Zur Bestimmung des Insecticides 4-Dimethylamino-m-tolyl-methylcarbamidat

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气相色谱-串联质谱法同时测定蔬菜中4种杀菌剂残留量

提出了气相色谱-串联质谱法同时测定蔬菜中甲霜灵、腐霉利、苯醚甲环唑和恶唑菌酮等4种杀菌剂残留量的方法。蔬菜样品经乙酸乙酯提取浓缩后,乙酸乙酯溶解。用BR-5MS毛细管色谱柱为固定相进行色谱分离,质谱分析中采用多反应监测模式。4种杀菌剂的质量浓度均在0.05~0.40mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.001~0.029mg·L-1之间。以空白样品为基体进行加标回收试验,所得回收率在75.6%~102%之间,测定值的相对标准偏差(n=6)在0.6%~6.2%之间。     

Synthesis of Unprecedented 4d/4f-Polypnictogens

A series of 4d/4f-polyarsenides, -polyarsines and -polystibines was obtained by reduction of the Mo-pnictide precursor complexes [{Cp^tMo(CO)₂}₂(μ,η^2:2-E₂)] (E=As, Sb; Cp^t=tBu substituted cyclopentadienyl) with two different divalent samarocenes [Cp*₂Sm] and [(Cp^Me4nPr)₂Sm]. For the reductive conversion of the Mo-stibide only one product was isolated, featuring a planar tetrastibacyclobutadiene moiety as an unprecedented ligand for organometallic compounds. For the corresponding Mo-arsenide a tetraarsacyclobutadiene and a second species with a side-on coordinated As₂²⁻ anion was isolated. The latter can be considered as reaction intermediate for the formation of the tetraarsacyclobutadiene.     

Targeted Synthesis of Anthranilic Diamides Insecticides Containing Trifluoroethoxyl Phenylpyrazole

Aseries of novel anthranilic diamides analogues(9a-9t) containing trifluoroethoxyl pyrazole moiety was designed and synthesized and their insecticidal bioactivities against Mythimna separata(Walker, M. separata) and Plutellaxylostella (P. xylostella) were evaluated. The structures of the title compounds were confirmed by ¹H NMR, ¹³C NMR and HRMS. Preliminary insecticidal activities showed that some of the title compounds possessed good to excellent bioactivities towards M. separata and P. xylostella. Compounds 9c and 9t exhibited 100% mortality rate against M. separate at 0.2 mg/L. For the P. xylostella, the synthesized compounds(9c-9e, 9i and 9o) showed 70%, 80%, 75%, 65% and 60% insecticidal activities at 1×10^-6 mg/L, respectively, higher than that of chlorantraniliprole(0). Based on excellent insecticidal activities, the mode of the action was tested by the calcium-imaging technique, the results of which demonstrated that the novel compounds shared the same target with chlorantraniliprole. The binding pose of the most active compound 9t in RyRs of P. xylostella was predicted by molecular docking, which showed that compound 9t interacted with the residues Glu140(A) and His147(A) via hydrogen bond.     

An Efficient Synthesis of Pyrethroid Insecticides Containing Spiro-fused Cyclopropane Carboxylate

Among the active pyrethroid insecticides containing various substituted cyclpropanecarboxylates, esters derived from 2,2-dimethyl-5,6-benzospiro [2,4] heptene-1-carboxylic acid (1) have been 1 found to have particularly high activity, Our continuing interest in the synthesis of novel pyrethroid insecticides2 led us to a study of synthetic methodology for constructing spiro-fused systems such as (1).     

Synthesis of N4-acylspermidines

N⁴-Acylspermidines have been synthesised in good yields from γ-aminobutyric acid and from spermidine.     

Fe3O4/g-C3N4磁性固相萃取湖水中的3种苯甲酰脲杀虫剂

建立了Fe3O4/g-C3N4磁性固相萃取,结合高效液相色谱-可变波长紫外检测,用于测定湖水中3种苯甲酰脲杀虫剂的新方法.实验考察了溶液pH、离子强度、吸附剂用量、吸附时间、洗脱溶剂种类和体积对3种目标物回收率的影响.在最优实验条件下,氟铃脲和虱螨脲在0.50～500 ng/mL(r≥0.9997)、氟啶脲在0.20～...     

