254 research outputs found
Synthesis, characterization and bio-activity of metal complexes of bidentate N-S isomeric Schiff bases derived from S-methyldithiocarbazate (SMDTC) and the X-ray structure of the bis[S-methyl-β-N-(2-furyl-methylketone) dithiocarbazato]cadmium(II) complex.
Condensation of SMDTC with 2-furyl-methylketone and 5-methyl-2-furaldehyde gave isomeric Schiff bases, (NS) and (NS'). The metal complexes of these uninegatively charged bidentate Schiff base ligands with cadmium, tin, iron, lead and cobalt have been prepared. The complexes have been characterized by a variety of physico-chemical techniques. X-ray crystallographic analysis shows that the Cd(II) complex, bis[S-methyl-β-N-(2-furylmethylketone)dithiocarbazato]cadmium(II), consists of two molecules with distorted octahedral structure. The Co(II) complexes are paramagnetic with a square-planar stereochemistry. The diamagnetic Sn(II), Fe(III) and Pb(II) complexes also have square-planar structures while the diamagnetic [Cd(NS')2]. 3H2O complex is tetrahedral. The [Cd(NS')2].3H2O, [Sn(N'S)2) and [Co(NS)2] showed clear inhibition of almost all bacteria and fungi tested However, [Cd(NS)2], [Fe(NS)]Cl2, [Pb(NS)2] and [Pb(NS')2] were inactive against all bacteria assayed while [Cd(NS)2], [Fe(NS)]Cl2 and [Pb(NS)2] showed clear inhibition of some fungi. The [Cd(NS)2], [Cd(NS')2].3H2O and [Co(NS)2] were found to be very active against Human cell T-lymphoblastic leukemia (CEM-SS) and cervical cancer cells (HELA) with CD50 values between 1.8 and 3.6 μl cm-3
Substituted Methoxybenzene derivatives: C8H9NO4, C9H11NO5 and C13H18O4
The structures of three methoxybenzenes, namely 1,2-dimethoxy-4-nitrobenzene, C8H9NO4, (I), 1,2,3-trimethoxy-5-nitrobenzene, C9H11NO5, (II), and 1-(2,4,5-trimethoxyphenyl)-1-butanone, C13H18O4, (III), are reported. Molecules of (I) and (III) are planar, but one of the three methoxy groups of (II) is twisted out of the phenyl ring plane as a result of steric hindrance. In all three solids, the molecules are linked to form centrosymmetrically hydrogen-bonded dimers; they are packed in parallel layers in (I) and (II), but in zigzag layers in (III)
Benzyl 3-[(E,E)-3-phenylprop-2-enylidene]dithiocarbazate
The title compound, C17H16N2S2, a dithiocarbazate derivative, adopts an EE configuration with respect to the C=C and C=N double bonds of the propenylidine group. The 3-phenylprop-2-enylidene and dithiocarbazate fragments lie essentially in the same plane, with a maximum deviation from that plane of 0.074 (2) Å, while the dihedral angle between the 3-phenylprop-2-enylidene and the benzyl group is 77.78 (7)°. In the crystal structure, molecules are linked by an N—H⋯S hydrogen bond and a weak C—H⋯S interaction involving the terminal thione S atom, forming dimers that are arranged into sheets parallel to the bc plane. The crystal structure is also stabilized by C—H⋯π interactions
(2E)-1-(2-Bromophenyl)-3-(4-chlorophenyl)prop-2-en-1-one
In the title compound, C15H10BrClO, the dihedral angle between the mean planes of the benzene rings in the ortho-bromo- and para-chloro-substituted rings is 70.5 (6)°. The dihedral angles between the mean plane of the prop-2-en-1-one group and the mean planes of the benzene rings in the 4-chlorophenyl and 2-bromophenyl rings are 14.9 (3) and 63.3 (8)°, respectively. In the crystal, inversion dimers linked by pairs of weak C—H⋯O interactions are observed as well as aromatic π–π stacking interactions
(E)-4-(Benzyloxy)benzaldehyde thiosemicarbazone
In the title compound, C15H15N3OS, the thiosemicarbazone group adopts an E configuration with respect to the C=N bond. The benzaldehyde thiosemicarbazone fragment is almost planar [maximum deviation = 0.012 (1) Å], while the dihedral angle between the benzyloxy and phenyl rings is 72.48 (5)°. In the crystal structure, molecules are interconnected by N—H⋯N and N—H⋯S hydrogen bonds, forming a two-dimensional network parallel to the bc plane and are further stacked along the a axis by π–π interactions [centroid–centroid separation 3.9043 (7) Å]. The crystal structure is also stabilized by C—H⋯π interactions
