946 resultados para 2,3-dicloro-6,7-dinitroquinoxalina


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Plumbogummite PbAl3(PO4)2(OH,H2O)6 is a mineral of environmental significance and is a member of the alunite-jarosite supergroup. The molecular structure of the mineral has been investigated by Raman spectroscopy. The spectra of different plumbogummite specimens differ although there are many common features. The Raman spectra prove the spectral profile consisting of overlapping bands and shoulders. Raman bands and shoulders observed at 971, 980, 1002 and 1023 cm−1 (China sample) and 913, 981, 996 and 1026 cm−1 (Czech sample) are assigned to the ν1 symmetric stretching modes of the (PO4)3−, at 1002 and 1023 cm−1 (China) and 996 and 1026 cm−1 to the ν1 symmetric stretching vibrations of the (O3POH)2− units, and those at 1057, 1106 and 1182 (China) and at 1102, 1104 and 1179 cm−1 (Czech) to the ν3 (PO4)3− and ν3 (PO3) antisymmetric stretching vibrations. Raman bands and shoulders at 634, 613 and 579 cm−1 (China) and 611 and 596 cm−1 (Czech) are attributed to the ν4 (δ) (PO4)3− bending vibrations and those at 507, 494 and 464 cm−1 (China) and 505 and 464 cm−1 (Czech) to the ν2 (δ) (PO4)3− bending vibrations. The Raman spectrum of the OH stretching region is complex. Raman bands and shoulders are identified at 2824, 3121, 3249, 3372, 3479 and 3602 cm−1 for plumbogummite from China, and at 3077, 3227, 3362, 3480, 3518 and 3601 cm−1 for the Czech Republic sample. These bands are assigned to the ν OH stretching modes of water molecules and hydrogen ions. Approximate O–H⋯O hydrogen bond lengths inferred from the Raman spectra vary in the range >3.2–2.62 Å (China) and >3.2–2.67 Å (Czech). The minority presence of some carbonate ions in the plumbogummite (China sample) is connected with distinctive intensity increasing of the Raman band at 1106 cm−1, in which may participate the ν1 (CO3)2− symmetric stretching vibration overlapped with phosphate stretching vibrations.

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In the structure of the of the phenolate salt of the sulfa drug sulfamethazine with 3,5-dinitrosalicylic acid, C12H15N4O2S+ C7H3N2O7-, the dihedral angle between the pyrimidine and phenyl rings of the cation is 59.70(17)\%. Cation--anion hydrogen-bonding interactions involving pyrimidine N+-H...O(carboxyl) and amine N-H...O(carboxyl) pairs give a cyclic R2/2(8) motif while secondary N-H...O hydrogen bonds between the aniline group and both sulfone and nitro O-atom acceptors give a two-dimensional structure extending along (001).

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Background: We have developed a sheep model of intrauterine ureaplasma infection. We aimed to examine the capability of ureaplasmas in the amniotic fluid to infect the fetus and alter fetal development...

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We hypothesized that normal human mesothelial cells acquire resistance to asbestos-induced toxicity via induction of one or more epidermal growth factor receptor (EGFR) - linked survival pathways (phosphoinositol-3-kinase/AKT/ mammalian target of rapamycin and extracellular signal - regulated kinase [ERK] 1/2) during simian virus 40 (SV40) transformation and carcinogenesis. Both isolated HKNM-2 mesothelial cells and a telomerase-immortalized mesothelial line (LP9/TERT-1) were more sensitive to crocidolite asbestos toxicity than an SV40 Tag-immortalized mesothelial line (MET5A) and malignant mesothelioma cell lines (HMESO and PPM Mill). Whereas increases in phosphorylation of AKT (pAKT) were observed in MET5A cells in response to asbestos, LP9/TERT-1 cells exhibited dose-related decreases in pAKT levels. Pretreatment with an EGFR phosphorylation or mitogen-activated protein kinase kinase 1/2 inhibitor abrogated asbestos-induced phosphorylated ERK (pERK) 1/2 levels in both LP9/TERT-1 and MET5A cells as well as increases in pAKT levels in MET5A cells. Transient transfection of small interfering RNAs targeting ERK1, ERK2, or AKT revealed that ERK1/2 pathways were involved in cell death by asbestos in both cell lines. Asbestos-resistant HMESO or PPM Mill cells with high endogenous levels of ERKs or AKT did not show dose-responsive increases in pERK1/ERK1, pERK2/ERK2, or pAKT/AKT levels by asbestos. However, small hairpin ERK2 stable cell lines created from both malignant mesothelioma lines were more sensitive to asbestos toxicity than shERK1 and shControl lines, and exhibited unique, tumor-specific changes in endogenous cell death - related gene expression. Our results suggest that EGFR phosphorylation is causally linkedto pERK and pAKT activation by asbestos in normal and SV40 Tag - immortalized human mesothelial cells. They also indicate that ERK2 plays a role in modulating asbestos toxicity by regulating genes critical to cell injury and survival that are differentially expressed in human mesotheliomas.

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The title compound, C10H7Cl2NO, features a planar molecule, excluding the methyl H atoms [maximum deviation = 0.0385 (1) angstrom]. The crystal packing is stabilized by pi-pi stacking interactions across inversion centres [centroid-to-centroid distance = 3.736 (3) angstrom].

