- Synthesis and structural characterization of (E)-N′-((Pyridin-2-yl) methylene) benzohydrazide by X-ray diffraction, FT-IR, FT-Raman and DFT methods
-
The (E)-N′-((Pyridin-2-yl)methylene)benzohydrazide (PMBH) was synthesized and its structural characterization was made by the X-ray diffraction method. The spectral investigations such as FT-IR, FT-Raman and UV-Visible spectra were carried out. The record
- Ramesh Babu,Subashchandrabose,Padusha, M. Syed Ali,Saleem,Manivannan,Erdo?du
-
-
Read Online
- Experimental and quantum computational study of two new bridged copper(II) coordination complexes as possible models for antioxidant superoxide dismutase: Molecular structures, X-band electron paramagnetic spectra and cryogenic magnetic properties
-
In the present study, we use a dual approach comprising experimental and quantum computational studies of two new bridged copper(II) coordination complexes with NNO donor ligands, viz., [Cu2(μ-sulfato)(L)2(2H2O)]·1.5H
- Singh, Yogendra,Patel,Patel, Satish Kumar,Patel, Abhay Kumar,Patel,Singh, Rita,Butcher,Jasinski, Jerry P.,Gutierrez
-
-
Read Online
- Carboxylate-bridged copper(II) complexes: Synthesis, crystal structures, and superoxide dismutase activity
-
Two copper(II) complexes, [Cu2(-benzoato)(L1)2]NO3·2H2O (1) and [Cu2(-succinato)(L2)2(H2O)]ClO4 (2), have been synthesized, where L1 = N′-[(E)-phenyl(pyridin-2-yl)methylidene] benzoylhydrazone and L2 = N′-[(E)-p
- Patel, Ram N.,Patel, Dinesh K.,Shukla, Krishna K.,Singh, Yogendra
-
-
Read Online
- N-acylhydrazones confer inhibitory efficacy against New Delhi metallo-β-lactamase-1
-
The expression of β-lactamases, especially metallo-β-lactamases (MβLs) in bacteria is one of the main causes of drug resistance. In this work, an effective N-acylhydrazone scaffold as MβL inhibitor was constructed and characterized. The biological activity assays indicated that the synthesized N-acylhydrazones 1–11 preferentially inhibited MβL NDM-1, and 1 was found to be the most effective inhibitor with an IC50 of 1.2 μM. Analysis of IC50 data revealed a structure–activity relationship, which is that the pyridine and hydroxylbenzene substituents at 2-position improved inhibition of the compounds on NDM-1. ITC and enzyme kinetics assays suggested that it reversibly and competitively inhibited NDM-1 (Ki = 0.29 ± 0.05 μM). The synthesized N-acylhydrazones showed synergistic antibacterial activities with meropenem, reduced 4–16-fold MIC of meropenem on NDM-1- producing E. coli BL21 (DE3), while 1 restored 4-fold activity of meropenem on K. pneumonia expressing NDM-1 (NDM-K. pneumoniae). The mice experiments suggested that 1 combined meropenem to fight against NDM-K. pneumoniae infection in the spleen and liver. Cytotoxicity assays showed that 1 and 2 have low cytotoxicity. This study offered a new framework for the development of NDM-1 inhibitors.
- Gao, Han,Li, Jia-Qi,Kang, Peng-Wei,Chigan, Jia-Zhu,Wang, Huan,Liu, Lu,Xu, Yin-Sui,Zhai, Le,Yang, Ke-Wu
-
-
- Synthesis, characterization, anticancer and antibacterial evaluation of Schiff base ligands derived from hydrazone and their transition metal complexes
-
Copper(II), Nickel(II) and Cobalt(III) complexes with Schiff base ligands derived from hydrazone, (HL1 = (E)-N′-(pyridin-2-ylmethylene)benzohydrazide, H2L2 = (E)-2-(2-hydroxybenzylidene)hydrazine-1-carboxamide and HL3
- Fekri, Roghayeh,Salehi, Mehdi,Asadi, Asadollah,Kubicki, Maciej
-
p. 245 - 254
(2018/10/02)
-
- Kinetic Selectivity and Thermodynamic Features of Competitive Imine Formation in Dynamic Covalent Chemistry
-
The kinetic and thermodynamic selectivities of imine formation have been investigated for several dynamic covalent libraries of aldehydes and amines. Two systems were examined, involving the reaction of different types of primary amino groups (aliphatic amines, alkoxy-amines, hydrazides and hydrazines) with two types of aldehydes, sulfobenzaldehyde and pyridoxal phosphate in aqueous solution at different pD (5.0, 8.5, 11.4) on one hand, 2-pyridinecarboxaldehyde and salicylaldehyde in organic solvents on the other hand. The reactions were performed separately for given amine/aldehyde pairs as well as in competitive conditions between an aldehyde and a mixture of amines. In the latter case, the time evolution of the dynamic covalent libraries generated was followed, taking into consideration the operation of both kinetic and thermodynamic selectivities. The results showed that, in aqueous solution, the imine of the aliphatic amine was not stable, but oxime and hydrazone formed well in a pH dependent way. On the other hand, in organic solvents, the kinetic product was the imine derived from an aliphatic amine and the thermodynamic products were oxime and hydrazone. The insights gained from these experiments provide a basis for the implementation of imine formation in selective derivatization of mono-amines in mixtures as well as of polyfunctional compounds presenting different types of amino groups. They may in principle be extended to other dynamic covalent chemistry systems.
