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Epilepsy is a highly prevalent and drug-refractory neurological disorder characterized by spontaneous recurrent seizures. Estrogen is identified to be proconvulsant and lowers the seizure threshold of female epilepsy. Estrogen receptor β (ERβ) has been proposed to mediate neuroprotection in epilepsy, although the underlying mechanism remains unknown. Rationale: In this study, we investigated the role of ERβ in the epileptogenesis of female temporal lobe epilepsy (TLE). Methods: Immunohistochemistry, immunofluorescence, western blots, Golgi staining, 1H MRS and whole-cell patch-clamp were used to evaluate ERβ expression, pathological changes, and synaptic excitation /inhibition (E/I) balance in female TLE patients and ovariectomized (OVX) chronic epileptic mice. Electroencephalogram (EEG) recordings were recorded to evaluate the epileptic susceptibility in OVX WT and ERβ-/- mice. And high-throughput RNA-sequence was performed to identify differential expression genes (DEGs) which can elucidate the potential mechanism of ERβ regulating the seizure susceptibility. Results: ERβ expression was decreased in the brains of female TLE patients and OVX chronic epileptic mice. ERβ deletion enhanced seizure susceptibility and exacerbated the imbalance of synaptic E/I in hippocampal CA1 area of OVX epileptic mice. In line with these observations, RNA-sequence data further identified glutamine ligase (GLUL) as the target of ERβ involved in regulating synaptic E/I in CA1. Furthermore, ERβ agonist WAY-200070 markedly suppressed epileptic phenotypes and normalized GLUL expression in CA1 region of kainic acid (KA) induced OVX chronic epileptic model. Conclusions: Our data provide novel insight into the pathogenesis of female TLE, and indicate ERβ provides a new therapeutic strategy for female TLE patients.

In this work, we present two new electron acceptors, TriPDI and Fused-TriPDI, in which three perylene diimide (PDI) moieties are tethered to a benzotrithiophene (BTT) core via either single bonds (TriPDI) or ring-fusion (Fused-TriPDI). TriPDI connects three PDIs to BTT via carbon–carbon single bonds, resulting in a rotatable and highly twisted skeleton. Instead, Fused-TriPDI, made through oxidative ring-fusion of TriPDI, exhibits good structural rigidity and planarity, as well as effective conjugation between PDI and BTT. As a result, the fused molecule shows up-shifted energy levels, and enhanced absorption and charge mobility over the unfused one. The polymer solar cells (PSCs) with a PTB7-Th:Fused-TriPDI blend show the best power conversion efficiency of 6.19%, which is around three times higher than that with PTB7-Th:TriPDI.

Exploring sustainable chemistry for renewable energy plays a key role in meeting the ever increasing energy demand without sacrificing the environment. In this study, two novel diketopyrrolopyrrol(DPP)-based π-conjugated oligomers (named as TPE-DPP4 and BP-DPP4) have been readily synthesized via a ligand-free Pd-catalyzed sequential activation of C H bond in two steps with good yields starting from simple building blocks. Poly(3-hexylthiophene) is employed as an electron donor to blend with the new DPP-derived electron acceptors for the fullerene-free bulk heterojunction organic photovoltaics. The power conversion efficiency of 2.49% has been achieved, corresponding with an open-circuit voltage of 1.16 V, which is among the highest open-circuit voltages for the single-junction organic photovoltaics. The facilely accessible electron acceptors blended with cost-effective poly(3-hexylthiophene) donor for fullerene-free organic photovoltaics opens a new pathway to access renewable solar energy via sustainable chemistry.

Toll-like receptors (TLRs) that mediate inflammatory responses play an important role in epilepsy; however, whether TLR1 is also involved in epileptogenesis remains unclear. Thus, in this study, we investigated the extent and pattern of TLR1 expression in epileptic tissues. One-hundred and thirty-two mice were intra-cerebroventricularly injected with PBS or kainic acid (KA) and were examined at 1, 3, 8 and 24 h. The expression pattern and distribution of TLR1 were examined by reverse-transcriptase polymerase chain reaction (RT-PCR), western blot analysis and immunohistochemistry staining. The mRNA and protein levels of TLR1 were significantly upregulated in the hippocampus and temporal cortex of epileptic mice compared with those of controls. TLR1 expression was increased as early as 1 h following KA treatment and peaked at 8 and 24 h. Immunohistochemistry staining demonstrated that TLR1 was distributed in the CA1-3, dentate gyrus and hilus regions of the hippocampus and different cortical regions. Immunofluorescent staining further revealed that TLR1 was primarily expressed in the neurons, microglia, and astrocytes of epileptogenic tissue. These results demonstrate that cortical and hippocampal sub-regional expression of TLR1 is altered during epileptogenesis in a time- and location-specific manner, suggesting a close association with the process of epilepsy.