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M r = 326.3, monoclinic, P21, a --= 6.510 (2), b=8.432 (2), c= 15.114 (2),a, /~= 101.42 (3) ° , Z = 2, V= 813.15 A 3, D x = 1-33 Mg m -3, F(000) = 172, 2(Cu Ka) = 1.5418/~,, g(Cu Ka) = 0.906 mm -~, final R = 6.4% for 1924 observed counter reflections. The conformation about the glycosidic bond is syn [torsion angle C(6)-N(1)-C(1')-O(4')=-103.9(3)°]. The sugar pucker is C(2')-exo,C(3')-endo (3Tz). The conformation about the C(4')-C(5') bond is gauche-trans. An uncommon intermolecular hydrogen bond involving the ribose-ring oxygen O(1') and the base-nitrogen N(3) stabilizes the crystal structure.

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CIoH15NO282, Mr=245"0, orthorhombic, P21212 ~, a = 6.639 (2), b = 8.205 (2), c = 22.528(6)A, V= I227.2(6)A 3, z=4, Dm= 1.315, Dx= 1.326gem -3, MoKa, 2=0.7107A, 12= 3.63 cm -1, F(000) = 520, T= 293 K, R = 0.037 for 1115 significant reflections. The second-harmonicgeneration (SHG) efficiency of this compound is only 1/10th of the urea standard. The observed low second-order nonlinear response may be attributed to the unfavourable packing of the molecules in the crystal lattice.

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Mr= 363.17, orthorhombic, P21212 ~, a= 5.251(4), b=14.962(5), c=19.112(5)A, U= 1501.41/k 3, Z=4, Dx=1.61Mgm -3, /t(CuKa)= 3.02 mm -1, 2(Cu Ka)= 1.5418/~, final R = 7.0% for 1091 reflections with Fo> 2e(Fo). The glycosidic torsion angle ZCN is 13"1 (12) °. The ribose has a C (3')-exo,C (4)-endo twist geometry. The dioxolane ring assumes an envelope conformation with 0(3') displaced by 0.453 (10)/k from the plane of the other four atoms. The conformation about the C(4')-C(5') bond is gauche-gauche. The structure is stabilized by two hydrogen bonds between screw-axis-related molecules. The crystal packing and the conformation of the molecule are very similar to those found in the structure of 2',3'-O-isopropylideneuridine which lacks the Br atom at the 5-position.

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C17H2602, M, = 262, triclinic, PI, a = 8.513(2), b = 8.970(2), c = 11.741(3)A, a = 120.51 (5), fl = 93.30(4), y = 68.43(4) ° , V = 708.9,/k 3, Z = 2, D O = 1.213, D e = 1.227 Mg m -a, g(Mo Ka, 2 = 0.7107 ,&) = 0.084 mm -1, F(000) = 288. The structure, solved by direct methods, has been refined to an R value of 5.9% using 1361 intensity measurements. The ring junctions, in sequence from either end of the polycycle, are cis, trans and cis.

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INTRODUCTION There is a paucity of research investigating the scar outcome of children with partial thickness burns. The aim of this study was to assess the scar outcome of children with partial thickness burns who received a silver dressing acutely. METHOD Children aged 0-15 years with an acute partial thickness burn, ≤10% TBSA were included. Children were originally recruited for an RCT investigating three dressings for partial thickness burns. Children were assessed at 3 and 6 months after re-epithelialization. 3D photographs were taken of the burn site, POSAS was completed and skin thickness was measured using ultrasound imaging. RESULTS Forty-three children returned for 3 and 6 month follow-ups or returned a photo. Days to re-epithelialization was a significant predictor of skin/scar quality at 3 and 6 months (p<0.01). Patient-rated color and observer-rated vascularity and pigmentation POSAS scores were comparable at 3 months (color vs. vascularity 0.88, p<0.001; color vs. pigmentation 0.64, p<0.001), but patients scored higher than the observer at 6 months (color vs. vascularity 0.57, p<0.05; color vs. pigmentation 0.15, p=0.60). Burn depth was significantly correlated with skin thickness (r=0.51, p<0.01). Hypopigmentation of the burn site was present in 25.8% of children who re-epithelialized in ≤2 weeks. CONCLUSION This study has provided information on outcomes for children with partial thickness burns and highlighted a need for further education of this population.

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The title compound, C29H20ClNOS, is a 1-substituted-3-phenylisoquinoline that crystallizes with four independent molecules in the asymmtric unit. The four molecules have similar C-S-C angles. The most noteworthy differences between the molecules relate to the inclination of the 3-phenyl subsituent with respect to the isoquinoline fused-ring [dihedral angles of 21.2 (1), 25.6 (2), 34.3 (1) and 36.5 (2)degrees].

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In the title compound, C18H11ClN2O2, the isatin and 2-chloro-3-methylquinoline units are both almost planar, with r.m.s.deviations of 0.0075 and 0.0086 angstrom, respectively, and the dihedral angle between the mean planes of the two units is 83.13 (7)degrees. In the crystal, a weak intermolecular C-H center dot center dot center dot O interaction links the molecules into chains along the c axis.