Synthesis and spectroscopic characterization of P-doped Na4Si4

Na₄Si₄ is a Zintl salt composed of Na⁺ cations and tetrahedral anions and is a unique solid-state precursor to clathrate structures and nanomaterials. In order to provide opportunities for the synthesis of complex materials, phosphorus was explored as a possible substituent for silicon. Phosphorus doped sodium silicides Na₄Si_4−xP_x (x≤0.04) were prepared by reaction of Na with the mechanically alloyed Si_4−x:P_x (x=0.04, 0.08, 0.12) mixture in a sealed Nb tube at 650 °C for 3 days. Energy dispersive X-ray spectroscopy confirms the presence of P in all products. Powder X-ray diffraction patterns are consistent with the retention of the Na₄Si₄ crystal structure. As the amount of P increases, a new peak in the diffraction pattern that can be assigned to black phosphorus is apparent above the background. Raman and solid-state NMR provide information on phosphorus substitution in the Na₄Si₄ structure. Raman spectroscopy shows a shift of the most intense band assigned to the ν₁ (A₁) mode from 486.4 to 484.0 cm⁻¹ with increasing P, consistent with P replacement of Si. Differential nuclear spin-lattice relaxation for the Si sites determined via ²⁹Si solid-state NMR provides direct evidence for Si-P bonding in the (Si_1−xP_x)⁴⁻ tetrahedron. The ²³Na NMR shows additional Na…P interactions and the ³¹P NMR shows two P sites, consistent with P presence in both of the crystallographic sites in the (Si₄)⁴⁻ tetrahedron.     

Synthesis,Bioactivity Evaluation,3D-QSAR,and Molecular Docking of Novel Pyrazole-4-carbohydrazides as Potential Fungicides Targeting Succinate Dehydrogenase

To screen novel antifungal agents targeting the succinate dehydrogenase(SDH),a series of pyrazole-4-carbohydrazides were rationally designed,synthesized,and characterized under the guidance of the structures of succinate dehydrogenase inhibitors(SDHIs).Bioassay results in vitro indicated that most of the target compounds exhibited excellent activity against Rhizoctonia solani(R.solani),Fusarium graminearum(F.graminearum),Botrytis cinerea(B.cinerea)and Colletotrichum capsica(C.cinerea).Compounds 7d,7l,7t and 7x were identified as the most promoting candidates,and their anti-F.graminearum EC50 values were as low as 0.56,0.47,0.46 and 0.49μg/mL,respectively,presenting the similar antifungal activity as that of the commonly used fungicide carbendazim(0.43μg/mL).The 3D-QSAR models were built for a systematic structure-activity relationship profile to explore more potent pyrazole-4-carbohydrazides as novel fungicides.Molecular docking of 7d,7l and 7r with SDH was performed to reveal the binding modes in active pocket and analyze the interactions between the molecules and the SDH protein.     

Synthesis and Properties of Pentafluorosulfanyl Group (SF5)-Containing Meta-Diamide Insecticides

Herein, we describe novel pentafluorosulfanyl (SF₅) group-containing meta-diamide insecticides. For the facile preparation of the SF₅-based compounds 4a–d, practical synthetic methods were applied. Among newly synthesized compounds, 3-benzamido-N-(2,6-dimethyl-4-(pentafluoro-λ⁶-sulfanyl)phenyl)-2-fluorobenzamide 4d showed (i) a high insecticidal activity, (ii) an excellent selectivity to insects, and (iii) good levels of water solubility and log P values. In this study, we demonstrated that the pentafluorosulfanyl moiety could serve as an attractive functionality for the discovery of a new scope of crop-protecting agents.     

KAIF4化合物的合成

KAIF₄ has been prepared by different procedures and product characterized by XRD and SEM methods.It is indicated that step by step reaction of solution synthesis in which pH = 4 and vaporized at 100℃ was the best procedure for preparing a high purity, thin and particle uniform product.     

2-甲基-4-甲氧基苯基苯胺的合成

邻硝基甲苯在甲醇、乙酸和硫酸混合溶液中, 在Pt/C的催化下发生氢化和Bamberger重排生成2-甲基-4-甲氧基苯胺. 后者在Pd/C的存在下以苯酚为反应介质与环已酮缩合生成2-甲基-4-甲氧基苯基苯胺, 反应总产率63.0%. 文中给出了产物与中间产物的核磁共振氢谱和质谱, 同时讨论了影响反应的因素.     