A mononuclear vanadium complex, [VO2La] (1) (La = 4-chloro- 2-[(2-dimethylaminoethylimino)methyl]phenolate), and a binuclear vanadium complex, [VO2Lb]2 (2) (Lb = 2-[(2-aminoethyl imino)methyl]-4-bromophenolate), were prepared and characterized by physical chemical methods (IR and UV-Vis spectra, elemental analysis), and single crystal X-ray diffraction. The V coordinate center in (1) is ligated by three NNO donor atoms of the Schiff base ligand La, and two oxo groups, generating pyramidal coordination. Each V coordinate center in (2) is ligated by three NNO donor atoms of the Schiff base ligand Lb, and three oxo groups, generating octahedral coordination. Close examination on the relationship between structures of Schiff base ligands and the final complexes, hydrogen bonds are the substantial influence factors in the self-assembly processes.

Conjugated polymers are the primary blocks for organic electronics. Traditionally, conjugated polymers synthesized via Suzuki, Heck, and Stille couplings are catalyzed by soluble homogeneous ligated palladiums, which suffer the contaminations of residual nano-palladium and phosphine impurity resulting from side reaction of aryl–aryl exchange. To overcome these drawbacks, a commercially available, clean, and ligand-free heterogeneous catalyst Pd/C for the C–C coupling polymerizations was developed in this work. The Pd/C catalyst showed increases in catalytic activity for Suzuki and Heck polymerizations, as compared with the classical homogeneous catalyst Pd(PPh3)4. Furthermore, the Pd/C catalyst exhibited advantage of much less Pd residue in the resulting polymers, leading to better charge transport properties as demonstrated by field effect transistors.

Two new dioxovanadium complexes, [VO2L1]2 (1) and [VO2L2]2 (2), where L1 and L2 are the deprotonated forms of 2-bromo-4-chloro-6- { [2-(2-hydroxyethylamino)ethylimino)methyl]phenol (HL1) and 2- { [2-(2-hydroxyethylamino)ethylimino]methyl } phenol (HL2), respectively, have been synthesized and characterized by IR, UV-Vis spectra, and single-crystal X-ray diffraction. Both complexes are centrosymmetric dimeric dioxovanadium(V) compounds, with the V…V distances of 3.251(2) A and 3.127(2) A, respectively. The V atoms in the complexes are in octahedral coordination.

Two new oxovanadium complexes, [VOL1(acac)] (1) and [VO2L2]2 (2), where acac is acetylacetone, and L1 and L2 are the deprotonated forms of 2-bromo-4-chloro-6-[(2-dimethylaminoethylimino)methyl]phenol (HL1) and 2-bromo-4-chloro-6-[(2-methylaminoethylimino)methyl]phenol (HL2), respectively, have been synthesized and characterized by infrared (IR) spectra and single-crystal x-ray diffraction. Complex (1) is a mononuclear oxovanadium(IV) complex. Complex (2) is a centrosymmetric dinuclear dioxovanadium(V) complex, with the V···V distance of 3.133(2) A. The V atoms in both complexes are in octahedral coordination. The different of the structures of the complexes is largely induced by the hydrogen bonds during the self-assembly.

Two new dioxovanadium(V) complexes, [VO2L1]2 (1) and [VO2L2] (2), where L1 and L2 are the deprotonated forms of 4-chloro-2-[(2-isopropylaminoethylimino)methyl]phenol and 4-chloro-2-[(2-morpholin-4-ylethylimino)methyl]phenol, respectively, have been synthesized and characterized by IR spectra and single crystal X-ray diffraction. Complex (1) is a centrosymmetric dinuclear dioxovanadium complex, with the V atom six-coordinate in an octahedral geometry. The V⋅⋅⋅V distance is 3.224(2) A. Complex (2) is a mononuclear dioxovanadium complex, with the V atom five-coordinate in a distorted square pyramidal geometry. The steric effects of the terminal groups in the Schiff base ligands can influence the structures of the complexes.