Synthesis, structural and antioxidant studies of some novel n-ethyl phthalimide esters
A series of N-ethyl phthalimide esters 4(a-n) were synthesized and characterized by spectroscopic studies. Further, the molecular structure of majority of compounds were analysed by single crystal X-ray diffraction studies. The X-ray analysis revealed the importance of substituents on the crystal stability and molecular packing. All the synthesized compounds were tested for in vitro antioxidant activity by DPPH radical scavenging, FRAP and CUPRAC methods. Few of them have shown good antioxidant activity
A second polymorph of (2E)-1-(4-fluorophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one
The crystal structure of the title compound, C18H17FO4, reported here is a polymorph of the structure first reported by Patil et al. [Mol. Cryst. Liq. Cryst. Sci. Technol. Sect. A (2007), 461, 123–130]. It is a chalcone analog and consists of substituted phenyl rings bonded at the opposite ends of a propenone group, the biologically active region. The dihedral angle between the mean planes of the aromatic rings within the 4-fluorophenyl and trimethoxyphenyl groups is 28.7 (1)° compared to 20.8 (6)° in the published structure. The angles between the mean plane of the prop-2-ene-1-one group and the mean plane of aromatic rings within the 4-fluorophenyl and trimethoxyphenyl groups are 30.3 (4) and 7.4 (7)°, respectively, in contast to 10.7 (3) and 12.36° for the polymorph. While the two 3-methoxy groups are in the plane of the trimethoxy-substituted ring, the 4-methoxy group is in a synclinical [−sc = −78.1 (2)°] or anticlinical [+ac = 104.0 (4)°] position, compared to a +sc [53.0 (4)°] or −ac [−132.4 (7)°] position. While no classical hydrogen bonds are present, weak intermolecular C—H⋯π-ring interactions are observed which contribute to the stability of the crystal packing. The two polymorphs crystallize in the same space group, P21/c, but have different cell parameters for the a, b and c axes and the β angle. A comparison of the molecular geometries of both polymorphs to a geometry optimized density functional theory (DFT) calculation at the B3-LYP/6–311+G(d,p) level for each structure provides additional support to these observations
Bis{4-[(Z)-N′-(4-hydroxybenzylidene)hydrazino]-8-(trifluoromethyl)quinolinium} sulfate dihydrate
The title compound, 2C17H13F3N3O+·SO4
2−·2H2O, crystallizes with four independent cations (A, B, C and D) in the asymmetric unit, which is composed of two groups of two cations, one anion and two water molecules (Z′ = 2). The dihedral angle between the mean planes of the 4-hydroxyphenyl and quinolinium groups is 8.9 (7)° in A, 30.1 (6)° in B, 28.8 (8)° in C and 12.8 (1)° in D. The crystal packing is stabilized by intermolecular O—H⋯O and N—H⋯O hydrogen bonding between H atoms from 4-hydroxyphenyl O atoms and the O atoms of nearby water molecules and sulfate anions, as well as H atoms from the N atom of the hydrazino group to O atoms of neighboring sulfate anions, linking the components into chains with the 4-hydroxyphenyl and quinolinium rings parallel to the (011) plane. There is also an extensive array of intermolecular hydrogen bonds between water molecules themselves and with sulfate O atoms, as well as hydrogen-bond interactions between H atoms from the hydrazino group and sulfate O atoms. In addition, intermolecular π–π stacking interactions occur between nearby 4-hydroxyphenyl and quinolinium groups, with distances between the centroids of interacting rings in the range 3.4140 (9)–3.9659 (9) Å
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