constructed by the hierarchical network of hydrogen bonds, which connect the molecules into chains, then into pairs of chains, and neighboring chains, oriented at the angle of 60°, make the final packing mode. The molecule exists in the crystal as the zwitterion, with negative charged carboxylate and positive ammonio groups. The oxathiolane ring is close to an envelope conformation, and both pyrimidine and carboxylate substituent are in the equatorial positions. Graphical Abstract The hexagonal packing is constructed by the hierarchical network of hydrogen bonds, which connect the molecules into chains, then into pairs of chains, and neighboring chains, oriented at the angle of 60°, make the final packing mode.
Acta Crystallographica Section E-structure Reports Online, 2009
Sugar Tech, 2008
The impact of irrigation of distillery spent on the nutrients uptake in pulses in untreated and t... more The impact of irrigation of distillery spent on the nutrients uptake in pulses in untreated and treated soil were studied. The 50% and 33% concentrations of spent wash were analyzed for their additive plant nutrients such as nitrogen, phosphorous, potassium and other physical and chemical parameters. The pulse seeds (Namadhari and Mayhco) were sown in the prepared land and irrigated with raw water (RW), 50% and 33% spent wash, respectively. The impact of spent wash in untreated and treated soils on proximate principles (moisture, protein, fat, fiber, carbohydrate, energy, calcium, phosphorous and iron) vitamin content (carotene and vitamin-C) and mineral and trace elements (magnesium, sodium, potassium, copper, manganese, zinc, chromium and nickle) of pulses were also investigated. It was found that the uptake of all the nutrients was surplus in 33% spent wash as compared to 50% spent wash treatment and raw water irrigation (control). Aslo, the nutrients uptake was largely influenced in spent wash treated soils in comparison to raw water irrigation than the untreated soil.
![Research paper thumbnail of 3Methyl1,2,4-triazolo[3,4- a ]phthalazine monohydrate](https://attachments.academia-assets.com/50114205/thumbnails/1.jpg)
](Acta Crystallographica Section E-structure Reports Online, 2009
Acta Crystallographica Section E-structure Reports Online, 2010
Acta crystallographica. Section E, Structure reports online, 2010
The title compound, C(13)H(13)F(2)N(6)O(+)·C(6)H(2)N(3)O(7) (-), is the first structurally charac... more The title compound, C(13)H(13)F(2)N(6)O(+)·C(6)H(2)N(3)O(7) (-), is the first structurally characterized salt of the cation of fluconazole [systematic name 2-(2,4-difluorophenyl)-1,3-bis(1H-1,2,4-triazol-1-yl)propan-2-ol], a synthetic anti-fungal agent. In the crystal, the components are linked by O-H⋯O hydrogen bonding between the hy-droxy group of the fluconazolium cation and the C=O(-) group of the picrate anion. This complex is additionally stabilized by secondary, but relatively short, C-H⋯O inter-actions. The dimers thus formed are connected by N-H⋯N cation-cation hydrogen bonds into helices running along [010]. Neighboring helices of opposite handedness are joined by weak anion-anion C-H⋯O(nitro) inter-actions. In the cation, the mean planes of the three rings are approximately, within ca 25°, parallel to the central C-O bond. In the picrate anion two nitro groups, in turn, are almost coplanar with the ring plane [forming dihedral angles of 6.5 (2) and 3.8 (2)°] while the third nitro group is significantly twisted [by 46.79 (13)°].
Acta crystallographica. Section E, Structure reports online, 2009
In the title compound, C(21)H(15)BrO, there are two planar rings connected through a conjugated d... more In the title compound, C(21)H(15)BrO, there are two planar rings connected through a conjugated double bond. As it crystallizes in a non-centrosymmetric space group it can be regarded as a good candidate for non-linear optical applications. The mol-ecule adopts an E configuration and the C-C=C-C torsion angle is 177.1 (4)°. The overall conformation of the compound may be described by the values of dihedral angles between the approximately planar parts. The terminal rings are twisted by an angle of 51.52 (9)°, while the biphenyl part is almost planar, the dihedral angle between the planes of the rings being 4.44 (17)°. The unit cell has one long dimension, above 35 Å, characteristic also of a majority of related compounds. The mol-ecules pack head-to-tail along this direction. C-H⋯π inter-actions are observed in the crystal structure.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(18)H(12)Cl(2)O(2)S, the dihedral angle between the thio-phene ring and t... more In the title compound, C(18)H(12)Cl(2)O(2)S, the dihedral angle between the thio-phene ring and the naphthalene ring system is 2.13 (4)°. In the crystal, pairs of weak inter-molecular C-H⋯O hydrogen bonds form centrosymmetric dimers.
