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The in-crystal molecular dipole moment of the nonlinear optical material 2-methyl-4-nitroaniline has been determined from a charge density analysis of x-ray diffraction data. The results indicate a considerable enhancement of the free molecule dipole moment, due to the crystal field. The analysis suggests that aspherical pseudoatoms are essential for modeling the charge distribution in a noncentrosymmetric crystal. Careful consideration must also be given to the treatment of hydrogen atoms, in the absence of complementary neutron diffraction data. An analysis of the deformation density and Laplacian of the charge density proves useful for revealing weak hydrogen bonding effects. Ab initio calculations at the Hartree–Fock double-ζ level are reported for the molecule 2-methyl-4-nitro-aniline, with and without an applied electric field. In the former case, the magnitude and direction of the applied field were determined by a dipole lattice sum, to assess the magnitude of crystal field effects. The effect was to considerably enhance the molecular dipole moment, from 9 to 20 D, in agreement with the experimentally observed enhancement. Structure factors were generated from the ab initio wave functions and subjected to multipole refinement, to effectively project the theoretical ρ(r) into the same atom-centered multipole expansion form obtained from experiment. Monopole and dipole populations obtained in this way show convincing agreement with experiment. [ABSTRACT FROM AUTHOR]

Presents a characterization of a novel organic electro-optic crystal. Aspects in the development of a novel organic second-order nonlinear optical crystalline material; Description of the molecular design and synthesis of the electro-optic crystal; Analysis of the linear optical properties of the crystal.

A series of glutarimide derivatives which has two carbonyl coordination sites for intramolecular pentacoordination at silicon with a X1+nSiC3−nO moiety have been synthesised and characterized. The substituent (leaving group) effects on the Si–O bond exchange between the two coordination sites (resembling a pendulum) have been studied by comparison of the differently substituted (X = F, Cl, OTf, Br and I) structures. The activation parameters for the Si–O bond exchange process were measured by NMR and separately computed and are consistent with the strength of Si–O bond coordination and the nature of the leaving group, X. The temperature-dependent 29Si NMR spectroscopy is supported by X-ray crystallography and shows that the tetrahedral reactant is converted into pentacoordinate intermediates by intramolecular O–Si association followed by reversion to a tetrahedral geometry by Si–X dissociation. The two association/dissociation patterns offer a model for nucleophilic substitution at a silicon atom. A continuum of structures on the SN2 reaction profile from the glutarimide derivatives correlates reasonably well with the structural data obtained from derivatives of lactams, diketopiperazines and quinolones. [ABSTRACT FROM AUTHOR]

