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1.
混合含氟对甲苄醇类菊酯的合成及其杀虫活性   总被引:1,自引:0,他引:1  
杜劲梅  陈震  邹新琢 《有机化学》2004,24(9):1122-1124
报道了4种混合含氟对甲苄醇类拟除虫菊酯的新化合物,即三氟甲基氯菊酸、(±)-cis-二氯菊酸、(±)-trans-二氯菊酸、( )-trans-第一菊酸的含氟对甲苄酯的合成.生物活性测试的结果表明这些化合物对淡色库蚊四龄孑孓显示出较高的杀虫活性.  相似文献   

2.
张秋仙  陈震  邹新琢 《有机化学》2005,25(8):991-993
>报道了第二菊酸及其2(3)-氟-4-甲氧甲基苄酯和2(3)-氟-4-甲基苄酯的合成, 生物活性测试的结果表明这两种新化合物对淡色库蚊四龄孑孓显示出较高的杀虫活性.  相似文献   

3.
陈庆云  陈建国 《化学学报》1988,46(3):252-257
2-三氟甲基-3-氧杂-八氟己酸烯丙酯或2,5-二(三氟甲基)-3,6-二氧杂-十二氟壬酸烯丙酯可在钯的作用下产生相应的全氟碳负离子. 这些碳负离子能够质子化或者对取代苯甲酰氯发生亲核进攻, 后者为芳基氟烷基酮的合成提供了一条简捷途径. 另一方面,上述含氟酸的甲酯和取代苯甲酰氯在钯的作用下同样能发生反应而生成相应的芳基氟烷基酮.  相似文献   

4.
从β-羟基酸酯脱水制备α,β-不饱和酸酯的方法中经常伴有β,γ-不饱和酸酯的生成.与此相反,烷氧羰基亚甲基三苯基胂与脂族酮反应,生成纯的α,β-不饱和酸酯.后一反应的产物经核磁共振谱证明系顺、反异构体的混合物.甲氧羰基亚甲基三苯基胂经热裂可得反式丁烯二酸二甲酯和环丙烷1,2,3-三羧酸三甲酯.  相似文献   

5.
光学活性甲苄菊酯的合成及其结构与活性关系的研究   总被引:4,自引:0,他引:4  
本文改进了Goffinet方法,完成了(±)-trans菊酸的拆分;改进了Campbel?方法,只用一种拆分剂(奎宁)完成了对(±)-cis菊酸的拆分。用IR、~1HNMR、旋光度测定等方法确定了各甲苄菊酯光学异构体的结构。生物试验表明结构与活性有如下关系:1,各异构体中以1R-酯的杀虫活性为高,尤其(-)-(1R,3R)-trans甲苄菊酯对全部测试昆虫均显示较高的杀虫活性;2,昆虫不同,各异构体的活性次序也略有差异。  相似文献   

6.
甲氟膦酸异丙酯(GB)、甲氟膦酸特己酯(GD)、S-(2-二异丙基氨乙基)甲基硫赶膦酸乙酯(VX)等有机膦酸酯类化合物是毒性大、作用快的致死性化学战剂,而且会严重污染环境(水、泥土、粮食等),对人类和牲畜的生存构成巨大威胁.由于该类化合物在一定条件下易降解,因此对原型化合物及其降解产物的分析鉴定是确定是否被该类化合物污染的最重要指证.本文建立了水中GB等3个原型化合物和其相对应的降解产物甲基异丙氧基膦酸(IMPA)、甲基特乙氧基膦酸(PMPA)、甲基乙氧基膦酸(EMPA)以及它们的二级降解产物甲基磷酸(MPA)的分析鉴定方法.  相似文献   

7.
1引言毕富春等曾报道二氯菊酸-1-氰基-2-甲基-2-戊烯醇酯的气相色谱分离,但使用的样品是二氯菊酸-1-氰基-2-甲基-2-成烯醇酯的各个异构体的混合物,而且未加详细讨论。年文在合成光学活性二氯菊酯-(±)-1-氰基2-甲基-2-戊烯酸酯和(-)-1-氰基-2-甲基-2-戊烯醇的基础上,对它们的气相色谱行为进行了研究。其中顺式-(-)二组菊酸和顺式-(+)-二氯菊酸的(±)-1-氰基-2-甲基-2-戊烯酸酯的两个异构体在两种固定液上都得到很好的分离。很难两个异构体的峰面积的比值可以求得手性氰醇的%e.e.值。2…  相似文献   

8.
陈阳  水声霞  方向  吴范宏 《有机化学》2008,28(12):2023-2038
β-烷氧乙烯基三氟甲基酮类化合物作为一类典型的含氟砌块, 被广泛地应用于含氟有机化合物的合成中. 综述了近年来此类含氟砌块的研究进展, 特别是在合成各种含氟杂环化合物中的应用.  相似文献   

9.
以单甲氧基聚乙二醇(mPEG)和Fmoc-Lys(Boc)-OH(1)为主要原料,经过羧基苄酯化、侧链Boc脱除、ε-氨基丁二酸酐修饰得到功能化的赖氨酸化合物N-α-芴甲氧羰基-N-ε-(γ-氧代丁酸)-L-赖氨酸苄酯(4);1和4分别与mPEG在偶联剂D IC/HOB t的作用下联接,最终分别实现了赖氨酸主链和侧链的mPEG定点修饰,合成了新型的N-α-芴甲氧羰基-N-ε-(γ-氧代丁酸聚乙二醇酯)-L-赖氨酸苄酯(5,总收率52.6%)和N-ε-叔丁氧羰基-N-α-芴甲氧羰基-L-赖氨酸聚乙二醇酯(6,收率93.7%),其结构经1H NMR,IR和MS表征。  相似文献   

10.
以4-羟基苯硫酚和氯苄为原料、三乙胺为缚酸剂,制备了4-苄硫基苯酚;4-苄硫基苯酚在甲苯溶液中,经硫酸二甲酯甲基化制备了(4-羟基苯基)甲基苄基硫鎓硫酸盐;室温甲醇溶剂中,与六氟锑酸钠离子进行交换合成了目的产物(4-羟基苯基)甲基苄基硫鎓六氟锑酸盐。通过紫外光谱和核磁共振测定,对产物进行了结构鉴定。总收率大于75%。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

17.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

18.
潘素娟  全灿  周俊波 《化学通报》2014,77(12):1165-1170
测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。  相似文献   

19.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

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