Acta crystallographica. Section E, Structure reports online, 2010
Key indicators: single-crystal X-ray study; T = 291 K; mean (C-C) = 0.006 Å; R factor = 0.038; wR... more Key indicators: single-crystal X-ray study; T = 291 K; mean (C-C) = 0.006 Å; R factor = 0.038; wR factor = 0.091; data-to-parameter ratio = 15.6.
Acta crystallographica. Section E, Structure reports online, 2011
In the title compound, C(13)H(9)FN(4)O(4), the dihedral angle between the mean planes of the two ... more In the title compound, C(13)H(9)FN(4)O(4), the dihedral angle between the mean planes of the two benzene rings of the nearly planar mol-ecule is 6.6 (9)°. The dihedral angles between the mean planes of the benzene ring and its two attached nitro groups are 6.7 (7) and 7.2 (9)°. Crystal packing is stabilized by N-H⋯O hydrogen bonds, weak C-H⋯O and C-H⋯F inter-molecular inter-actions and centroid-centroid π-ring stacking inter-actions.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(15)H(13)Cl(2)NOS, the benzene and thio-phene rings make a dihedral angle... more In the title compound, C(15)H(13)Cl(2)NOS, the benzene and thio-phene rings make a dihedral angle of 10.8 (1)°. The dimethyl-amino substituent and the α,β-unsaturated carbonyl group are almost coplanar with respect to the aromatic ring, forming dihedral angles of 4.73 (3)° and 5.0 (2)°, respectively. In the crystal structure, mol-ecules are connected into two-dimensional layers by weak C-H⋯Cl hydrogen bonds and C-Cl⋯O [Cl⋯O = 3.073 (2) Å] inter-actions. These layers are stacked with short C(meth-yl)-H⋯π contacts betweeen the layers.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(15)H(12)Cl(2)O(3)S, the prop-2-en-1-one (enone) fragment is almost plana... more In the title compound, C(15)H(12)Cl(2)O(3)S, the prop-2-en-1-one (enone) fragment is almost planar [C-C-C-O = 2.2 (4)°] and it subtends dihedral angles of 11.9 (2) and 11.0 (2)° with the thio-phene and benzene rings, respectively. The dihedral angle between the aromatic rings is 3.47 (16)°. In the crystal, weak C-H⋯O and C-H⋯Cl inter-actions link the mol-ecules, leading to R(2) (2)(14), R(2) (2)(24) and C(11) supra-molecular motifs occurring within the three-dimensional network. Weak aromatic π-π stacking [centroid-centroid separations = 3.6823 (15) and 3.8722 (15) Å] may also help to consolidate the packing.
Acta crystallographica. Section E, Structure reports online, 2010
In the title compound, C(17)H(14)BrNO(5), the dihedral angle between the 3-bromo-substituted benz... more In the title compound, C(17)H(14)BrNO(5), the dihedral angle between the 3-bromo-substituted benzene ring and the 4,5-dimeth-oxy-2-nitro-phenyl ring is 15.2 (1)°. The dihedral angles between the mean plane of the propenone group and the mean planes of the 3-bromo-substituted benzene and 4,5-dimeth-oxy-2-nitro-phenyl rings are 6.9 (6) and 20.5 (5)°, respectively. Weak inter-molecular C-H⋯O inter-actions contribute to crystal stability and π-π inter-actions [centroid-centroid distances = 3.7072 (18) and 3.6326 (18) Å] are also observed.
Acta crystallographica. Section E, Structure reports online, 2010
Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.003 Å; disorder in main res... more Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.003 Å; disorder in main residue; R factor = 0.040; wR factor = 0.102; data-to-parameter ratio = 20.0.
