Synthesis, characterization and antitumor activity of novel N-substituted α-amino acids containing ferrocenyl pyrazole-moiety

A series of new N-[(3-ferrocenyl-1-phenylpyrazol-4-yl)methyl] α-amino acids were prepared and characterized by a range of spectroscopic techniques and cyclic voltammetry. The in vitro antitumor activity of all synthesized compounds was investigated against cervix adenocarcinoma HeLa, melanoma Fem-x and myelogenous leukemia K562 cell lines using the MTT method. Tryptophan derivative 1l exhibited the highest cytotoxic activity in the cell growth inhibition of all three types of cell lines.     

Substituted Pyrazoles and Their Heteroannulated Analogs—Recent Syntheses and Biological Activities

Pyrazoles are considered privileged scaffolds in medicinal chemistry. Previous reviews have discussed the importance of pyrazoles and their biological activities; however, few have dealt with the chemistry and the biology of heteroannulated derivatives. Therefore, we focused our attention on recent topics, up until 2020, for the synthesis of pyrazoles, their heteroannulated derivatives, and their applications as biologically active moieties. Moreover, we focused on traditional procedures used in the synthesis of pyrazoles.     

Glucose‐coated superparamagnetic nanoparticle‐catalysed pyrazole synthesis in water

A green, benign, heterogeneous, superparamagnetic catalyst (Glu.@Fe₃O₄) was synthesized and characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy and vibrating sample magnetometry. The prepared catalyst was used to achieve a high‐efficiency, low‐cost, eco‐friendly and easy‐to‐handle protocol for synthesizing substituted pyrazole derivatives from aldehydes, malononitrile and phenylhydrazine. The catalyst was also used in chromene synthesis. Glucose coated on magnetic nanoparticles provided excellent catalytic activity. The catalyst could be recycled for up to four runs without significant loss in catalytic activity.     

超声辐射下几种腙类化合物的合成研究

以乙酰丙酮为起始原料,经三步反应制得了w-溴代-1-苯基-5-甲基吡唑-4-乙酮(5).中间体5在超声波辐射下与芳基乙酮缩氨基硫脲类化合物(1a-1g)反应生成了新型的N-(1-芳基乙酮)-N1-[(1-苯基-5-甲基吡唑-4-基)噻唑-2-基]腙(6a-6g).以1H NMR,IR,MS和元素分析对产物进行了确证及表...     

Copper-Catalyzed Synthesis of 5-Aryl-6-(Trifluoromethyl)-2,3-Dihydropyrazolo[1,2-a]Pyrazol-1(5H)-One

An efficient protocol for the synthesis of 5-aryl-6-(trifluoromethyl)-2,3-dihydropyrazolo[1,2-a]pyrazol-1(5H)-one derivatives through a copper-catalyzed [3+2]-cycloaddition of azomethine imines with 3,3,3-trifluoropropyne (generated in situ from dehydrobromination of 2-bromo-3,3,3-trifluoropropene under base conditions) is developed. The advantages of this transformation are the broad substrate scope and the good functional group compatibility. The subsequent oxidation and nucleophilic substitution/aromatization provide a new approach to 4-trifluoromethylated pyrazol-1-yl propanoic acids.     

Access to Silylated Pyrazole Derivatives by Palladium‐Catalyzed C−H Activation of a TMS group

A simple and efficient approach to new silylated heterocycles of potential interest in medicinal chemistry is presented. A set of bromophenyl trimethylsilyl pyrazole intermediates can be transformed by direct organometallic routes into two families of regioisomeric iodoaryl substrates; using either arylzinc or aryllithium chemistry, the TMS group remains on the pyrazole ring or translocates to the aryl moiety. These two families can then be efficiently transformed into benzo silino pyrazoles thanks to a single‐step cyclization relying on the Pd‐catalyzed activation of a non‐activated C(sp³)?H bond alpha to a silicon atom. The experimental conditions used, which are fully compatible with the pyrazole ring, suggest that this reaction evolves through a concerted metalation–deprotonation (CMD) mechanism.     

Synthesis,Crystal Structure and Biological Activity of 2-(1-(3-Bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carbonyl)piperidin-4-yl)-N-isopropyl-1,3-thiazole-4-carboxamide

The title compound 2-(1-(3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carbonyl)piperidin-4-yl)-N-isopropylthiazole-4-carboxamide(C21H22Br Cl N6O2 S,Mr = 536.04) has been synthesized,and its structure was characterized by IR spectra,1H-NMR,13C-NMR,EA,and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic system,space group P/c with a = 15.146(3),b = 11.573(2),c = 26.937(5) ?,β = 103.64(3)°,V = 1839.0(6) ?3,Z = 4,Dc = 1.557 g/cm3,μ(Mo Ka) = 0.71073 mm-1,F(000) = 2192,R = 0.0601 and w R = 0.1392.There exist one intramolecular hydrogen bond at N–H···N and four intermolecular weak interactions at O(2)···H(1),Cl(1)···H(12),O(1)···Cl(1) and S(1)···O(2).Bioassay results indicated that the title compound had good fungicidal and antiviral activities against tobacco mosaic virus.     

Synthesis of New Benzopyrano[2,3-c]pyrazoles and 3-triazolonyliminocoumarins From 3-cyano Iminocoumarin Derivatives

Synthesis of benzopyrano[2,3-c]pyrazoles and 3-triazolonyliminocoumarins was successfully performed using heterocyclization of 3-cyano iminocoumarin or their N-ethoxycarbonylated derivatives with semicarbazide reagents. Elemental analysis, infrared, and ¹H NMR spectral data confirmed the molecular structure of the newly synthesized compounds.     

Convenient synthesis of spiro[indoline-3,4'-pyrano[2,3-c]pyrazole] and spiro[acenaphthyl-3,4'-pyrano[2,3-c]pyrazoles] via fourcomponent reaction

The base promoted four-component reaction of hydrated hydrazine, dimethyl acetylenedicarboxylate, isatines and malononitrile (ethyl cycanoacetate) in ethanol afforded polysubstituted spiro[indoline-3,4‘-pyrano[2,3-c]pyrazoles] and spiro[acenaphthyl-3,4-pyrano[2,3-c]pyrazoles]     

An Efficient Four-Component Synthesis of Multisubstituted Pyrano[2,3-c]pyrazole

A series of substituted pyrano[2,3-c]pyrazole derivatives were synthesized by a one-pot reaction of methyl 4-methyl-3-oxovalerate, phenylhydrazine, aromatic aldehyde, and malononitrile in ethanol with catalysis by triethylamine. The title compounds were obtained in good to excellent yields. A possible mechanism for this reaction was proposed.