RESUMEN
An exceptionally simple amide-imine conjugate, (E)-N'-(4-(diethylamino)-2-hydroxybenzylidene)-4-methylbenzohydrazide (L), derived by the condensation of 4-methyl-benzoic acid hydrazide (PTA) with 4-(diethylamino)-2-hydroxybenzaldehyde was utilized to prepare a dimeric oxo-vanadium (V1) and a one-dimensional (1D) copper(ii) coordination polymer (C1). The structures of L, V1 and C1 were confirmed by single crystal X-ray diffraction analysis. The experimental results indicate that V1 is a promising green catalyst for the oxidation of sulfide, whereas C1 has potential for a C-S cross-coupling reaction in a greener way. Most importantly, C1 is an efficient 'turn-on' fluorescence sensor for bilirubin that functions via a ligand displacement approach. The displacement equilibrium constant is 7.78 × 105 M-1. The detection limit for bilirubin is 1.15 nM in aqueous chloroform (chloroform/water, 1/4, v/v, PBS buffer, and pH 8.0).
RESUMEN
Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a rare form of idiopathic interstitial pneumonia. The disease is characterized by fibrosis of the pleura and subpleural lung parenchyma predominantly affecting the upper lobes. Various triggers have been proposed as inciting factors in the development of the disease. Diagnosis is made clinically in conjunction with radiographic findings and histopathology when available. There are no known effective treatment options and several cases of lung transplantation have been reported. We report a case of an 86-year-old female who presented to the emergency department with worsening dyspnea and hypoxia. She had a history of unexplained pneumomediastinum and a 20 - 25 pounds unintentional weight loss over 10 months. Computed tomography (CT) of the chest without contrast revealed radiographic evidence of IPPFE. Despite symptomatic management with antibiotics, diuretics, and steroids, her condition continued to deteriorate. Unfortunately, our patient was not a candidate for a lung transplant. She was transitioned to hospice care and succumbed to her disease. IPPFE is a rare disease with an unknown prevalence. It has a median survival rate of 2 years. Usually, there is an overlap with interstitial lung diseases, making it challenging to diagnose. There are only a few cases reported in the literature, and there are currently no guidelines available on the appropriate management of this debilitating disease. We recommend more cases be reported, and further research is done to establish better criteria for diagnosis and management.
RESUMEN
A dinuclear Fe(iii) complex (F1) of an imine derivative (L1) derived from 3-ethoxy-2-hydroxy-benzaldehyde and hydrazine, structurally characterised via single crystal X-ray studies, is employed for the catalytic conversion of epoxides to cyclic carbonates utilizing carbon dioxide. In addition, F1 is employed for the selective optical recognition of nano-molar levels of Zn2+ (42.23 nM) via a metal displacement approach. The Job plot reveals interactions between F1 and Zn2+ at a 1 : 3 molar ratio with an association constant of 7.71 × 104 M-1. Studies on the catecholase-like activity of F1 reveal a k cat value of 4.42 × 103 h-1.
RESUMEN
Three new amide-imine conjugates, namely [(E)-2-hydroxy-N'-((2-hydroxynaphthalen-1-yl)methylene)benzohydrazide] (SALNP), [(E)-N'-(4-(diethylamino)-2-hydroxybenzylidene)-2-hydroxybenzohydrazide] (SALSD), and [(E)-N'-(3-ethoxy-4-hydroxybenzylidene)-2-hydroxybenzohydrazide] (SALVN), derived by reacting 2-hydroxybenzohydrazide (SAL) with three different aldehyde, 2-hydroxynapthaldehyde, 4-(diethylamino)-2-hydroxybenzaldehyde, and 3-ethoxy-4-hydroxybenzaldehyde, respectively. Three mononuclear oxovanadium(V) and two µoxo-bridged dinuclear molybdenum(VI) complexes have been synthesized using SALNP and SALSD. Besides, SALVN is used to prepare oxovanadium(V) and dioxomolybdenum(VI) complexes. All five metal complexes along with three amide-imine conjugates are characterized by single crystal XRD analysis. Some of them have been explored as catalyst for oxidation of alkyl benzene and styrene. Antitumor activities of the metal complexes along with ligands have been studied on Dalton lymphoma (DL) and 2PK3 murine lymphoma cells.