Folded or nonfolded fluorophores incorporating naphthalene were synthesized and characterized by steady state fluorescence technique. Paraquat as an excellent quenching reagent quenched the fluorescence of Ne16 or nDs (n = 1–4) driven by charge transfer. Under aggregation of nDs, α-CD did not quench the fluorescence of 1D. At lower concentration, the quenching tendency of α-CD against nDs is 2D > 3D > 4D, while at higher concentration, the tendency is 2D

The dentate gyrus (DG) of the hippocampus is one of a few regions in the adult mammalian brain characterized by ongoing neurogenesis. Proliferation of neural precursors in the granule cell layer of the DG has been identified in pentylenetetrazol (PTZ) kindling epilepsy model, however, little is known about the molecular mechanism. We previously reported that the expression pattern of bone morphogenetic proteins-4 (BMP4) mRNA in the hippocampus was developmentally regulated and mainly localized in the DG of the adult. To explore the role of BMP4 in epileptic activity, we detected BMP4 expression in the DG during PTZ kindling process and explore its correlation with cell proliferation combined with bromodeoxyuridine (BrdU) labeling technique. We found that dynamic changes in BMP4 level and BrdU labeled cells dependent on the kindling stage of PTZ induced seizure-prone state. The number of BMP4 mRNA-positive cells and BrdU labeled cells reached the top level 1 day after PTZ kindled, then declined to base level 2 months later. Furthermore, there was a significant correlation between increased BMP4 mRNA expression and increased number of BrdU labeled cells. After effectively blocked expression of BMP4 with antisense oligodeoxynucleotides(ASODN), the BrdU labeled cells in the dentate gyrus subgranular zone(DG-SGZ) and hilus were significantly decreased 16d after the first PTZ injection and 1, 3, 7, 14d after kindled respectively. These findings suggest that increased proliferation in the DG of the hippocampus resulted from kindling epilepsy elicited by PTZ maybe be modulated by BMP4 over-expression.

A nonfullerene acceptor based on a 3D tetraperylene diimide is developed for bulk heterojunction organic photovoltaics. The disruption of perylene diimide planarity with a 3D framework suppresses the self-aggregation of perylene diimide and inhibits excimer formation. From planar monoperylene diimide to 3D tetraperylene diimide, a significant improvement of power conversion efficiency from 0.63% to 3.54% can be achieved.

Non-doped type white organic electroluminescent (EL) devices have the following structure ITO/m-MTDATA (30nm) /NPB (20-dnm) /rubrene (0.1nm) /NPB (dnm) /DPVBi (20nm) /TPBi (20nm) /Alq (10nm) /LiF/Al were fabricated. The EL spectrum of the devices are dependent on the d and when d=3, the CIE coordinates of the device were well within the white region for voltage raging from 3V to 15V. This device has a luminance of 18950cd/m2 at 15V and maximum power efficiency of 5.65cd/A at 6V.

A novel derivative of oligo(phenylenvinylene) (OPV), 2,5-diphenyl -1, 4-distyrylbenzene with two trans-double bonds (trans-DPDSB), is used as a blue emitting material in blue and white organic light-emitting devices (OLEDs). Blue devices with a configuration of indium-tin oxide (ITO)/N,N´-diphenyl-N,N´-bis(1-naphthyl)-(1,1´-biphenyl)-4,4´-diamine (NPB)/ trans-DPDSB / tris (8-hydroxyquinoline) aluminum (Alq3)/LiF/Al are constructed, where NPB, Alq3 and trans-DPDSB are used as hole-transporting, electron-transporting and light-emitting layers, respectively. The color of emission is changed from blue-green to pure blue when the trans-DPDSB layer is thicker. By inserting an ultrathin 5,6,11,12-tetraphenylnaphthacene (rubrene) yellow light-emitting layer between the Alq3 and trans-DPDSB layers, white OLEDs are obtained. The maximum efficiency and luminance of the blue and white devices are 1.2, 3.0 cd/A, and 1400, 7000 cd/m2, respectively.

In this paper, we describe the performance of an organic light emitting devices〔OLEDs〕 with ITO /4,4’,4“-tris{N,- （ 3-methylphenyl ） -N-phenylamino}triphenylamine (m-MTDATA) /N,N-diphenyl-N,N-bis1-naphthyl-1,1-biphenyl-4,4-diamine (NPB) /copper phthalocyanine (CuPc) / NPB / Bathocuproine(BCP) / tris-8-hydroxyquinoline Aluminum (Alq3) / LiF/ AL structure, the CuPc inserted between the two layers of NPB as a hole-consuming layer (HCL), and the BCP as a hole-blocking layer (HBL) . The EL spectrum peak is at 430 nm, indicating that the carrier recombination is confined in the NPB layer, in additional light emission originates from NPB. Compared with the luminous efficiency of the conventional diode without CuPc layer, that of the diode with HCL has been sharply increased up to 2.62 cd /A. It suggested that the CuPc and BCP exactly function as hole-consuming and hole-blocking layers, respectively, which enhance the efficiency of carrier，s recombination and confine the excitation in the EL layer.