- Kulchat, Sirinan,Chaur, Manuel N.,Lehn, Jean-Marie
-
supporting information
p. 11108 - 11118
(2017/08/22)
-
- Acylhydrazones as Widely Tunable Photoswitches
-
Molecular photoswitches have attracted much attention in biological and materials contexts. Despite the fact that existing classes of these highly interesting functional molecules have been heavily investigated and optimized, distinct obstacles and inherent limitations remain. Considerable synthetic efforts and complex structure-property relationships render the development and exploitation of new photoswitch families difficult. Here, we focus our attention on acylhydrazones: a novel, yet underexploited class of photochromic molecules based on the imine structural motif. We optimized the synthesis of these potent photoswitches and prepared a library of over 40 compounds, bearing different substituents in all four crucial positions of the backbone fragment, and conducted a systematic study of their photochromic properties as a function of structural variation. This modular family of organic photoswitches offers a unique combination of properties and the compounds are easily prepared on large scales within hours, through an atom-economic synthesis, from commercially available starting materials. During our thorough spectroscopic investigations, we identified photoswitches covering a wide range of thermal half-lives of their (Z)-isomers, from short-lived T-type to thermally stable P-type derivatives. By proper substitution, excellent band separation between the absorbance maxima of (E)- and (Z)-isomers in the UV or visible region could be achieved. Our library furthermore includes notable examples of rare negative photochromic systems, and we show that acylhydrazones are highly fatigue resistant and exhibit good quantum yields.
- Van Dijken, Derk Jan,Kova?í?ek, Petr,Ihrig, Svante P.,Hecht, Stefan
-
supporting information
p. 14982 - 14991
(2015/12/08)
-
- Adaptation in constitutional dynamic libraries and networks, switching between orthogonal metalloselection and photoselection processes
-
Constitutional dynamic libraries of hydrazones aAbB and acylhydrazones aAcC undergo reorganization and adaptation in response to a chemical effector (metal cations) or a physical stimulus (light). The set of hydrazones [1A1B, 1A2B, 2A1B, 2A 2B] undergoes metalloselection on addition of zinc cations which drive the amplification of Zn(1A2B)2 by selection of the fittest component 1A2B. The set of acylhydrazones [E-1A1C, 1A2C, 2A1C, 2A2C] undergoes photoselection by irradiation of the system, which causes photoisomerization of E- 1A1C into Z-1A1C with amplification of the latter. The set of acyl hydrazones [E-1A1C, 1A3C, 2A1C, 2A 3C] undergoes a dual adaptation via component exchange and selection in response to two orthogonal external agents: a chemical effector, metal cations, and a physical stimulus, light irradiation. Metalloselection takes place on addition of zinc cations which drive the amplification of Zn( 1A3C)2 by selection of the fittest constituent 1A3C. Photoselection is obtained on irradiation of the acylhydrazones that leads to photoisomerization from E-1A 1C to Z-1A1C configuration with amplification of the latter. These changes may be represented by square constitutional dynamic networks that display up-regulation of the pairs of agonists ( 1A2B, 2A1B), (Z-1A 1C, 2A2C), (1A3C, 2A1C), (Z-1A1C, 2A 3C) and the simultaneous down-regulation of the pairs of antagonists (1A1B, 2A2B), (1A 2C, 2A1C), (E-1A1C, 2A3C), (1A3C, 2A 1C). The orthogonal dual adaptation undergone by the set of acylhydrazones amounts to a network switching process.