Ionic salts with the formulae {3[ΗBPMTU]+ · 3[X]- · nH2O} (BPMTU = 1,3-bis(3-pyridylmethyl)-2-thiourea, X = Cl- and n = 1.5 (1), X = Br-and n = 1 (2), X = I- and n = 1 (3)) were synthesized. The compounds have been characterized by elemental anaylses, TG-DTA, FT-IR, far-IR, Raman, ESI-MS and 1H, 13C-NMR spectroscopic methods, and X-ray powder diffraction techniques. The crystal structures of 1 and 2 have also been determined by X-ray diffraction at 120(2) and 100(2) K, respectively. In 1, weak lp(Cl-) → σ*(O-Η) hyperconjugative interactions and OH ··· Cl- hydrogen-bonding interactions lead to the formation of 1-D zigzag tetrameric complexes consisting of four chlorides bridged by four waters. Two oxygens of the bridging waters are also coordinated to Cl- of the complex forming a parallelogram-shaped ring. Two chlorides are also anchored by NH ··· Cl- hydrogen bonds in the free space between four tetrameric complexes. Heating 1 at 100°C for 4 h does not remove lattice water and the framework structure is retained. In 2, NH ··· Br- hydrogen-bonding interactions stabilize the supramolecular architecture. In this case, however, only two bromides are bridged by one water through OH ··· Br- hydrogen bonds. The supramolecular interactions existing in the crystal packing of the ionic salts have been analyzed at the density functional theories and ab initio CCSD(T) levels of the theory. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the silver(I) chloride complex of formula {[AgCI(CMBZT)(TPTP) 2]·(MeOH)} (1) (CMBZT = 5-chloro-2-mercaptobenzothiazole, TPTP = tris(p-tolyl)phosphine) is described. Also the structure of the hydrate derivative {[AgCI(TPTP) 3]·(0.5·H2O)} (2) of the corresponding known anhydrous silver complex (Zartilas et al., 2009), and the polymorph 3 of the known [AgI(TPTP) 3] complex (Zartilas et al., 2009) were determined and compared with the known ones. In addition, the structure of the known one silver(I) cluster {[AgI(TPTP)] 4} (4) (Meijboom et al., 2009) was re-determined at 120(2) K and possible Ag-Ag interactions were analyzed. The compounds 1-4 were characterized by X-ray crystallography at r.t (1) and 120 K (2-4). All these complexes and {[(Et3NH+)]2 · [Ag6 (µ3-Hmna) 4(µ3-mna) 2]2- · (DMSO) 2 · (H2O)} (5) (Hmna = 2- mercaptonicotinic acid) were evaluated for cytotoxic and anti-inflammatory activity. The in vitro testing of cytotoxic activity of 1--5 against leiomyosarcoma cancer cells (LMS), were evaluated with Trypan Blue and Thiazolyl Blue Tetrazolium Bromide or 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazoliumbromide (MTT) assays. The flow cytometry assay for complex 1 and showed that at 15 µM of 1, 62.38% of LMS cells undergo apoptosis, while 7% of LMS cells undergo cell necrosis. The antitumor activity of 3 is comparable with that of its reported polymorph (Zartilas et al., 2009). The anti-inflammatory, activity of complexes 1-3 and 5 was also studied. The activity towards cell viability was 2 > 3 > 5 > 1 > 4, while the order of the inhibitory activity in cell growth proliferation follows the order, 2 > 3 > 1 > 4 > 5. The anti-inflammatory activity on the other hand is 1 > 2 > 5 > … > 3. [ABSTRACT FROM AUTHOR]

The reactions of tetrachloroauric(III) acid (HAuCl4) with the thioamides; 2-mercapto-benzothiazole (mbztH) and 5-ethoxy-2-mercapto-benzimidazole (EtmbzimH) lead to the desulfuration of the ligands and the formation of the ionic complexes {[AuCl4]−[bztH2]+} (1), and {[AuCl4]−[EtbzimH2]+(H2O)} (2) (where bztH2+and EtbzimH2+are the desulfurated cations of the starting ligands). The reaction of HAuCl4with 2-mercapto-nicotinic acid (mnaH2), however results in the formation of 2-sulfonate-nicotininc acid (C6H5NO5S) (3) with the simultaneous oxidation of the sulfur atom. On the other hand, the reactions of the gold(I) complex [Au(tpp)Cl] (4) (tpp = triphenylphosphine (Ph3P)) with the thioamides; 2-mercapto-thiazolidine (mtzdH), 2-mercapto-benzothiazole (mbztH) and 5-chloro-2-mercapto-benzothiazole (ClmbztH) in the presence of potassium hydroxide resulted in the formation of the gold(I) complexes of formulae [Au(tpp)(mtzd)] (5), [Au(tpp)(mbzt)] (6) and [Au(tpp)(Clmbzt)] (7) without ligand desulfuration. All complexes have been characterized by elemental analysis, FT-IR, far-FT-IR,1H-NMR, spectroscopic techniques and X-Ray crystallography. The electrochemical behavior of 1, 2and 4-7complexes and the ligands EtmbzimH, mbztH and mnaH2was also studied in acetonitrile and DMF using cyclic voltammetry. The results are in support of a mechanism of desulfuration of the ligands by Au(III), involving a first oxidation of S to -SO3−, followed by a C-S bond cleavage. This is also supported by PM6 calculations of bond dissociation energies of the various compounds involved. Complexes 1, 2and 4-7were tested for in vitrocytotoxicity against leiomyosarcoma cells and the results are discussed in relation with the geometry of the complexes and compared with those of cisplatin and other metals. Complexes 1and 5showed higher activity than that of cisplatin, while HAuCl4was inactive against sarcoma cells. [ABSTRACT FROM AUTHOR]

