Venkatachalam Ramkumar

We don’t have enough information about this author to calculate their statistics. If you think this is an error let us know.
Learn More
The title compound, C25H29Cl2NO, which is a chloro analog of 2,4-bis-(2-bromo-phen-yl)-7-(tert-pent-yl)-3-aza-bicyclo-[3.3.1]nonan-9-one [Park, Ramkumar & Parthiban (2012). Acta Cryst. E68, o2946], exists in a twin-chair conformation with an equatorial orientation of the 2-chloro-phenyl groups. The tert-pentyl group on the cyclo-hexa-none adopts an(More)
There are two independent mol-ecules in the asymmetric unit of the title compound, C19H16N2O5S, in which the thia-zole rings make dihedral angles of 80.89 (11) and 84.81 (11)° with the pyrano[3,2-c]chromene ring systems. An intra-molecular N-H⋯O hydrogen bond involving the amino group occurs in each independent mol-ecule. In the crystal, the amino groups(More)
The linkage region constituents, 2-deoxy-2-acetamido-β-D-glucopyranose (GlcNAc) and L-asparagine (Asn) are conserved in the N-glycoproteins of all eukaryotes. Elucidation of the structure and conformation of the linkage region of glycoproteins is important to understand the presentation and dynamics of the carbohydrate chain at the protein/cell surface.(More)
trans-Bis(1,4-dimesityl-3-methyl-1,2,3-triazol-5-ylidene)palladium(II) dichloride has been shown to be an excellent catalyst for the multiple Suzuki-Miyaura coupling reactions of polybromoarenes to the corresponding fully substituted polyarylarenes. The reactions proceeded in excellent yields and with high turnover numbers. With 1,4-dibromobenzene the(More)
The mol-ecular structure of the title compound, C(14)H(18)Br(2)N(2)O(2), has one half-mol-ecule in the asymmetric unit. The mol-ecule has a crystallographic inversion centre in the middle of the benzene ring. The C-C-N-C torsion angle between the benzene ring and the bromo-amide group is 149.2 (7)°. The crystal is stabilized by a strong inter-molecular(More)
In the title compound, C(38)H(31)Cl(4)N(3)O·C(3)H(6)O, the 3,7-diaza-bicycle exists in a chair-boat conformation. The 4-chloro-phenyl groups attached to the chair form are equatorially oriented at an angle of 18.15 (3)° with respect to each other, whereas the 4-chloro-phenyl groups attached to the boat form are oriented at an angle of 32.64 (3)°. In the(More)
The piperidin-4-one ring in the title compound, C(26)H(26)Cl(2)N(2)O, exists in a chair conformation with equatorial orientations of the methyl and 4-chlorophenyl groups. The C atom bonded to the oxime group is statistically planar (bond-angle sum = 360.0°) although the C-C=N bond angles are very different [117.83 (15) and 127.59 (15)°]. The dihedral angle(More)
The central ring of the title compound, C(28)H(32)N(2)O(3), exists in a chair conformation with an equatorial disposition of all the alkyl and aryl groups on the heterocycle. The para-anisyl groups on both sides of the secondary amino group are oriented at an angle of 54.75 (4)° with respect to each other. The oxime derivative exists as an E isomer with the(More)