分散固相萃取/超高效液相色谱-串联质谱法测定食用菌中19种杀虫剂、杀菌剂及其代谢物

建立了测定食用菌(蘑菇、木耳、银耳等)中19种杀虫剂、杀菌剂及其代谢物残留量的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。样品采用乙腈均质振荡提取,盐析和无水硫酸镁除水,经N-丙基乙二胺(PSA)和十八烷基硅烷键合硅胶(C₁₈)净化后,以乙腈和水为流动相,经XR-ODS色谱柱(2.0 mm×100 mm×2.2μm)分离后,在多反应监测(MRM)模式下,以目标化合物的保留时间和碎片离子丰度比定性,采用基质匹配标准曲线外标法进行定量分析。结果表明,19种待测物在一定质量浓度范围内线性关系良好(r²>0.998 0),检出限为0.2～0.6μg/kg,定量下限为0.5～2.0μg/kg。在1倍、2倍和10倍定量下限加标水平下,19种待测物的平均回收率为83.1%～106%,相对标准偏差(RSD,n=6)为5.0%～12%。该方法具有操作简单、快速、灵敏、准确的特点,适用于食用菌中19种杀虫剂、杀菌剂及其代谢物残留的快速检测。     

Synthesis of 4a-, 4e-phenyladamantanones and 2,4-o-benzenoadamantane by π-route

The acid catalysed reaction of 4-oxa-homoadamantan-5-one ($\text{1}$) with benzene yielded a mixture of 4^a-phenyladamantan-2-one ($\text{7}$), the equatorial isomer' ($\text{8}$) and 2-phenyl-2,4-o- benzenoadamantane ($\text{9}$) A plausible reaction pathway for the occurrence of $\text{9}$. is put forward. The structure of $\text{9}$, was deduced from spectroscopic data and reaction of the proposed intermediate 2,4^a-diphenyladamantan-2-ol ($\text{11}$) with acid. 2,4-o-Ben-zenoadamantane ($\text{16}$) is prepared likewise.     

Synthesis of the sulfones of leukotriene C4, D4, and E4

A simple one-step preparation of the sulfones of Leukotriene C₄, D₄ and E₄ has been developed by the direct oxidation of the parent compounds. An alternative synthesis of these sulfones has also been carried out by reduction of an acetylenic precursor.     

模板法制备聚苯乙烯/聚4-乙烯基吡啶功能微球

以工业化的聚苯乙烯中空微球为模板,利用种子乳液法合成了粒径均一的功能化中空聚苯乙烯/聚4-乙烯基吡啶(PS/P4VP)微球,改变制备条件可以控制功能基团4-乙烯基吡啶(4-VP)在聚苯乙烯微球表面的分布.合成的微球在水和有机溶剂如二氯甲烷、乙醇、乙腈等中有良好的分散性,并能促进油水体系混溶.     

Novel Analogues of a-Terthienyl, Thienyl 1, 3, 4-Thia(oxa)diazoles as Potential Photoactivated Insecticides: Synthesis and Bioactivity

a-Terthienyl (aT) is a phototoxic compound originated from the marigold Tagetes eretra1. The aT and its analogues have been widely used for photodynamic killing of insects, in photodynamic therapy for dermatophytes, and in human immunodeficiency virus (HIV)2. The phototoxicity of aT and its derivatives are attributed to their triplet states that easily generate a reactive oxygen species (ROS). Many of the biomolecules and enzymes are targets of these ROS, such as DNA in vitro and in v…     

Synthesis and crystal structure of SnSbBiS4

The quaternary compound SnSbBiS₄ formed in the SnSb₂S₄-SnBi₂S₄ system at the ratio SnSb₂S₄: SnBi₂S₄ = 1: 1 was studied for the first time by various physicochemical methods over a wide temperature interval. Single crystals of SnSbBiS₄ were prepared by chemical transport. The unit cell parameters of SnSbBiS₄, which crystallized in the hexagonal system (a = 15.52 ?, c = 3.81 ?), were determined.