Dual-parameter Correlation Analysis of the Fluorescence Data of 1-Methyl-2-formyl-5-substituted Pyrrole(4-nitrophenyl)hydrazones

By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence spectra have been measured. Correlation results show that the Delta E-em values are mainly affected by polar effects, but spin-delocalizatin effects also exist.

Synthesis and Characterization of Dimeric Copper（ll） and Nickel（ll） Complexes with Some Aroylhydrazones of a-Pyridoin and Solvent Extraction Applications

A new series of dimeric Cu（II） and Ni（II） complexes with some aroylhydrazones of a-pyridoin were synthesized and characterized using different physical techniques. Their chemical formulae were based on their microanalysis and IR data. The structures of the solid complexes were determined from the electronic, IR and ESR spectral studies as well as their magnetic susceptibility measurements. The ligands acted as bi-, tri- and tetra-dentate forming different dinuclear complexes with different structures. The assumed molecular structures based on the experimental results were also confirmed by the molecular mechanics calculations. The extraction ability of the hydrazones has been investigated by liquid-liquid extraction for Cu（II） and Ni（II）.

Synthesis, Crystal Structure and Antibacterial Activity of Two Hydrazones Derived from 2-Fluorobenzhydrazide

Two new Schiff base benzoyl hydrazone compounds, C14H10FN3O3 （Ⅰ） and C14H10F2N2O （Ⅱ）, have been synthesized and characterized by elemental analysis, IR, UV and X-ray single-crystal diffraction. Both compounds crystallize in monoclinic, space group P21/c with a = 7.0514（14）, b = 25.928（5）, c = 7.7099（15）, β = 111.823（2）°, V = 1308.6（4）3, Z = 4, C14H10FN3O3, Mr = 287.25, Dc = 1.458 g/cm3, μ（MoKα） = 0.115 mm-1, F（000） = 592, the final R = 0.0841 and wR = 0.2489 for 1901 observed reflections （I 2σ（I）） for I; a = 11.232（3）, b =12.735（4）, c = 8.612（2） , β = 90.869（3）°, V = 1231.7（6）3, Z = 4, C14H10F2N2O, Mr = 260.24, Dc = 1.403 g/cm3, μ（MoKα） = 0.111 mm-1, F（000） = 536, the final R = 0.0453 and wR = 0.1085 for 1317 observed reflections （I 2σ（I）） for Ⅱ. The antibacterial activities of both compounds against two bacteria were first studied and one compound showed considerable antibacterial activity against K. Pneumonia and S. aureus.

Studies on Lead(Ⅱ) Complexes of Ferrocenylaldehyde Aroylhydrazones

The complexes of four ferrocenylaldehyde aroylhydrazones with lead(Ⅱ) were synthesized and characterized. Their compositions, bonding forms and properties were researched by means of elemental analysis, IR, UV Vis, 1H NMR spectra, thermal analysis and molar conductance. The free ligands which existed in the keto form coordinated to lead(Ⅱ) in the enol form to form neutral complexes. The molar ratio of the ligand to lead(Ⅱ) is 2∶1 and the thermal stability of the complex is higher than that of the corresponding ligand because of the formation of the stable chelate ring. The ligands and the complexes are all non electrolytes.

The Synthesis of Aromatic Hydrazones as Nitrogen-Containing Prostaglandin Congeners

We synthesized a series of hydrazones, a novel type of nitrogen-containing prostaglandins, from different aromatic hydrazines and variant 2-substituted amino-3-hydroxy bicycle [3.2.0]hept-6-ones IV.

Who is Who in the Carbene Chemistry of N-Sulfonyl Hydrazones

Over the past few decades,N-sulfonyl hydrazones have been recognized as alternative precursors for hazardous diazo compounds in organic synthesis,allowing for diverse innovative and original chemical transformations that were otherwise difficult to achieve.This critical review summarizes the major advancements in the carbene chemistry of N-sulfonyl hydrazones.The contents of this review are organized based on research conducted by leading scientists who have made significant contributions to this field.The individual carbene transfer reactions and their mechanisms,as well as the potential applications in the synthesis of natural products and complex bioactive molecules,are thoroughly discussed.