RESUMEN
We have successfully embedded rhombohedral crystallites of silver nanoparticles (Ag-NPs) over mesoporous alumina (Ag@Al2O3) material for the first time. The Ag@Al2O3 has been characterized by powder X-ray diffraction (PXRD), ultra high resolution transmission electron microscopy (UHR-TEM), scanning electron microscopy (SEM), N2 adsorption/desorption isotherm, Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible absorption spectra (UV-Vis), and thermogravimetric analysis (TGA). The PXRD confirms the presence of the rhombohedral phase of Ag nanoparticles. The agglomeration of the silver nanoparticle having a dimension of 80-90nmhas been clearly observed from UHR-TEM images. This novel nanocatalyst showed excellent catalytic activity towards the N-alkylation of hetero (aromatic) amines and aromatic amines using alcohols as the alkylating agent. The catalyst is heterogeneous in nature and can be recovered and recycled more than five reaction cycles without any noticeable loss in its catalytic activity.
RESUMEN
We have synthesized Ag@polypyrrole nanomaterial by dispersing ultrafine silver nanoparticles (Ag NPs) over the organic polymer polypyrrole. The Ag@polypyrrole material has been characterized by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), Fourier transform infrared (FT-IR), ultraviolet-visible absorption (UV-vis) and atomic adsorption spectroscopy (AAS), and thermogravimetric analysis (TGA). The XRD pattern suggested the cubic crystalline phase of Ag NPs in Ag@polypyrrole. TEM image analysis revealed that silver nanoparticles are highly dispersed in the polymer matrix. The Ag@polypyrrole acts as an efficient and versatile heterogeneous nanocatalyst in the N-alkylation of amines using alcohols. The catalyst can be easily prepared, highly robust and reused several times without decrease in its catalytic activity.
RESUMEN
A graphene based composite with gold nanoparticles has been synthesized via a simple chemical route and the structure and compositions of nanocomposite has been characterized. The catalyst was found to be remarkably stable and active for the oxidative esterification of alcohols under present reaction conditions using molecular oxygen as green oxidant and Suzuki cross-coupling reactions between aryl halides and phenylboronic acids using environmentally friendly water as solvent. The versatility of both the protocols was demonstrated by taking a number of substrates. This protocol offers several advantages like high yields, clean reactions, recyclability of the catalyst, reaction in water and use of green oxidant. This study suggests graphene, as an economical substitute for carbon nanotubes, could act as a prominent support in heterogeneous catalysis.
RESUMEN
A new ruthenium-grafted mesoporous organic polymer Ru-MPTAT-1 has been synthesized via simple and facile in situ radical polymerization of 2,4,6-triallyloxy-1,3,5-triazine (TAT) in aqueous medium in the presence of an anionic surfactant (sodium dodecyl sulfate) as a template, followed by grafting of Ru(II) onto its surface. Ru-MPTAT-1 has been characterized by elemental analysis, powder XRD, HRTEM, FT-IR, UV-vis DRS, TG-DTA, FESEM and XPS characterization tools. The Ru-MPTAT-1 material showed very good catalytic activity in the Suzuki-Miyaura cross-coupling reaction for aryl halides and transfer hydrogenation reaction for a series of carbonyl compounds. The catalyst is easily recoverable from the reaction mixture and can be reused several times without appreciable loss of catalytic activity in the above reactions. Highly dispersed and strongly bound Ru(II) sites at the mesoporous polymer surface could be responsible for the observed high activity of the Ru-MPTAT-1 catalyst in these reactions.
RESUMEN
Furfural-imine functionalized mesoporous organosilica material has been synthesized by post-synthesis surface functionalization of 2D-hexagnoal mesoporous SBA-15 with organosilane precursor 3-aminopropyltriethoxy-silane (APTES) followed by Schiff-base condensation with furfural. On the other hand, furfural-imine functionalized MCM-41 has been synthesized by Schiff-base condensation of furfural and 3-aminopropyltriethoxy-silane (APTES) followed by its hydrothermal co-condensation with tetraethylorthosilicate (TEOS) in the presence of a cationic surfactant CTAB. Subsequent reaction of the imine-functionalized mesoporous organosilicas with Cu(OAc)2 in absolute ethanol produced Cu(II)-grafted mesoporous nanocatalysts 1 and 2, respectively. Powder XRD, HR TEM, FE SEM, N2 sorption and EPR experimental tolls are employed to characterize these Cu-grafted furfural-imine functionalized nanocatalysts. Cu-grafted MCM-41 (1) showed very good catalytic efficiency for the coupling of aryl bromides and thiophenol under aerobic conditions to produce different thioethers. On the other hand, Cu-anchored mesoporous SBA-15 nanocatalyst (2) exhibited high catalytic activity for one-pot three component coupling of different aryl halides with thiourea and benzyl bromide in aqueous medium to produce different aryl alkyl thioethers in very good yields. Both Cu-grafted mesoporous nanocatalysts can be efficiently reused for several reaction cycles.
