15017-21-7

A colorimetric and fluorescent chemosensor (L) for Al(III) was synthesized and fully characterized. L could be both used as a colorimetric and fluorescent chemosensor for the detection of Al3 + ions with low detection limit (8.87 × 10- 7/

A fluorescent probe based on benzoyl hydrazine was synthesized and characterized as an Al3+-selective fluorescent probe. This probe showed good selectivity towards Al3+ compared to other common ions. Under optimized experimental cond

A tridentate Schiff base ligand (E)-N′-((2-hydroxynaphthalen-1-yl)methylene)benzohydrazide (H2L) and its oxido-vanadium(v) complexes with formulae [VO(L)(MeOH)(OMe)] (1), [VO(L)(OEt)] (2), and [VO(L)(OPr)] (3) have been synthesized and fully ch

We synthesized and validated five Schiff base Pt(II) complexes derived from 2-hydroxy-1-naphthaldehyde benzoyl hydrazone and its derivatives, which are modified at the benzohydrazide structures (L1–L5). The complexes were [Pt(L1)(DMSO)Cl] (C1), [Pt(L2)(DM

The reimagined concept of long-range tautomeric proton transfer using crane subunits is shown by designing and synthesising two new acylhydrazones containing a 7-hydroxyquinoline (7-OHQ) platform. The acylhydrazone subunits attached to the 7-OHQ at the 8t

Metal ions play an important role in the pathogenesis of Alzheimer's disease (AD). Metal dyshomeostasis, β-amyloid (Aβ) accumulation and oxidative stress, etc. are related to metal ions. So, metal therapeutics has aroused increasingly more attention, espe

We report the synthesis of a vanadium(V) complex characterized by FT-IR and 1H NMR spectroscopy. The structure of the complex was established by single crystal X-ray crystallography. We also carried out the catalytic oxidation of benzyl alcohol, hetero-aryl alcohols and propargylic alcohols. Tandem synthesis of oximes from alcohols were also carried out using our vanadium(V) complex. The newly synthesized complex acts as a catalyst for oxidation reactions and tandem synthesis of oxime from alcohols.

Three new complexes of nickel(II), having general formula [Ni(L1)(PPh3)] (1), [Ni(L1)(4-picoline)] (2), and [Ni(L2)(4-picoline)] (3) were synthesized by the reaction of Ni(OAc)2·4H2O with corresponding benzolyhydrazine-derived Schiff base ligands i.e. [4-(diethylamino)-2-hydroxybenzylidene]-benzohydrazonic acid (H2L1) or [2-(hydroxynaphthalen-1-yl)methylene]-benzohydrazonic acid (H2L2) and PPh3/4-picoline as co-ligand in 1:1:1 ratio in methanol. All the three complexes were air-stable, isolated as reddish brown solids and characterized by Elemental analysis, FT-IR, 1H, 13C{1H}, 31P{1H} NMR spectroscopy and mass spectrometry. The structures of all three complexes were determined by single crystal X-ray diffraction studies which revealed the distorted square planar geometry of the complexes. In these complexes, three coordination sites were occupied by ONO pincer type Schiff base ligand and the fourth site was blocked by phosphorus (P) or nitrogen (N) atom of the co-ligand. The catalytic potential of all three complexes was explored in the synthesis of a series of 2-arylbenzoxazoles from aldehydes and 2-aminophenol, using low catalyst loading (0.5 mol%). Complex 1 was found to be the best catalyst among three complexes, for the synthesis of a series of 2-aryl benzoxazoles. The ease of synthesis, air-stability and robustness of the catalyst, and good TONs are some of the key characteristics of the described catalytic system.

