甲基

The α-monobromination of 2-pentone,4-methyl acetophenone,4-methoxyacetophenone,6-methoxy-2-acetylnaphthane,2,2,5,5-tetramethyl-3-hexanone,cyclooctanone,cyclododecanone with respectively,were studied.

研究了离子液体三溴化1-丁基-3-甲基咪唑[Br3]对2-戊酮、4-甲基苯乙酮、4-甲氧基苯乙酮、6-甲氧基-2-乙酰基萘、2，2，5，5-4-甲基-3-己酮、环辛酮、环十二酮、丁醛等羰基化合物的α-溴化反应。

With heated water for extraction, DMSO,HMDS and C3H9 CLSI as derived reagent, the content of monose in Acanthopanax Senticosus tea is determined by capillary chromatography.

采用沸水提取，二甲基亚砜溶解，六甲基二硅氨烷和三甲基氯硅烷为衍生试剂，用毛细管气相色谱法测定了五加参茶中的糖含量，共测出6种单糖。

Can induce the reaction of cleavage H atom from methyl on the ring of deactivated toluenes,such as nitrotoluene. The carbanions caused by base are the very important reaction intermediums, which determined the reaction rate and reaction effect.

该反应体系中，NaOH的加入对此催化反应起着相当关键的作用，研究表明强碱也能像温度一样促进苯环卜甲基的摘氢速度，使底物形成相应的硝基苯甲基阴离子，稳定的硝基苯甲基阴离子是氧化反应进行的重要中间体。

Nornicotine is produced by the N-demethylation of nicotine during the post-harvest treatment of tobacco leaves.Nornicotine in tobacco serves as the precursor in synthesis of the well-characterized carcinogen N'-nitrosonornicotine, one of the tobacco-specific nitrosamines, and consequently damages the health of tobacco smokers and passive smokers.

烟叶的采收后处理和加工过程中，大量的尼古丁经去甲基化作用生成了去甲基尼古丁，后者是烟草特有的亚硝胺类(tobacco-specific nitrosamines， TSNAs)致癌物——亚硝基去甲基尼古丁(nitrosonornicotine， NNN)的前体，与人类健康息息相关。

The fact that the compound, 2-methyl-2-di- methylaminomethyl-5--n-pentylidenecyclo- pentanone hydrochloride (T60) possessed little anticancer activity indicated that the Mannich bases that could formed a methylene group were necessary for anticancer activity.

当环戊酮环上的Mannich碱侧链位置上引入取代基时，抗癌活性显著降低，如化合物2-甲基-2-二甲胺甲基-5--亚戊基环戊酮盐酸盐（T60）几乎无抗癌活性。这说明Mannich碱能形成亚甲基是这类化合物产生抗癌活性所必不可少的条件。

Methyl-1, 2, 3-triazol-4-carbaldehyde was synthesized through 6 steps from propargyl alcohol, and investigated the reaction of 1-phenyl-4-methyliminometyltriazole rearranging into 1-methyl-4-phenyliminometyltriazole.

并对其中1-苯基-4-亚胺甲基-1，2，3-二氮唑经开链中间体，热异构为1-甲基-4-亚胺甲基-1，2，3-三氮唑的反应进行了考察。

Methods 4-Methylacetophenone was used as starting material to give 2-(4-methylphenyl) propionitrile via reduction, chlorination and cyanation. 2-(4-Bromomethylpheny1) propionic acid obtained by hydrolysis and bromination of compound Ⅲ could further provided loxoprofen sodium through four steps.

以4-甲基苯乙酮为原料，经还原、氯化、氰化得到2-（4-甲基）苯基丙腈，然后经水解、溴化得到关键中间体2-（4-溴甲基）苯基丙酸，该中间体再经过4步反应可制得洛索洛芬钠。

A new photochromic organic compound of thiosemicarbazone, 4-( p -bromo-α-methylaminothiocarbonyl hydrazonobenzal)-2,5-dihydro-3-methyl-5-oxo-1-phenyl pyrazole, was synthesized and characterized by elemental analyses, IR, 1H NMR spectra, and X-ray single-crystal diffraction analysis.

文章合成了一个新的有机化合物1-苯基-3-甲基-4-对溴苯亚甲基-吡唑啉酮-5 缩甲基氨基硫脲(1)，并分别用元素分析、红外光谱、氢核磁共振及X-射线单晶衍射对化合物的结构进行了确证和表征。

The functions and interactions of DNA methylation regulating factors, the establishment, mantainace and removement mechanisms of DNA methylations are reviewed in this paper.

DNA转葡糖基酶有去甲基化活性从而减轻基因沉默。文章综述了以上植物DNA甲基化调控因子的生物学功能及其之间的相互作用和近年来的研究进展，以更好的理解DNA甲基化的建立、保持和去除的机制。

The six kinds of nanoparticles water dispersion were as follows:rotenone/carboxymethyl chitosan-grafted-ricinoleic acid(Rot/CMC-g-RA), azadirachtin/carboxymethyl chitosan-grafted-ricinoleic acid(Aza/CMC-g-RA),capsaicin/ carboxymethyl chitosan-grafted-ricinoleic acid(Cap/CMC-g-RA),rotenone/ricinoleic acid sodium,capsaicin/ricinoleic acid sodium,azadirachtin/ricinoleic acid sodium.

分别为：鱼藤酮/羧甲基壳聚糖接技蓖麻油酸共聚物(Rot/CMC-g-RA)、辣椒碱/羧甲基壳聚糖接技蓖麻油酸共聚物(Cap/CMC-g-RA)和印楝素/羧甲基壳聚糖接技蓖麻油酸共聚物(Aza/CMC-g-RA)纳米粒子水分散制剂，以及鱼藤酮/蓖麻油酸钠、辣椒碱/蓖麻油酸钠和印楝素/蓖麻油酸钠纳米粒子水分散微乳液。

Now, however, all children continue in "comprehensive" schools, and the eleven-plus determines which courses of study the child will follow.

然而现在，所有的孩子都要在综合学校继续学习，所以这次考试只是决定他们将要学习哪些课程。

Cultivatable land , and led to a general recognition that development must not be carried at the cost of agriculture .

城区的迅速扩大在很多情况下侵占了宝贵的可耕地，使人们普遍认识到发展不能以牺牲农业为代价。