N. Sampath

Crystal Structure and Conformation Study of 4-N,N-Dimethylamine Benzaldehyde Thiosemicarbazone Derivative

Thiosemicarbazones are N-N-S donor ligands having the ability to bind metal ions and inhibit ribonucleoside reductase, an enzyme important for DNA synthesis of all the mammalian cells. One of the important phenyl thiosemicarbazones, the title compound, has been synthesized and its stereo projection was analyzed by crystallographic methods. The X-ray data of DABT are C10H14N4S; M.W = 222.31, monoclinic, space group P21/n, a = 5.677(7)Å, b = 8.951(2)Å, c = 22.773(4)Å, β = 93.51(5)°; V = 1155.1(1)Å3, Z = 4, Dcal = 1.278 Mg/m3, λ (Cu K α ) = 1.54184 Å, final R1 and wR2 are 0.0563 and 0.1407, respectively. The molecular packing can be viewed as a dimer held together by two N-H · · · S type intermolecular hydrogen bonds. In addition to van der Waals forces, C-H · · · N, N-H · · · S, C-H · · · S, and N-H · · · N types of inter- and intramolecular hydrogen bonds facilitate the molecules in crystal packing.

Crystal Structure and Conformation of a Piperidine-Containing Thiosemicarbazone Derivative

Piperidine thiosemicarbazones have the ability to inhibit the enzyme ribonucleoside diphosphate reductase (RDR), which is essential in DNA synthesis. The present compound, t-3-methyl-r-2,c-6-diphenylpiperidin-4-one thiosemicarbazone (MDPTAN), was prepared using the Mannich reaction and crystallized with acetonitrile as solvent. The crystal data are C38H44N8S2 · 2(C2H3N); M · W = 759.06, monoclinic, space group P21/c, a = 16.324(4) A˚, b = 15.179(4) A˚, c = 17.650(5) A˚, β = 104.98(5)°, V = 4225(2) A˚3, Z = 4, Dcal = 1.193 Mgm−3, μ = 0.168 mm−1, and λ (MoKα) = 0.71073 A˚. The structure was solved by direct methods and refined to final R-values of R = 0.089 and wR = 0.1962, respectively. The piperidine rings adopt chair conformations. The planar phenyl rings are oriented equatorially at 2,6-positions of the piperidine ring. The N-H···N and C-H···N types of intra- and intermolecular hydrogen bondings play a major role in stabilizing the molecules in the unit cell. The molecular packing can be viewed as chain of dimers held together by two N-H···S types of intermolecular hydrogen bond networks. C-H···π weak interactions also support the packing of the molecules in addition to van der Waals forces.

Crystal structure of an azabicyclic thiosemicarbazone derivative

ABSTRACT The structure of 1N-nitroso-2, 6-diphenylazabicyclo[3.3.1]nonan-9-one thiosemicarbazone (NDAOT), C21H23N5OS, F.W. = 393.506, orthorhombic, Pna21, a = 8.426(3) A˚, b = 17.862(5) A˚, c = 13.313(4) A˚, V = 2003.6(1) A˚ 3, Z = 4, D cal = 1.304 M gm−3, μ = 0.183 mm−1, F(000) = 832, λ(MoKα) = 0.71073 A˚, final R1 and wR2 are 0.0501 and 0.1029, respectively. The cyclohexane and piperidine rings adopt chair–chair conformations. The phenyl rings are equatorially and bisectionally substituted at 2, 6-positions of the piperidine ring. The molecules are packed in the unit cell with the help of C–H · · · S, N–H · · · S, and N–H · · · O types of intra- and intermolecular hydrogen bondings. An intermolecular C–H · · · π interaction also plays a role in stabilizing the molecules in addition to van der Waals forces.

t-3-Isopropyl-1-methyl-r-2,c-6-diphenylpiperidin-4-one thiosemicarbazone

The piperidine ring in the title compound, C(22)H(28)N(4)S, exhibits a chair conformation. The thiosemicarbazone moiety adopts an extended conformation, and the planar phenyl rings are oriented equatorially with respect to the piperidine ring. Two intermolecular hydrogen bonds involving the S atom form molecular pairs, and the crystal structure is stabilized by weak C-H.pi interactions in addition to van der Waals forces.

Crystal Structure and Conformation of 1, 6-Dioxa[6.5]orthocyclophane-13,16-diene-15-one

1,6-Dioxa [6.5] orthocyclophane-13, 16-diene-15-one[DOCD] crystallizes in triclinic PI¯ space group and the relevant crystal data are: a = 7.577(3) A˚  , b = 10.425(5) A˚  , c = 10.935(5) A˚  , α = 87.89(1)°, β = 78.13(1)°, γ = 78.87(1)°, V = 829.4(6) A˚  3, Z = 2, Dcal = 1.283 Mg/m3. The structure was solved by direct methods and refined by least-squares procedures to a final R-value of 0.0466. The structure is 15-mer whose maximum internal cavity diameter was found to be 6.44 A˚  . The butyl group adopts a zigzag conformation. The crystal structure is stabilized by C– … O types of hydrogen bondings and C–H…π weak interactions in addition to van der Waals forces.

1,2-Bis(2-chlorophenyl)-1,2-bis(3,4-dimethyl-phenyl)ethane- ,2-diol

The asymmetric unit of the title compound, C30H28Cl2O2, contains a half molecule with the other half generated by the crystallographic twofold symmetry. The hydroxyl groups are in the trans configuration. The molecular structure is stabilized by O-H center dot center dot center dot Cl and C-H center dot center dot center dot O hydrogen bonds, and C-H center dot center dot center dot pi interactions stabilize the crystal packing.

5-Benzyl-8-(E)-benzyl­idene-6,7,7a,10a-tetra­hydro-5H-cis-cyclo­penta­[5,6]­pyrano­[3,3-c]­quinolin-6-one

In the title compound,

Crystal structure and conformation study of N-methyl-t-3-methyl- r-2, c-6-diphenylpiperidin-4-one thiosemicarbazone

C_{29}H_{23}NO_{2}

Methyl 4-oxo-r-2,c-6-di­phenyl­piperidine-3-carboxyl­ate

, the quinolinone moiety is planar and the pyran ring is in a half-chair form. The cyclopentene fused with the pyran ring adopts an envelope conformation. There are C–H...O, C–H...\pi and \pi...\pi intermolecular interactions.