Fluoroalkyl N-sulfonyl hydrazones:An efficient reagent for the synthesis of fluoroalkylated compounds

Fluoroalkyl N-sulfonyl hydrazones are versatile reagents that can be used to synthesize a wide range of diverse fluoroalkylated organic molecules.Although it has been known since 1975,the chemistry of fluoroalkyl N-sulfonyl hydrazones has recently only received great attention from the scientific community.Generally,they are used as either safe and bench-stable diazo precursors in carbene transfer reactions or as 1,3-dipoles in cycloaddition and cyclization reactions.Notably,fluoroalkyl N-sulfonyl hydrazones to replace toxic fluoroalkyl diazo compounds in carbene transfer reactions reduce the risk of rapid accumulation of explosive diazo compounds and improve functional group compatibility and substrate scope.Given the growing importance of fluoroalkyl N-sulfonyl hydrazones in chemical synthesis,a comprehensive review of this topic in the literature is essential to demonstrate their synthetic potential.In this review,we critically summarize and comprehensively analyze the publications in various literatures on the chemistry of fluoroalkyl N-sulfonyl hydrazones starting from 1990 to date.The classification of the different reactivity profiles of fluoroalkyl N-sulfonyl hydrazones and the efficiencies of similar types of reactions or substrates with fluoroalkyl diazo compounds are compared.

Synthesis and Physico-Chemical Characterizations of Novel Hydrazone Ligands and Their Metal Complexes against Hormone-Dependent and Independent Cancers

This work deals with the synthesis and physicochemical characterizations of a new group of novel retinoidal ligands and their metal complexes. Their in vitro anti-proliferative activities have shown that ligand L1 is effective against human breast cancer BT-20 and MCF-7 cell lines. At the same time, compound L2 exerts its effect on human prostate cancer PC-3 and human breast cancer MDA-MB-231 and MCF-7 cell lines respectively. The retinoid ligands exert their pleiotropic action toward retinoic acid receptors (RARs) than their metal complexes but all compounds exhibit concentration-dependent.

Cascade reaction to 1H-pyrazoles from hydrazones via sodium Ni-trite promoted dual C-C/C-N formation,annulation and aromatization with 1,2-dichloroethane

A novel route for tandem C-C/C-N formation,annulation and aromatization of hydrazones with 1,2-dichloroethane to synthesize 1 H-pyrazoles has been developed.Furthermore,the 1,2-dichloroethane serves as alkylation reagent in good to excellent yields.This methodology features mild reaction conditions and good functional group tolerance,providing a direct approach for the preparation of 1 Hpvrazoles.

Synthesis, Characterization and Antimicrobial Activity of Oxovanadium（IV） Complexes of Schiff Base Hydrazones Containing Quinoxaline Moiety

The oxovanadium（IV） complexes of the Schiff base hydrazones, synthesized from 3-hydrazinoquinoxaline-2- one （HQO） with salicylaldehyde （HSHQO）, o-hydroxyacetophenone （HHAHQO）, dehydroacetic acid （HDHAHQO） and o-nitrobenzaldehyde （NBHQO） were synthesized and characterized on the basis of analytical, conductance, magnetic moment, infrared, NMR, ESR and electronic spectral data. The ligands HSHQO, HDHAHQO behaved as monobasic tridentate ONN donors through phenolic oxygen, azomethine nitrogens. The ligand HAHQO acted as a monobasic bidentate ON donor through the phenolic oxygen, azomethine （free） nitrogen and the ligand NBHQO acted as neutral bidentate ON donor through oxygen of the nitro group and azomethine （free） nitrogen.