An efficient and BF3·Et2O-catalyzed chemoselective synthesis of diversified 1,3-diarylisobenzofuran in a high yield has been described. The reaction proceeds through sequential hydroarylation-cyclization between 2-formylarylketones and electron-rich arenes/heteroarenes. Advantageous features of the developed methodology include operational simplicity, a broad substrate scope, and applicability towards gram scale synthesis. The utility of isobenzofuran derivatives as the diene was extended to the synthesis of [4+2] cyclo-adducts with DMAD and the synthesis of 1,2-dicarbonylarenes in good yields.

An efficient and base-mediated one-pot regiospecific synthesis of structurally diversified isoquinolines and benzo[h] isoquinolines from easily accessible ortho-formyl-arylketones and aryl/(het)arylmethanamines has been described. Challenging 3-alkynyl/alkenyl isoquinolines and bis-isoquinolines were easily attained through this developed chemistry, which can be further used for various organic transformations. Operational simplicity, high atom-economy, broad substrate scope, functional group tolerance and applicability towards large scale synthesis are the advantageous features of this developed methodology.

The simpler, the better! A series of simple and highly fluorescent salicylaldehyde hydrazide molecules (41 samples) have been designed and prepared. Even though these soft materials contain a very small π-conjugated system, they can go through multiple intramolecular and intermolecular hydrogen bonds promoted excited-state intramolecular proton-transfer (ESIPT) to display strong blue, green, yellow, and orange aggregation-induced emission (AIE) with large Stokes shifts (up to 184 nm) and high fluorescence quantum yields (Ф up to 0.20). Unusual mechanochromic fluorescence enhancements are also found in some solid samples. Through coordination, hydrogen and halogen bonds, these flexible molecules can be used as Mg2+ (Ф up to 0.46) probes, universal anion (Ф up to 0.14) and unprotected amino acids (Ф up to 0.16) probes, and chiral diamine (enantiomeric selectivity and Ф up to 0.36 and 0.062, respectively) receptors. Combining their advantages of AIE and biocompatibility, these low cytotoxic dyes have potential application in living cell imaging. Furthermore, the effects of different functional groups on the molecule arrangement, ESIPT, AIE, probe, and chiral recognition properties are also examined, which provide a simple and bright paradigm for the design of multiple-stimuli-responsive smart materials.

Background: The field of coordination chemistry has registered a phenomenal growth during the last few decades. It is well known that precious metals have been used for medicinal purposes for at least 3500 years. At that time, precious metals were believed to benefit health because of their rarity, but research has now well established the link between medicinal properties of inorganic drugs and specific biological properties. Methods: The current study was designed to explain the synthesis and characterization of the lanthanide (III) nitrate complexes with N-(2-hydroxynaphthalen-1-yl) methylene) nicotinohydrazide schiff base and to evaluate the antibacterial and the antioxidant activities of the schiff base and it's lanthanide ion complexes. Antimicrobial activity of the Lanthanide (III) nitrate complexes with N-(2-hydroxynaphthalen-1-yl) methylene) nicotinohydrazide schiff base was estimated by minimum inhibitory concentration (MIC, μg/mL) using a micro-broth dilution method for different clinical isolates such as Eschereshia coli and Enterococcus faecalis. The antioxidant activities of the ligand and its lanthanide complexes were tested using a UV-Visible spectrophotometer by preparing 5×10-4 M of all tested samples and DPPH in Dimethyl sulphoxide (DMSO). Results: Our present study has shown that moderate antimicrobial activity exists against both ligand and its complexes. There was no significant difference between Gram-positive and Gram-negative bacteria towards the tested ligand and its complexes. The free ligand has scavenging activity between 13-21 % while all complexes are more efficient in quenching DPPH than free ligand. Conclusion: The results obtained herein indicate that the ligand and its complexes have a considerable antibacterial activity as well as antioxidant activity in quenching DPPH.