We have fabricated an organic light-emitting devices with high efficiency and brightness utilizing thick layer of a starburst amine compound 4,4’, 4’’-tris{N,-(3-methylphenyl)-Nphenylamin} triphenylamine (m-MTDATA) as hole injection buffer layer. The brightness and the current efficiency were comparatively improved compared with those of the device without the buffer layer. The device with 10nm m-MTDATA act as buffer layer has max brightness was 18590cd/m2 at 17 V, and the highest luminous efficiency was achieved 4.30cd/A, at 7V, which is nearly three times than that of the device without it.

The dentate gyrus of the hippocampus is one of few regions in the adult mammalian brain characterized by ongoing neurogenesis. It has been demonstrated that Noggin antagonizes bone morphogenetic protein-4 (BMP4) to create a niche for subventricular zone neurogenesis. We previously demonstrated that Noggin and BMP4 showed strong expression in the proliferative subgranular layer of the dentate gyrus in adult rats. To examine the action of Noggin on cell proliferation in the dentate gyrus of adult rats, we administered antisense oligodeoxynucleotide (ASODN) to Noggin by continuous infusion into the lateral ventricle of rats. Antisense-infused rats displayed significant reduction in number of bromodeoxyuridine (BrdU) labeled cells in the dentate gyrus. This indicated that endogenous Noggin activity is important for naturally occurring cell proliferation in the dentate gyrus, and perhaps neurogenesis, and is one of the many factors involved in its regulation.

In this report, an atom efficient and facile synthetic strategy for accessing multi-diketopyrrolopyrrole (DPP)-based oligomers used in solution-processed organic field effect transistors (OFETs) and organic solar cells (OSCs) has been developed. The DPP units were successfully installed onto benzene and pyrene cores via palladium-catalyzed dehydrohalogenative coupling of mono-capped DPPs with multi-bromo-benzene or -pyrene (direct arylation), affording four oligomer small molecules (SMs 1-4) containing bis-, tri-, tri-, and tetra-DPP, respectively, in high yields of 78-96%. All the designed linear or branched DPP-based oligomers exhibit broad light absorptions, narrow band-gaps (1.60-1.73 eV), deep highest occupied molecular orbital (HOMO) levels (-5.26∼-5.18 eV), and good thermal stability (Td=390-401 °C). OFETs based on SMs 1-4 showed hole mobilities of 0.0033, 0.0056, 0.0005, and 0.0026 cm2 V(-1) s(-1), respectively. OSCs based on SMs 1-4 under one sun achieved power conversion efficiencies of 3.00%, 3.71%, 2.47%, and 1.86% accordingly, along with high open-circuit voltages of 0.86-0.94 V. For OSC devices of SM 1, SM 3, and SM 4, the solvent CHCl3 was solely employed to the formation of active layers; neither high boiling point additives nor annealing post-treatment was needed. Such a simple process benefits the large-scale production of OSCs via roll to roll technology.

In the hydrazone mol-ecule of the title compound, C(15)H(12)ClN(3)O(4)·H(2)O, the two benzene rings form a dihedral angle of 3.6 (1)°. In the crystal structure, the solvent water mol-ecules are involved in the formation of inter-molecular N-H⋯O and O-H⋯N hydrogen bonds, which link the mol-ecules into double ribbons extending along the b axis. Inter-molecular π-π inter-actions between the aromatic rings [centroid-centroid distances = 3.712 (3) and 3.672 (3) Å] link these ribbons further into layers parallel to the ab plane.

