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1 INTRODUCTION Substituted 1,2,4-triazines represent an important class of nitrogen-containing heterocycles. The 1,2, 4-triazine core is a versatile synthetic platform to access a wide range of condensed heterocyclic ring systems via intramolecular Diels-Alder reactions with a vast array of dienophiles[1~5]. In addition, 1,2, 4-triazines have been associated with diverse activi- ties such as antihypertension and inhibition of pla- telets[6] and antiinflammatory[7], and been a key com- po… 相似文献
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The title compound, ethyl 5-amino-1-[(5'-methyl-1'-t-butyl-4'-pyrazolyl)carbonyl] -3-methylthio-1H-pyrazole-4-carboxylate 5, has been synthesized by the treatment of 4 with ethyl 2-cyano-3,3-dimethylthioacrylate, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P21/c with a = 12.194(4), b = 12.909(4), c = 11.607(4) (A), β= 90.183(5)°, V = 1827.2(10) (A)3, Mr = 365.45, Z = 4, Dc = 1.328 g/cm3, μ = 0.203 mm-1, F(000) = 776, R = 0.0586 and wR = 0.1558. Preliminary bioassays indicated that the title compound shows fungicidal and plant growth regulation activities. 相似文献
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建立了同时检测化妆品中溴酸盐和碘酸盐的离子色谱-柱后衍生紫外检测器定量分析方法。样品用水提取,经RP柱净化,采用IonPac AS11-HC色谱柱分离,以EG40自动淋洗液发生器生成的KOH为淋洗液梯度洗脱,溴化钾、亚硝酸钠为衍生试剂,二极管阵列检测器检测,外标法定量。结果表明:该方法在2.0~1 000 mg/kg范围内线性关系良好(r≥0.999 8);加标回收率为84%~99%;相对标准偏差小于2%。方法简单、快速、选择性强,可用于化妆品中碘酸盐和溴酸盐的测定。 相似文献
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本文以实验课教学为例就如何培养学生能力进行了探讨;从实验教材的处理和实验课的指导两个方面入手,注重培养学生的观察与分析能力、理论联系实际的能力和解决实际问题的能力,拓宽学生思维,夯实基本功。 相似文献
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Synthesis and Crystal Structure of 3-Phenyi- 6-(4-methylphenyi)-1,2,4-triazolo[4,3-b]-1,2,4-triazine
1 INTRODUCTION The fused heterocycles bearing 1,2,4-triazine have attracted considerable attention in recent years owing to their biological and pharmaceutical activi- ties[1~3]. The 1,2,4-triazine core is a versatile synthe- tic platform to access a wide range of condensed heterocyclic ring systems via inter- and intramolecu- lar Diels-Alder reaction with a vast array of dieno- philes[4~6]. IBD (iodobenzene diacetate) is commer- cially available and used as benign non-metallic oxidant… 相似文献
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高航王啸姜菲王勍勍史洁 《化学分析计量》2023,(1):65-68
采用双氧水-硝酸-氢氟酸的消解体系,利用双氧水在低酸度下的强氧化性,使硫化矿物样品消解完全,优化了消解试剂用量等条件,结合电感耦合等离子质谱法建立了测定硫化矿物中锗量的分析方法。使用Rh作为内标校正基体效应和基线漂移,矫正曲线相关系数不小于0.999,方法检出限为0.006 mg/kg,测定结果的相对标准偏差不大于1.0%(n=6),对国家标准样品GBW 07168(GSO-7)、GBW 07163(GSO-2)及GBW 07165(GSO-4)中锗进行分析,测定结果与推荐值相符。该方法适用于硫化矿物样品中锗的测定。 相似文献