Triethyl ammonium Salt of O, O′-bis( p-tolyl)dithiophosphate and O, O′-bis( m-tolyl)dithiophosphate have been obtained by reaction of p- and m-cresol, respectively with P2S5 in toluene and have been characterized by elemental analysis, IR, 1H and 31P NMR spectroscopy. The molecular structure of O, O′-bis( p-tolyl)dithiophosphate has been determined. Crystal data: [Et3NH]+[(4-MeC6H4O)2PS2]−: Monoclinic, P21/ c, a=15.2441(9) Å, b=10.415(2) Å, c=3.9726(9) Å, β=91.709(7)°, V=2217.5(1) Å−3, Z=4. [ABSTRACT FROM AUTHOR]

Purple crystals of bis( O, O′-neopentylene dithiophosphato)nickel(II), Ni[S2 $$\kern2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt}\kern-.5pt\raise10pt\hbox{\vrule height.5pt width74pt depth0pt}\hspace*{-76pt}{\rm POCH}_2{\rm CMe}_2{\rm CH}_2{\rm O}\kern-4.2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt\kern3pt}]$$ 2 and bis( O, O′-hexylene dithiophosphato)nickel(II), Ni[S2 $$\kern2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt}\kern-.5pt\raise10pt\hbox{\vrule height.5pt width83.5pt depth0pt}\hspace*{-85pt}{\rm POCMe}_2{\rm CH}_2{\rm CHMeO}\kern-4.2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt\kern3pt}]$$ 2 were obtained by layering benzene solutions of the complexes with ether and maintaining the samples at room temperature. The molecular structures of Ni[S2 $$\kern2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt}\kern-.5pt\raise10pt\hbox{\vrule height.5pt width74pt depth0pt}\hspace*{-76pt}{\rm POCH}_2{\rm CMe}_2{\rm CH}_2{\rm O}\kern-4.2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt\kern3pt}]$$ 2 and Ni[S2 $$\kern2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt}\kern-.5pt\raise10pt\hbox{\vrule height.5pt width84pt depth0pt}\hspace*{-85pt}{\rm POCMe}_2{\rm CH}_2{\rm CHMeO}\kern-4.2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt\kern3pt}]$$ 2 were determined by single-crystal X-ray diffraction. Ni[S2 $$\kern2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt}\kern-.5pt\raise10pt\hbox{\vrule height.5pt width74pt depth0pt}\hspace*{-76pt}{\rm POCH}_2{\rm CMe}_2{\rm CH}_2{\rm O}\kern-4.2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt\kern3pt}]$$ 2 crystallizes as monoclinic in the space group P21/ c with cell parameters a = 7.051(2) Å, b = 6.453(2) Å, c = 19.686(6) Å, β = 99.45(3)°, V = 883.6(5) Å−3, Z = 2, R = 0.0251, R w = 0.0599. Ni[S2 $$\kern2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt}\kern-.5pt\raise10pt\hbox{\vrule height.5pt width84pt depth0pt}\hspace*{-85pt}{\rm POCMe}_2{\rm CH}_2{\rm CHMeO}\kern-4.2pt\raise7pt\hbox{\vrule height3pt width.5pt depth0pt\kern3pt}]$$ 2 crystallizes as triclinic in the space group P-1 with cell parameters a = 8.394(5) Å, b = 11.070(5) Å, c = 12.124(5) Å, α = 71.287(5)°, β = 76.227(5)°, γ = 88.319(5)°, V = 1035.0(9) Å−3, Z = 2, R = 0.0655, R w = 0.1545. In both complexes the environment around nickel is distorted square planar. [ABSTRACT FROM AUTHOR]

A double blind controlled trial was performed on the use of topical 5% 5-fluorouracil ointment as a treatment for viral warts. The results showed the 5-fluorouracil to be better than the placebo. [ABSTRACT FROM AUTHOR]

The incidence of malignant melanoma in the Nelson-Marlborough district of New Zealand (NZ) was surveyed for six years from October 1st, 1978, and classified according to type, sex and age of patient, site, level, whether excised by surgeon or general practitioner, and whether completely or incompletely excised at the first attempt. Results show an incidence in Nelson women higher than reported in other surveys and an overall incidence comparable with the highest previously reported in the world literature. [ABSTRACT FROM AUTHOR]

A five-year-old patient with bullous ichthyosiform crythroderma is being treated with topical retinoic acid with improvement In her condition. She is now able to attend school and take her place In the community. This may be the first published account of the use of this substance In the bullous form of the condition. [ABSTRACT FROM AUTHOR]