Two new dioxovanadium(V) complexes, [VO 2 L 1 ] ( 1 ) and [VO 2 L 2 ] 2 ( 2 ), where L 1 and L 2 are the deprotonated forms of 4-chloro-2-[(2-piperidin-1-ylethylimino)methyl]phenol and 2-ethoxy-6-[(2-ethylaminoethylimino)methyl]phenol, respectively, have been synthesized and characterized by i.r. spectra and single crystal X-ray diffraction. Complex ( 1 ) is a mononuclear dioxovanadium complex, with the V atom five-coordinate in a distorted square pyramidal geometry. Complex ( 2 ) is a dinuclear dioxovanadium complex, with the V atom six-coordinate in an octahedral geometry. The V∙∙∙V distance is 3.096(2) A. The hydrogen bonds among the Schiff base ligands can influence the structures of the vanadium complexes. Keywords: Synthesis; vanadium complex; Schiff base; X-ray structure analysis. INTRODUCTION A wide number of studies have focused on the Schiff bases and their metal complexes in the fields of coordination chemistry, biological chemistry, and material sciences. 1–4 In the past few decades, the vanadium complexes have been found to have interesting biological activities such as normalizing the high blood glucose levels and acting as models of haloperoxidases.

In the title compound, C15H13BrN2O4·CH4O, the two benzene rings form a dihedral angle of 3.2 (2)°. An intra­molecular O—H⋯N hydrogen bond is observed. In the crystal structure, mol­ecules are linked through O—H⋯O and N—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (10\overline{1}).

C16H17N3O2 ,m onoclinic, P21/n (no. 14), a =1 0.825(3) A, b =8 .916(2) A, c =1 5.310(2) A, / =1 06.291(2)°, V =1 418.3 A 3 , Z =4 , Rgt(F) =0 .0473, wRref(F 2 ) =0 .1344, T =2 98 K. Source of material Th ec ompoun dw as prepared by the condensation reaction of 3hydroxy benzaldehyde (1 mm ol, 0.122 g) and 4dimethylaminobenzohydrazide (1 mmol, 0.179 g) in anhydrous methanol (30 ml )a ta mbient temperature. Colourless blockshaped single crystals suitable for X-ray structural determination were obtained by slow evaporation of the solution for aw eek. Experimental details H(2) wa sl ocated from ad ifferenc eF ourier ma pa nd refined isotropically, with the N–H distance restrained to 0.90(1) A. The remaining Ha tom sw ere positioned geometrically and constrained to ride on their parent atoms, with C–H distances of 0.930.96 A, O–H distance of 0.82 A, and with Uiso(H) =1 .2Ueq(C) and 1.5Ueq (O1 and Cmethyl). Discussion Considerable attention has been focused on hydrazones and their medicinal applications [1-5] .T he study of the crystal structures of such compounds is of particular interest [6-8]. As ac ontinuation of our work on such compounds, we report herein the crystal structure of the title hydrazone derivative. The molecular structure of the title compound is shown in the figure. The dihedral an

C21H21N3O2 ,m onoclinic, P21/c (no. 14), a =5 .0165(5) A, b =1 3.148(1) A, c =2 6.705(2) A, / =9 0.198(1)°, V =1 761.4 A 3 , Z =4 , Rgt(F) =0 .0656, wRref(F 2 ) =0 .1768, T =2 98 K. Source of material Th ec ompoun dw as prepared by the condensation reaction of 2methoxy-1-naphthaldehyde (1mmol, 0.186 g) and 4dimethylaminobenzohydrazide (1mmol, 0.179 g) in anhydrous methanol (30 ml )a ta mbient temperature. Colourless blockshaped single crystals suitable for X-ray structural determination were obtained by slow evaporation of the solution for aw eek. Experimental details H(2) wa sl ocated from ad ifferenc eF ourier ma pa nd refined isotropically, with the N–H distance restrained to 0.90(1) A. The remaining Ha tom sw ere positioned geometrically and constrained to ride on their parent atoms, with C–H distances of 0.930.96 A, and with Uiso(H) =1 .2Ueq(C) and 1.5Ueq(Cmethyl).

A diketo-pyrrolo-pyrrole (DPP) oligomer containing three DPP cores (Ph4Th4(DPP)3) was synthesized via direct arylation of C-H bonds (DACH). Ph4Th4(DPP)3 has good solubility in many organic solvents, and shows a broad absorption band from the visible to near-infrared region as well as a field-effect hole mobility as high as 0.006 cm(2) V(-1) s(-1). Solution-processed bulk heterojunction organic solar cells based on blends of Ph4Th4(DPP)3 as electron donor and fullerene derivative as electron acceptor were fabricated. An optimized power conversion efficiency of 3.76% with a high open-circuit voltage of 0.85 V was achieved after finely tuning the morphology by changing the blend ratio and by adding additives. These results indicate that DACH is an effective way to produce π-conjugated oligomers for organic solar cells.