Acta crystallographica. Section E, Structure reports online, 2010
Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.002 Å; R factor = 0.034; wR... more Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.002 Å; R factor = 0.034; wR factor = 0.094; data-to-parameter ratio = 21.7.
Acta crystallographica. Section E, Structure reports online, 2011
Acta crystallographica. Section E, Structure reports online, 2012
In the title salt adduct, C(17)H(21)ClN(2) (2+)·2C(2)Cl(3)O(2) (-)·C(2)HCl(3)O(2), the Cl atom of... more In the title salt adduct, C(17)H(21)ClN(2) (2+)·2C(2)Cl(3)O(2) (-)·C(2)HCl(3)O(2), the Cl atom of the dication is disordered over two positions in a 0.915 (3):0.085 (3) ratio. The Cl atoms in the trichloroacetate anions and trichloroacetic acid molecule are also disordered, with refined site-occupation factors of 0.59 (3):0.41 (3), 0.503 (12):0.417 (12) and 0.653 (12):0.347 (12). The piperazine ring adopts a chair conformation, with puckering parameters Q(T) = 0.587 (3) Å, θ = 2.6 (2) and Φ 334 (6)°. In the crystal, neighbouring mol-ecules are linked by N-H⋯O, O-H⋯O, N-H⋯Cl, C-H⋯O and C-H⋯Cl hydrogen bonds, forming a three-dimensional network.
Acta crystallographica. Section E, Structure reports online, 2012
Acta crystallographica. Section E, Structure reports online, 2013
Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.004 Å; R factor = 0.056; wR... more Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.004 Å; R factor = 0.056; wR factor = 0.164; data-to-parameter ratio = 13.8.
Acta crystallographica. Section E, Structure reports online, 2012
Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.005 Å; R factor = 0.057; wR... more Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.005 Å; R factor = 0.057; wR factor = 0.175; data-to-parameter ratio = 13.2.
Journal of Chemical Crystallography, 2011
Abstract The title compound, C8H9N3O4S × 1/2(H2O), which is an impurity found in a drug lamivudin... more Abstract The title compound, C8H9N3O4S × 1/2(H2O), which is an impurity found in a drug lamivudine, crystallizes in the hexagonal space group P62 with a = 10.208(1) Å and c = 18.073(2) Å. Such a rare packing is constructed by the hierarchical network of hydrogen bonds, which connect the molecules into chains, then into pairs of chains, and neighboring chains, oriented at the angle of 60°, make the final packing mode. The molecule exists in the crystal as the zwitterion, with negative charged carboxylate and positive ammonio groups. The oxathiolane ring is close to an envelope conformation, and both pyrimidine and carboxylate substituent are in the equatorial positions. Graphical Abstract The hexagonal packing is constructed by the hierarchical network of hydrogen bonds, which connect the molecules into chains, then into pairs of chains, and neighboring chains, oriented at the angle of 60°, make the final packing mode.
Acta Crystallographica Section E-structure Reports Online, 2009
Sugar Tech, 2008
The impact of irrigation of distillery spent on the nutrients uptake in pulses in untreated and t... more The impact of irrigation of distillery spent on the nutrients uptake in pulses in untreated and treated soil were studied. The 50% and 33% concentrations of spent wash were analyzed for their additive plant nutrients such as nitrogen, phosphorous, potassium and other physical and chemical parameters. The pulse seeds (Namadhari and Mayhco) were sown in the prepared land and irrigated with raw water (RW), 50% and 33% spent wash, respectively. The impact of spent wash in untreated and treated soils on proximate principles (moisture, protein, fat, fiber, carbohydrate, energy, calcium, phosphorous and iron) vitamin content (carotene and vitamin-C) and mineral and trace elements (magnesium, sodium, potassium, copper, manganese, zinc, chromium and nickle) of pulses were also investigated. It was found that the uptake of all the nutrients was surplus in 33% spent wash as compared to 50% spent wash treatment and raw water irrigation (control). Aslo, the nutrients uptake was largely influenced in spent wash treated soils in comparison to raw water irrigation than the untreated soil.
Acta Crystallographica Section E-structure Reports Online, 2009
Acta Crystallographica Section E-structure Reports Online, 2010