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Vijayalakshmi R.,Bharathidasan University | Vijayalakshmi R.,Queen Marys College Autonomous | Muthukumar M.,Bharathidasan University | Ponnuswamy S.,Bharathidasan University | And 4 more authors.
Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry | Year: 2012

The stereochemical consequences of the introduction of A1,3-strain by means of acetyl groups in r-2,c-6- diphenylpiperidin-4-one oximes have been studied using various NMR spectral techniques, X-ray crystallographic analysis and semiempirical MO calculations. The NMR spectral results show that the N,O-diacetylpiperidin-4-one oximes 12-15 prefer to adopt twist-boat conformation with an equilibrium between syn and anti rotamers. From the variable temperature 1H NMR spectral studies carried out on N,O-diacetyl-t-3-methyl-r-2, c-6-diphenylpiperidin-4-one oxime 13, the syn-anti rotational barriers DG# AB and DG# BA have been found to be 44.2 and 43.5 kJ mol-1, respectively. The X-ray crystal structure of N,O-diacetyl-t-3-isopropyl-r-2,c-6-diphenylpiperidin-4-one oxime 14 also show twist-boat conformation. The conformational preferences obtained from the semiempirical MO calculations for N,O-diacetylpiperidin-4-one oximes 12-15 have been found to be similar to those predicted from the NMR spectral studies and X-ray crystallographic analysis. Similarly, the N-acetyl-r-2,c-6-diphenylpiperidin-4-one oximes 5-7 have been found to adopt twist-boat conformations. Source


Savithri M.P.,Queen Marys College Autonomous | Yuvaraj P.S.,University of Madras | Reddy B.S.R.,University of Madras | Raja R.,Presidency College at Chennai | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2015

In the title compound, C12H11NO4, the dihedral angle between the indole ring system (r.m.s. deviation = 0.019 Å) and the oxirane ring is 88.8 (2)°. The oxirane O atom and the bridging ester O atom are in an approximate syn conformation [O - C - C - O = - 25.4 (3)°] In the crystal, inversion dimers linked by pair of C - H⋯O hydrogen bonds generate R22(8) loops, where the C - H donor group forms part of the oxirane ring. A second C - H⋯O interaction arising from one of the C - H groups of the benzene ring links the dimers into [001] double chains. Source


Duraisamy S.,Development Consultants Private Ltd | Saminathan R.,Development Consultants Private Ltd | Narsimman D.,Queen Marys College Autonomous
Membrane Water Treatment | Year: 2015

In India, recycling of treated effluent plays a major role in the industry. Particularly in copper industry, recycling techniques for treated effluents adopt conventional technologies which are not energy efficient and recovery of high quality process water, free flowing salts and sludge's is very low. This paper presents an overview of enhanced modern technology for treated effluents in copper industry making it more efficient with high recovery of high quality process water and free flowing salts. Life cycle cost (LCC) would be 15-20% lower than the conventional technologies. The conventional technology can be replaced with this proposed technique in the existing and upcoming copper industries. © 2015 Techno-Press, Ltd. Source


Savithri M.P.,Queen Marys College Autonomous | Suresh M.,University of Madras | Raghunathan R.,University of Madras | Raja R.,Presidency College at Chennai | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2015

In the title compound, C23H22N2O4S, the pyrrolidine ring has an envelope conformation with the spiro C atom, shared with the indoline ring system, as the flap. The mean planes of the benzothiophene and indoline ring systems are inclined to the mean plane of the pyrrolidine ring by 88.81 (8) and 79.48 (8)°, respectively, and to each other by 68.12 (5)°. In the crystal, molecules are linked via C - H⋯O hydrogen bonds, forming chains propagating along [001]. Source


Savithri M.P.,Queen Marys College Autonomous | Yuvaraj P.S.,University of Madras | Reddy B.S.R.,University of Madras | Raja R.,Presidency College at Chennai | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2015

The title compound, C12H11NO3, is essentially planar, with the mean plane of the acetate side chain [-C - C(=O) - O - C] being inclined to the mean plane of the indole ring system by 12.49 (7)°. The five- and six-membered rings of the indole group are almost coplanar, making a dihedral angle of 1.76 (8)°. The conformation about the C=C bond is E and there is an intramolecular C - H⋯O hydrogen bond present. In the crystal, molecules are linked by pairs of C - H⋯O hydrogen bonds forming inversion dimers, with an R 22(16) ring motif. The dimers are linked by a second pair of C - H⋯O hydrogen bonds, enclosing R 22(16) ring motifs, forming ribbons lying parallel to (114). The ribbons are linked via C - H⋯π interactions, forming a three-dimensional structure. Source

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