- Vantomme, Ghislaine,Jiang, Shimei,Lehn, Jean-Marie
-
supporting information
p. 9509 - 9518
(2014/07/21)
-
- Substituent and solvent effects on intermolecular interactions in crystals of N -acylhydrazone derivatives: Single-crystal X-ray, solid-state NMR, and computational studies
-
New crystalline forms of hydrated and anhydrous N-acylhydrazones are reported. The studied crystal structures were determined by single-crystal X-ray diffraction at 90 or 100 K. Transferred aspherical atom model (TAAM) structure refinements were performed
- Mazur, Liliana,Jarzembska, Katarzyna N.,Kaminski, Radoslaw,Wozniak, Krzysztof,Pindelska, Edyta,Zielinska-Pisklak, Monika
-
p. 2263 - 2281
(2014/05/20)
-
- A light-induced reversible phase separation and its coupling to a dynamic library of imines
-
Irradiation of a 3:2 acetonitrile-water solution of the bis-pyridyl hydrazone 1 and calcium chloride causes a photo-induced phase separation, due to an increase in free calcium cations as a consequence of the photo-conversion of 1 from its E form to the Z
- Vantomme, Ghislaine,Hafezi, Nema,Lehn, Jean-Marie
-
p. 1475 - 1483
(2014/03/21)
-
- Configurational and constitutional information storage: Multiple dynamics in systems based on pyridyl and acyl hydrazones
-
The C=N group of hydrazones can undergo E/Z isomerization both photochemically and thermally, allowing the generation of a closed process that can be tuned by either of these two physical stimuli. On the other hand, hydrazine-exchange reactions enable a constitutional change in a given hydrazone. The two classes of processes: 1) configurational (physically stimulated) and 2) constitutional (chemically stimulated) give access to short-term and long-term information storage, respectively. Such transformations are reported herein for two hydrazones (bis-pyridyl hydrazone and 2-pyridinecarboxaldehyde phenylhydrazone) that undergo a closed, chemically or physically driven process, and, in addition, can be locked or unlocked at will by metal-ion coordination or removal. These features also extend to acyl hydrazones derived from 2-pyridinecarboxaldehyde. Similarly to the terpydine-like hydrazones, such acyl hydrazones can undergo both constitutional and configurational changes, as well as metal-ion coordination. All these types of hydrazones represent dynamic systems capable of acting as multiple state molecular devices, in which the presence of coordination sites furthermore allows the metal ion-controlled locking and unlocking of the interconversion of the different states.
- Chaur, Manuel N.,Collado, Daniel,Lehn, Jean-Marie
-
experimental part
p. 248 - 258
(2011/03/21)
-
- Synthesis and analgesic activity of novel N-acylarylhydrazones and isosters, derived from natural safrole
-
A new series of antinociceptive compounds belonging to the N- acylarylhydrazone (NAH) class were synthesized from natural safrole (7). The most analgesic derivative represented by 10f, [(4'-N,N- dimethylaminobenzylidene-3-(3',4'-methylenedioxyphenyl)propionylhydrazine], was more potent than dipyrone and indomethacin, used as standards. The NAH compounds described herein were structurally planned by molecular hybridization and classical bioisosterism strategies on previously reported analgesic NAH in order to identify the pharmacophoric contribution of the N- acylarylhydrazone moiety and investigate the structure-activity relationship (SAR) in these series. (C) 2000 Editions scientifiques et medicales Elsevier SAS.
- Lima, Patricia C.,Lima, Lidia M.,Da Silva, Kelli Cristine M.,Leda, Paulo Henrique O.,De Miranda, Ana Luisa P.,Fraga, Carlos A. M.,Barreiro, Eliezer J.
-
p. 187 - 203
(2007/10/03)
-
- Potentially tridentate hydrazonic ligands in the synthesis of methyl and acetyl palladium(II) complexes
-
Potentially tridentate hydrazonic ligands of the type HNNO have been used in the synthesis of some methyl palladium(II) complexes. Depending on the applied experimental conditions two different kinds of complexes are obtained. Thus, the reactions between HL1-HL5 and (COD)PdMeCl in diethyl ether led to the formation of bidentate methyl complexes of the type Pd(HNN)MeCl (1-5), where the ligands maintain a neutral character. However, in the presence of a base such as Et3N or NaOMe, the ligands are deprotonated with the consequent formation of tridentate methyl complexes of the type Pd(NNO)Me (7-10). In solution, complexes 1-5 tend to lose the hydrazonic proton with elimination of methane and formation of a tridentate chloride complex Pd(NNO)Cl (6); this tendency can be correlated with the acidity of the free ligands, which has been determined. On bubbling carbon monoxide through solutions of 1-5, the corresponding acetyl complexes Pd(HNN)[C(O)Me]Cl (11-15) are formed, in which both the cis and trans isomers are present. Their molar ratio is rationalised from the results of a molecular modelling study on the basis of electronic considerations. A remarkably different reactivity has been found in the carbonylation of the tridentate complexes 7-10: they decompose rapidly and quantitatively to palladium black and an organic product corresponding to the ligand with an acetyl group bonded to the hydrazonic nitrogen. The X-ray structures of a methyl complex (3) and its corresponding acetyl (13) derivative have been determined.
- Pelagatti, Paolo,Carcelli, Mauro,Franchi, Francesca,Pelizzi, Corrado,Bacchi, Alessia,Fochi, Andrea,Fruehauf, Hans-Werner,Goubitz, Kees,Vrieze, Kees
-
p. 463 - 475
(2007/10/03)
-