Diketopyrrolopyrrole (DPP) derivatives are an important class of high-performance pigment used in inks, paints, plastics, and organic electronics. Until now, DPP derivatives containing sophisticated aryl units at the DPP core have usually been obtained via Suzuki, Stille, or Negishi cross-coupling reactions, which require organometallic precursors. In this work, a series of DPP-based π-conjugated molecules bearing diverse aryl substituents on the thiophene- or benzene-DPPs were facilely synthesized in moderate to excellent yields through the Pd-catalyzed direct arylation of C–H bonds. The synthetic procedures feature advantages over traditional C–C cross-coupling reactions such as: (1) avoidance of the use of organometallic reagents in the starting materials leading to simpler byproducts and higher atom economy, (2) fewer synthetic steps, (3) higher yields, (4) better compatibility with chemically sensitive functional groups, and (5) simpler catalytic systems free of phosphine ligands. These advantages make the present protocol an ideal and versatile strategy for the synthesis of DPP derivatives, especially for structurally complicated DPPs that may possess chemically sensitive functionalities. The optical and electrochemical properties of the synthesized DPPs (17 compounds) were systematically investigated using UV-vis spectroscopy, steady-state fluorescence spectroscopy, and cyclic voltammetry (CV).

A graded doping technique was introduced to fabricate high brightness and high efficiency OLEDs, in which the luminescent layer consists of the mixture of NPB, Alq3 and an emitting dopant 5,6,11,12-petraphenylnaphthacene (Rubrene), where the concentration of NPB raised while the concentration of Alq 3 was declined gradually in the deposition process. This graded doping device exhibited the maximum emission of 49300cd/m 2 at 35V and the maximum efficiency of about 8cd/A at 10V, respectively, which have been improved by two times in comparison with the conventional doped devices.

In the title compound, C15H13FN2O, the dihedral angle between the benzene rings is 16.9 (2)°. The F atom and the O atom are in a syn conformation. In the crystal, molecules are linked by N—H...O hydrogen bonds to generate C(4) chains propagating along the b-axis direction.

In the title compound, C15H13N3O3, the dihedral angle between the benzene rings is 1.01 (3)° and that between the nitro group and its attached ring is 5.99 (15)°. In the crystal, molecules are linked by N—H...O hydrogen bonds generating C(4) chains along [010].

In the mol-ecule of the title compound, C(17)H(13)N(3)O(2), the naphthyl ring system and the pyridine ring form a dihedral angle of 12.2 (3)°. An intra-molecular O-H⋯N hydrogen bond generates a six-membered ring with an S(6) ring motif. This also contributes to the relative overall near planarity of the mol-ecule [r.m.s. deviation of all 22 non-H atoms = 0.107 (5) Å]. In the crystal, mol-ecules are linked through inter-molecular N-H⋯N hydrogen bonds, forming chains along the a axis.

In the title compound, C(19)H(16)N(2)O(2), the benzene ring and the naphthyl ring system form a dihedral angle of 8.7 (3)° and an intra-molecular O-H⋯N hydrogen bond generates an S(6) ring. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming C(4) chains propagating in [001].

In the title compound, C(19)H(16)N(2)O(2), the benzene ring and naphthyl ring system are inclined at a dihedral angle of 16.1 (3)°. An intra-molecular O-H⋯N hydrogen bond influences the mol-ecular conformation. In the crystal, mol-ecules are linked through N-H⋯O hydrogen bonds into chains running along the a axis.

In the title compound, C(15)H(13)BrN(2)O(3), the two benzene rings form a dihedral angle of 16.9 (2)°. An intra-molecular O-H⋯N hydrogen bond affects the mol-ecular conformation. In the crystal structure, mol-ecules are linked through N-H⋯O hydrogen bonds into chains running along the a axis.

In the title compound, C(14)H(11)N(3)O(4), the two benzene rings form a dihedral angle of 45.3 (3)°. The nitro group is twisted out of the attached ring by a dihedral angle of 37.5 (3)°. In the crystal structure, mol-ecules are linked into a two-dimensional network parallel to (100) by O-H⋯O and N-H⋯O hydrogen bonds.

In the title compound, C(17)H(19)N(3)O(2), the two benzene rings form a dihedral angle of 89.2 (2)°. In the crystal structure, mol-ecules are linked through N-H⋯O hydrogen bonds, forming C(4) chains running along the c axis.