Cyclization of 2-methoxy-6-(substituted benzyloxy)acetophenone hydrazones in the presence of polyphosphoric acid(PPA)

Cyclization of 2-methoxy-6-benzyloxy acetophenone hydrazone gave 3-methyl-4-meth- oxy indazole and 3-methyl-4-methoxy-7-benzyl indazole in the presence of polyphosphoric acid (PPA).The hydrazone was probably converted to 2-hydroxy-6-methoxy acetophenone hydra- zone and 2-hydroxy-3-benzyl-6-methoxy acetophenone hydrazone followed by cyclization to the corresponding indazoles in acidic conditions.Cyelization of 2-methoxy-6-(halo or alkyl or aryl benzyloxy)acetophenone hydrazones gave similar products.Cyclization of 2-methoxy-6- (p-nitrobenzyloxy)acetophenone hydrazone gave 2-(p-nitrophenyl)-3-methyl-4-methoxy benzo- furan and 3-methyl-4-methoxy indazole while 2-methoxy-6-(m-nitrobenzyloxy)acetophenone hydrazone gave 3-methyl-4-methoxy indazole,3-methyl-4-methoxy-7-(m-nitrophenyl)indazole and 3-methyl-4-(m-nitrobenzyloxy)indazole.

Efficient Construction and Structure Determination of Novel Macrocycles with Calixarene Bishydrazones

A series of large macrocyclic calixarene bishydrazones were efficiently synthesized by [2 ＋ 2] condensation reactions of calix[4]arene 1,3-disubstituted aldehydes with hydrated hydrazine. The X-ray single crystal diffraction showed that macrocycles form a distinctive calixtube-liking shape.

Cycloaddition of hydrazones and 1,2-diarylalkynes promoted by t-BuOK/DMF:A convenient synthesis of tetraarylpyrazoles

A facile synthesis of tetraarylpyrazoles has been developed via t-BuOK/DMF promoted intermolecular cycloaddition of hydrazones and 1,2-diarylalkynes. A possible reaction pathway via a hydrazone radical is proposed.

Base-Promoted Catalyst-Free Regioselective Hydroacylation of Styrenes with Hydrazones via Carbanion Addition

Wereport a base-promoted catalyst-free protocol for the highly regioselective hydroacylation of styrenes with hydrazones derived from naturally abundant aldehydes.This protocolgeneratedlinearketoneswith goodfunctional grouptolerance anda broadsubstrate scope under mild conditions.Mechanistic studies showed that the addition of hydrazone anion to a styrene double bond was the key step,different from previoushydroacylationpathways(viaorganometallic complexes or radical intermediates).

Unconventional assemblies of bisacylhydrazones:The role of water for circularly polarized luminescence

Understanding the precise molecular arrangement of chiral supramolecular polymers is essential not only to comprehend complex superstructures like proteins and DNA but also for the development of next-generation optoelectronic materials,including materials displaying high-performance circularly polarized luminescence(CPL).Herein,we report the first chiral supramolecular polymer systems based on hydrazone–pyridinium conjugates comprising alkyl chains of different lengths,which afforded control of the apparent supramolecular chirality.Although supramolecular chirality is governed basically by the remote chiral centers of alkyl chains,helicity inversion was achieved by controlling the conditions under which the hydrazone building blocks underwent aggregation(i.e.,solvent compositions or temperature).More importantly,the addition of water to the system led to aggregationinduced hydrazone deprotonation,which resulted in a completely different selfassembly behavior.Structural water molecules played an essential role,forming the assembly’s channel-like backbone,around which hydrazone molecules gathered as a result of hydrogen bonding interactions.Further co-assembly of an achiral hydrazone luminophore with the given supramolecular polymer system allowed the fabrication of a novel CPL-active hydrazone-based material exhibiting a high maximum value for the photoluminescence dissymmetry factor of -2.6×10^(-2).

Preparation of twelve 1-methyl-2-formyl-5-substituted pyrroles and their hydrazones

Preparation of twelve 1-methyl-2-formyl-5-substituted pyrroles (2a–1), with five of them as new compounds, is described. Their derivatives, i.e., 1-methyl-2-formyl-5-substituted pyrrole phenyl hydrazones (3a–1) and 1-methyl-2-formyl-5-substituted pyrrole (4-nitrophenyl) hydrazones (4a–1) are all new compounds. They have also been prepared and further identified.