Pd(II) complexes appended with ONO pincer type ligand were synthesized, structurally characterized and successfully applied as catalysts for regieoselective C?2 arylation of 2-oxindole via in situ C (sp2)?OH activation in aqueous-organic media

An easy and convenient synthesis of a new series of octahedral ruthenium(III) complexes bearing benzoylhydrazone of general formula [Ru(L)Cl(PPh3)2] (where L = 2-hydroxy-1-naphthaldehyde benzoylhydrazone) has been reported. The composition of all the complexes has been unequivocally characterized by microanalysis, IR, electronic, magnetic and EPR spectroscopic techniques. The substituted benzoylhydrazone ligands behave as a dianionic tridentate O, N and O donors and coordinate to ruthenium via the phenolic oxygen, the azomethine nitrogen and the deprotonated amide oxygen. The complexes exhibit moderately strong ligand-to-metal charge transfer transitions in the visible region and intraligand transition in the UV region. Magnetic moment of the complexes (298 K) lies in the range 1.72-1.97 μB reveals the presence of one unpaired electron in the metal centre. The low spin mononuclear Ru(III) benzoylhydrazone complexes display rhombic EPR spectral pattern in frozen solution. The molecular structure of two of the complexes has been established by single crystal X-ray crystallography and indicates the presence of a distorted octahedral geometry in these complexes. Further, the complexes 1-5 have been proven to catalyse the transfer hydrogenation of linear, cyclic and aromatic ketones to their corresponding secondary alcohols in the presence of i-PrOH/KOH at 82 °C and the maximum conversion is up to 99%. The effect of other variables on the transfer hydrogenation reaction such as solvent, base, temperature, time and catalyst loading is also reported.

Convenient synthesis of eight new octahedral ruthenium(II) carbonyl benzoylhydrazone complexes having the general molecular formula [Ru(L)(CO)(EPh3)2] (where E = P or As; H2L = benzoylhydrazone ligand, the two H's representing the two dissociable protons) has been described. The substituted benzoylhydrazone ligands behave as a dianionic tridentate O, N and O donors (L) and coordinates to ruthenium via the phenolate oxygen, the azomethine nitrogen and the deprotonated amide oxygen. The compositions of the complexes have been established by elemental analysis and spectral methods (FT-IR, 1H NMR, 13C NMR, UV-vis). The crystal structure of one of the complexes, [Ru(L2)(CO)(PPh3) 2] (2), has been solved by single crystal X-ray crystallography and it indicates the presence of a distorted octahedral geometry in these complexes. All the complexes exhibit metal-to-ligand charge transfer (MLCT) transitions in the visible region and display one quasi-reversible reduction and two irreversible oxidations. Further, the catalytic efficiency of the complexes has been investigated in the case of transfer hydrogenation of ketones to the corresponding secondary alcohols. The influence of base, reaction temperature and catalyst loading in transfer hydrogenation reaction was also evaluated. The complexes were found to be efficient catalysts with conversion up to 99.5% in presence of iso-propanol/KOH.

The present invention relates to the use of mixtures containing hydrazone compounds and copper for controlling the growth of fungi.

Fourteen acylhydrazides have been condensed with three aromatic o-hydroxy aldehydes (pyridoxal, salicylaldehyde, and 2-hydroxy-1-naphthaldehyde) to give 42 acylhydrazones, of which 38 are new.These compounds complex iron and have shown varying abilities to promote the movement of iron across biological membranes.Their infrared and nuclear magnetic resonance spectra support the structures assigned to them.

Lanthanum(III), cerium(III), praseodymium(III), neodymium(III), samarium(III), gadolinium(III), terbium(III), dysprosium(III) and yttrium(III) complexes of salicylaldehyde benzoyl hydrazone (H2L), salicylaldehyde 2-picoloyl hydrazone (H2L'), and of o-hydr

Magnesium(II), zinc(II), cadmium(II), mercury(II) and lead(II) complexes of (substituted) salicylidene-benzoyl hydrazide, salicylidene-2-picoloyl hydrazide, salicylidene-2-quinoloyl hydrazide and salicylidene-8-quinoloyl hydrazide schiff bases have been s

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