液相色谱-串联质谱法同时测定葡萄酒中6种吡唑类杀菌剂

采用液相色谱-串联质谱建立了同时测定葡萄酒中戊苯吡菌胺、氟唑菌酰胺、吡唑萘菌胺、吡咪唑、联苯吡菌胺、呋吡菌胺6种吡唑类杀菌剂的分析方法。样品用超纯水稀释混匀,经HLB固相萃取柱净化后,采用Agilent ZOBRAX C18色谱柱(2.1 mm×150 mm,5μm)分离;以0.1%乙酸水溶液-乙腈为流动相进行梯度洗脱,目标分析物在多反应监测(MRM)模式下进行定性分析,外标法定量。在优化实验条件下,6种吡唑类杀菌剂在1.0~50.0μg·L-1范围内呈良好的线性关系,相关系数(r2)均不低于0.999 3,方法定量下限为0.1~0.4μg·kg-1。在低、中、高3个加标水平下的平均回收率为72.8%~92.6%,相对标准偏差(RSD)不大于6.7%。该方法简便快速、灵敏度高,可用于葡萄酒中吡唑类杀菌剂的测定。     

Synthesis and Properties of Azoles Containing Benzothiazole Substituents. (Review)

The results from investigations into the synthesis and properties of five-membered nitrogen-containing heterocycles with several heteroatoms, including benzothiazole fragments, are reviewed.     

Synthesis,crystal structure,and insecticidal evaluation of novel aryl pyrazole compounds containing aminophosphonate moiety

A series of novel aryl pyrazole derivatives containing aminophosphonate were designed and synthesized on the basis of the commercial insecticide Fipronil. Their structures were confirmed by ¹H NMR, FT-IR, elemental analysis, and compound 4 m was characterized by a single crystal X-ray diffraction analysis. The results of the preliminary bioassays showed that title compounds exhibited satisfactory insecticidal activities against Culex pipiens and Musca domestica. The introduction of an electron-withdrawing group to the para-position of the benzene ring was essential for high bioactivity.     

Morpholine triflate promoted one-pot,four-component synthesis of dihydropyrano[2,3-c] pyrazoles

A one-pot,four-component reaction of ethyl acetoacetate,hydrazine hydrate,aldehydes,and malononitrile was discussed using Lewis acid catalyst morpholine triflate (MorT) to afford a series of dihydropyrano[2,3-c] pyrazoles,which were generally catalyzed by organic alkalis.Moderate to excellent yields,no chromatographic purification,and evasion of environmentally hazardous solvents in the reaction process make this protocol very useful for academia and industry.     

Subtle difference of [SiMo12O40]4− and [PMo12O40]3− inducing two new distinct Keggin-Ag-(1H-Pyrazole) compounds

Two new inorganic-organic hybrid compounds based on α-Keggin clusters and Ag-(1H-Pyrazole) subunits, [AgL₂]₄[SiMo₁₂O₄₀] (1) and [AgL₂]₃[PMo₁₂O₄₀] (2) (L = pyrazole), have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction. In 1, there are two kinds of chains, the chains linked by two [AgL₂]⁺ clusters and the other linked only by one [AgL₂]⁺, which further connect by sharing [SiMo₁₂O₄₀]^4? anions to construct a 2-D layer. In 2, four-supporting [PMo₁₂O₄₀]^3? anions are fused by [Ag(1)L₂]⁺ subunits to form a 1-D chain. Through weak interactions of Ag?O (3.091 Å) a 2-D supramolecular layer is constructed. Additionally, the electrochemical properties of title compounds and the photocatalytic properties of 2 have been studied.     

Synthesis and characterization of two Cu(II) complexes with a new pyrazole-based Schiff base ligand: crystallography,DNA interaction and antimicrobial activity of Ni(II) and Cu(II) complexes

Reaction of Cu(II) nitrate with a new pyrazole-based Schiff base ligand, 5-methyl-3-formylpyrazole-N-(2′-methylphenoxy)methyleneimine (MPzOA), afforded two types of Cu(II) complexes at different reaction temperatures, [Cu(MP_zOA)(NO₃)]₂ (1) and [Cu(3,7,11,15-tetramethylporphyrin)(H₂O)](NO₃)₂ (2), reported together with a Ni(II) complex, [Ni(MPzOA)₂(H₂O)₂]Br₂ (3). The compounds are characterized by single crystal X-ray structure analyses along with several physico-chemical and spectral parameters. Complex 1 is authenticated as a bis(μ-pyrazolato)dicopper(II), while 2 is a porphyrinogen and 3 is a distorted octahedral complex. Structural analyses of the complexes reveal that 1 crystallized in monoclinic P2₁/n space group while 2 and 3 crystallized in monoclinic C2/c space group. DNA-binding studies of the complexes have shown that the complexes interact with CT-DNA. DNA-cleavage studies with plasmid DNA have shown that 1 and 2 induce extensive DNA cleavage in the presence of H₂O₂ as an additive, whereas there is no change in degradation of super-coiled DNA by 3 in the presence of additive. The antimicrobial studies of the complexes against Escherichia coli DH5α bacteria strain indicated that all the complexes were capable of killing E. coli with different LD50 values.     

Synthesis and Reactivity of Enaminones: Synthesis of Some 1,3,4‐Thiadiazole Linked to Pyrazole,Pyridine, Benzimidazolopyrimidine,Pyrazolopyrimidine, Pyrazolotriazine and Triazolotriazine Derivatives

1,3,4‐Thiadiazole‐enaminone ( 6 ) was synthesized via reaction of the benzamide ( 5 ) with DMF‐DMA. The simple thiadiazole‐enaminone ( 6 ) was used as a synthetic precursor for the synthesis of a wide variety of new heterocyclic compounds, including the 5‐substituted‐1,3,4‐thiadiazole derivatives ( 7 ), ( 8 ), ( 16 ), ( 17 ) and ( 18 ), which were obtained via reactions of ( 6 ) with nitrogen nucleophiles. Also, reactions of enaminone ( 6 ) with carbon nucleophiles afforded the respective 1,3,4‐thiadiazoles ( 10a , 10b ). Diazotization of the benzamide ( 20 ) with the heteroaromatic amine salts gave the hydrazone derivatives ( 21 ) and ( 22 ). Cyclization of the latter hydrazones yielded the corresponding pyrazolotriazine and 1,2,4‐triazolotriazine derivatives ( 23 ) and ( 24 ), respectively. All newly synthesized compounds were elucidated by considering the data of both elemental and spectral analysis.     

Production of Dihydrogen Using Ammonia Borane as Reagent and Pyrazole as Catalyst

Theoretical chemistry (DLPNO-CCSD(T)/def2-TZVP//M06-2x/aug-cc-pVDZ) was used to design a system based on ammonia boranes catalyzed by pyrazoles with the aim of producing dihydrogen, nowadays of high interest as clean fuel. The reactivity of ammonia borane and cyclotriborazane were investigated, including catalytic activation through 1H-pyrazole, 4-methoxy-1H-pyrazole, and 4-nitro-1H-pyrazole. The results point toward a catalytic cycle by which, at the same time, ammonia borane can initially store and then, through catalysis, produce dihydrogen and amino borane. Subsequently, amino borane can trimerize to form cyclotriborazane that, in presence of the same catalyst, can also produce dihydrogen. This study proposes therefore a consistent progress in using environmentally sustainable (metal free) catalysts to efficiently extract dihydrogen from small B−N bonded molecules.