Physicochemical Properties and Biological Activities of Novel Hydrazonate Copper Complexes

The objective of this research was to elucidate the biological effect of novel compounds derived from natural product of syringaldehyde through novel semi-synthetic method in order to investigate the physicochemical properties and biological activities by using DPPH and FRAP techniques and its antibacterial activities against Klebsiella spp., Pseudomonas aeruginosa, Bacillus cereus, and Staphylococcus aureus. Moreover, to examine its ability against breast cancer cell line (MCF-7). The results showed that the syringaldehyde hydrazonate copper complexes possessed the covalent bonds with square-planar structure. In terms of antioxidant DPPH activities, it was found that syringaldehyde hydrazone possessed high potency against DPPH free radicals, with respect to syringaldehyde hydrazonate copper complexes. On the other hand, all compounds possessed low reducing properties for changing Fe3+ to Fe2+ in FRAP technique. For antibacterial activities revealed that the ligand L1 and L5 possessed high effect on Pseudomonas aeruginosa, but for all copper complexes possessed high potent antibacterial susceptibility to four bacteria with concentration dependence. For anti-breast cancer cell line (MCF-7), it was found that all compounds possessed high potent anticancer susceptibility with low IC50, especially, compound exhibit highly potency effective is C5 (IC50 9.75 μM). The tendency of anticancer effect from high to low was C5 > C2 > C1 > C4 > C3. Therefore, all synthetic compounds obtained from the present research possibly develop as the antibacterial drugs and the drugs for curing the diseases caused by free radicals, including breast cancer in metastatic phase. The most important feature of these drugs was the high specificity to the target and harmless to the normal cells.

Synthesis, Characterization and Antibacterial Activity of Biologically Important Vanillin Related Hydrazone Derivatives

Hydrazone derivatives of vanillin are found to possess anti-bacterial activities. Based on higher bio-activity of hydrazones, new hydrazone derivatives were synthesized from Piperdine-4-carboxylicacid methyl ester (1). The compounds 1-pyrimidine-2-yl piperidine-4-carboxylicacid(4-hydroxy-3-methoxy benzylidine)-hy- drazide (10), 1-pyrimidine-2-yl piperidine-4-carboxylicacid (3,4-dimethoxy benzylidine) hydrazide (11), 1-pyrimidine-2-yl piperidine-4-carboxylicacid(4-butoxy-3-methoxy benzylidine)-hydrazide (12), 1-pyr- imidine-2-yl piperidine-4-carboxylicacid(3-methoxy-4(2-methoxy ethoxy) benzylidine)-hydrazide (13) were synthesized, purified and characterized by 1HNMR, 13CNMR, LCMS, FT-IR and HPLC techniques. The synthesized hydrazone derivatives were further checked for anti-bacterial activities by paper disc diffusion method against Pseudomonas aeruginosa and Staphylococcus aureus bacterial strains.

Synthesis of 1, 4-Bis[3-N-propionyl-2-aryl-1, 3, 4- oxadiazoline-5-yl]phenylenes

1, 4-Bis[3-N-propionyl-2-aryl-1, 3, 4-oxadiazoline-5-yl]phenylenes 4 were synthesized by cyclization of corresponding hydrazones 3 with propionic anhydride.

Synthesis and PAMPA Permeability Assay of New Sulfonyl Hydrazone Derivatives

This work describes the synthesis of seven new sulfonyl hydrazones, which were proposed from the general structure of acyl hydrazones and 2,4-dinitrosulfonamides. Sulfonyl hydrazones are a class of compounds known to exhibit a wide range of biological activity. In this sense, the study of the pharmacokinetic properties of the bioactive molecules is of extreme importance;therefore, in this article the permeability of these compounds with in vitro PAMPA assay mimetizing the permeability through the gastrointestinal tract as well as lipophilicity through miLogP was investigated. All compounds presented good permeability results;it was possible to make a structure-activity relationship with the obtained results and a comparison between the results.