Search results for "Azone"
showing 10 items of 170 documents
Competitive NH···Ru/Fe Hydrogen Bonding in Ferrocenyl Ruthenocenyl Tosyl Hydrazone
2016
A strong nonclassical NH···Fe intramolecular hydrogen bond (IHB) is present in the literature-known diferrocenyl tosyl hydrazone (1). Here, we confirm by NMR and IR spectroscopy as well as by XRD methods that an analogous NH···Ru IHB is present in the heavier homologue diruthenocenyl tosyl hydrazone (2). The NH···Ru IHB in 2 is stronger than the NH···Fe IHB in 1 by 6 kJ mol–1, as determined by IR spectroscopy. Further, we probed the E/Z isomer directing abilities of NH···M IHBs in the synthesis of the mixed metallocenyl compound ferrocenyl ruthenocenyl tosyl hydrazone (3). 3 is obtained as a mixture of the Z and E isomers (3a,b) with NH···Ru and NH···Fe IHBs, respectively. At 111 °C, 3a is …
4-(2-Adamantyl)thiosemicarbazone
1984
Aus der Umsetzung von 4-(2-Adamantyl)thiosemicarbazid (1) mit den Carbonylverbindungen 2a-d gehen die 4-(2-Adamantyl)thiosemicarbazone 3a-d hervor. Die Startkomponente 1 ist aus 2-Aminoadamantan (4) uber das (2-Adamantyl)-isothiocyanat (5) zuganglich. Verbindung 5 und Vertreter des Strukturtyps 3 vermogen antivirale, antimykotische und antipyretische Wirkung auszuuben. Antiviral Agents, XXIV: 4-(2-Adamantyl)thiosemicarbazones Reactions of 4-(2-adamantyl)thiosemicarbazide (1) with the carbonyl compounds 2a-d yield the 4-(2-adamantyl)thiosemicarbazones 3a-d. The starting material 1 is accessible from 2-aminoadamantane (4) via 2-adamantyl isothiocyanate (5). Compound 5 and representatives of t…
ChemInform Abstract: Synthesis and Pharmacological Evaluation of 1-Methyl-5- [substituted-4(3H)-oxo-1,2,3-benzotriazin-3-yl]-1H-pyrazole-4-acetic Aci…
2010
Abstract Several new 1-methyl-5-[substituted-4-oxo-1,2,3-benzotriazin-3-yl]-1H-pyrazole-4-acetic acids and their ethyl ester derivatives were prepared. The compounds were tested for analgesic and antiinflammatory activities, acute toxicity, ulcerogenic effect, and as in vitro inhibitors of 3α-hydroxysteroid dehydrogenase (3α-HSD), since it is claimed that the inhibition of such an enzyme predicts in vivo antiinflammatory activity. Some compounds were more active than phenylbutazone in the phenylbenzoquinone and acetic acid peritonitis tests, and equiactive to the same drug in the carrageenin paw edema test. All the compounds inhibited the 3α-HSD, but no correlation was observed with the paw…
Predominance of 2-arylhydrazones of 1,3-diphenylpropane-1,2,3-trione over its proton-transfer products
2001
2-Phenylhydrazones of 1,3-diphenyl-1,2,3-trione are the dominant tautomeric form detected in chloroform solution by 15N NMR chemical shifts. The substituent in the phenylhydrazone moiety does not affect this tautomeric preference. The substituent effect is transmitted effectively only to the hydrazone nitrogen and hydrogen atoms. Ab initio calculations show that the ketohydrazone tautomer is really very much favoured over its proton-transfer products in chloroform solution. The same tautomer was also detected in the crystal state by X-ray crystallography. Copyright © 2001 John Wiley & Sons, Ltd.
ChemInform Abstract: Gold(I)-Catalyzed Intermolecular Cycloaddition of Allenamides with α,β-Unsaturated Hydrazones: Efficient Access to Highly Substi…
2015
α,β-Unsaturated N,N-dialkyl hydrazones undergo a mild [2 + 2] cycloaddition to allenamides when treated with a suitable gold catalyst. The method, which represents the first application of N,N-dialkyl hydrazones in gold catalysis, is compatible with a wide variety of substituents at the alkenyl moiety of the hydrazone component, proceeds with excellent levels of regio- and diastereoselectivity, and provides densely substituted cyclobutanes with good to excellent yields.
Method for determination of formaldehyde in air in the pptv-range by HPLC after extraction as 2,4-dinitrophenyl-hydrazone
1982
The derivatization of formaldehyde with 2,4-dinitrophenylhydrazine and the extraction of the product formalhydrazone is studied. The determination is carried out by HPLC. Applying a cryogenic sampling technique and a sampling volume of 300l of air the detection limit of formaldehyde in air is 30 pptv and this is suitable for measurements of formaldehyde in the atmosphere. (IFU)
A wide family of pyridoxal thiosemicarbazone ferric complexes: Syntheses, structures and magnetic properties
2009
Abstract This study reports the syntheses and the characterization of 12 ferric complexes of pyridoxal thiosemicarbazone. The richness of the coordination chemistry of this ligand is highlighted by the modulation of its charge from neutral H 2 L to anionic L 2− , thus leading to a wide family of ferric compounds with charge varying from +3 to −1. The structures of complexes [Fe(HL) 2 ]ClO 4 · 2H 2 O and [Fe(HL)L] · 4.5H 2 O were solved and discussed with a particular attention brought to the intermolecular interactions occurring between the complexes. The investigation of magnetic properties of these compounds revealed that two of them are in the HS state at any temperature, whereas the ot…
Diferrocenyl tosyl hydrazone with an ultrastrong NHFe hydrogen bond as double click switch.
2014
The intramolecular NH⋯Fe hydrogen bond in diferrocenyl hydrazone 2 raises the barrier for intramolecular electron transfer in its mixed-valent cation 2+ and is only disrupted by double oxidation to 22+.
The synthesis of thienocycloheptenoindoles
1984
A synthesis of the methylthieno[3,2-c]cyclohepteno[b]indole 7 from 2-methylthieno[3,2-b]cycloheptanone 3 is described. Unsuccessful attempts to prepare the isomeric thienocycloheptenoindole system present in formula 2, from the dihydrobenzothiophenone 8, and from derivatives of 5-(2-thienyl)-4-oxopentanoic acid, 17 and 18, and from N-benzylcycloheptindol-1-one 22 were unsuccessful. The preparation of 4,5-dihydro-2-phenyl-1-thienylmethyl-3H-pyridazin-3-one 20 and of the 5-aminopyrazole 21 are reported.
A novel mixed valent Cu(II)-Cu(I) 2D framework made of a hydrazone and μ-SCN bridged metallacyclic loops cross-linked by μ3-SCN chains.
2012
A mixed valent copper complex [Cu(II)Cu(I)(L)(μ-SCN)(μ(3)-SCN)](n) (LH = N'-((pyridin-2-yl)methylene)acetohydrazide) has been synthesized and characterized. It is a unique example of a 2D mixed valent Cu(II)-Cu(I) interlinked molecular assembly with a very unusual bridging property of the hydrazone ligand. An extraordinary in situ partial Cu(II)→ Cu(I) reduction is observed in this system at room temperature.