查询词典 catechol

THE FIRST TOTAL SYNTHESIS OF TAXAMAIRIN B Taxamairin B, representive of rare naturally-occuring rearrang-ed 9(10→20)-abeo-8, 11, 13-triene diterpenoids, has been firstsynthesized by a eleven-step route in an overall yield of 8.19%,starting from commercially available catechol and 1,3-cyclohexan-dione. The improved Friedel-Crafts annulation, thermodynamicallycontrolled-geminal pairing methylation, the selective oxidation ofallyl group and the selective reduction of the less-hindrancecarbon-carbon double bond are the key steps.

二。美丽红豆杉素B的全合成研究 1，美丽红豆杉素B的首次全合成以价廉，易得的邻苯二酚和1，3-环己二酮为原料，经过改良的Friedel-Crafts烷基化反应，热力学控制的α，β-不饱和酮结构的α一位双烷基化，烯丙位的选择性氧化，以及选择性还原位阻较小的碳碳双键等十一步反应，以8.19％的总收率首次完成了美丽红豆杉素B的全合成。

Projects included: Cloning and functional studies of diabetes related genes;Structural studies of thermostable Catechol 2,3-Dioxygenase by anomalous scattering; Prevention and cure, and influence factor studies of major child bearing blemish of national minority in Guizhou province.

该课题组的主要研究方向包括大规模高通量人类基因克隆及功能研究；基因芯片技术、生物信息学及功能基因组学研究；蛋白质晶体结构与功能；蛋白质热稳定机制；疾病相关基因的研究。

The recoveries of catechol and hydroquinone are found in the range of 83%-107% and 92%-100%, respectively.

该法用于测定水样中邻苯二酚和对苯二酚，回收率分别为83%~107%和92%~100%。

Catechol is one of the substrate of plant material browning.

邻苯二酚类的酚类化合物是植物材料发生褐变的主要底物。

This study is to explore the relationship between polymorphism of Catechol O-methyltransferase gene and schizophrenia.

本研究旨在探测儿茶酚氧位甲基转移酶基因多态性与精神分裂症的关系，搜寻中国汉族人精神分裂症易患性基因。

C. I. Reactive blue KN-R, Alizarin brilliant green G and Hostlam blue R could not be degraded by Zoogloea HP3. Furthermore, ABAS degradation was regressed under the exisitence of the above dyes. 1-Aminoanthraquinone-2sulfonic sodium, 1, 4-dihydroxylanthraquinone-2-sulfonic sodium, 1, 4, 5, 8tetrahydroxylanthraquinone, anthraquinone, aniline, phenol, catechol and ophthalic acid could be degraded by Zoogloea HP3. Aniline was the most degradable substrate among ABAS, aniline, phenol, catechol and o-phthalic acid. However, benzenesulfonic sodium and p-amino benzenesulfonic sodium were not degraded by it.

动胶菌HP3不能降解活性艳蓝KN-R、弱酸性绿GS及毛用活性蓝HW-R等蒽醌型染料，且染料的存在对菌体降解溴胺酸有不同程度的抑制作用；动胶菌HP3可以降解1-氨基蒽醌-2-磺酸钠、1，4-二羟基蒽醌-2-磺酸钠、1，4，5，8-四羟基蒽醌、蒽醌及苯酚、邻苯二酚、苯胺、邻苯二甲酸等苯系化合物，而不降解苯磺酸钠、对氨基苯磺酸钠；在溴胺酸、苯酚、邻苯二酚、苯胺、邻苯二甲酸中，苯胺是动胶菌HP3的天然底物。

This strain is able to degrade polycyclic aromatics such as naphthalene and biphenyl as well as monocyclic aromatics such as phenol. Under experimental conditions, strain DF51 is capable of degrading at concentrations of phenol ranging from 100 mg to 800 mg, which is catabolized mainly through the catechol 1, 2-dioxygenase pathway with a minor catechol 2, 3-dioxygenase pathway.

DF51。在本实验条件下，菌株DF51能够有效降解浓度范围为100-800mg L-1的苯酚，该菌代谢苯酚主要是通过邻苯二酚1， 2-双加氧酶催化开环途径进行，同时辅以邻苯二酚2， 3-双加氧酶催化开环，表明菌株DF51兼有混浊红球菌(Rhodoccocus opacus R7)和红球菌PNAN5Rhodoccocus sp。

A method for the determination of phenol and catechol in tobacco leaf by high performance liquid chromatography with methanol and 0.05 mol/L of monopotassium phosphate as mobile phase at a flow rate of 0.5 mL/min was described. Phenol and catechol were extracted from tobacco sample by distillation and solid phase extraction with Sep Park C 18 cartridge.

引 言挥发酚是烟草中一类重要的成分，它在烟草燃烧时直接进入烟气，大多有不好的气味，而且很难被掩盖；特别是苯酚和儿茶酚对呼吸系统有腐蚀作用和助癌作用，近年来逐渐引起了烟草化学工作者的注意〔1〕。

In the hydroxylation of phenol with H〓O〓 in the presence of Ti-ZSM-5, water is best solvent. It produces catechol and hydroquinone simultaneously, and catechol/hydroquinone ratio is approximately 0.85. The results show H〓O〓 utilization ratio increase 14%, when nonoxidizable weak acid HAc is added into the reaction system. Under the conditions of Ti-ZSM-5 as catalyst, phenol/H〓O〓 ratio being 10, a little HAc, temperature 75℃, reaction time 6h, H〓O〓 utilization ratio reaches 74. 6mo1% in the reaction.

对Ti-ZSM-5催化苯酚羟基化的研究结果表明，水是最好的溶剂，羟基化有邻、对苯二酚两种产物，并且邻苯二酚/对苯二酚摩尔比可维持在～0.85左右；向反应体系中加入非氧化性弱酸性助剂HAc时，H〓O〓有效利用率较未加入助剂时可提高14mol%；当催化剂用量为8g/100g苯酚、苯酚/H〓O〓比为10、反应温度75℃、添加少量HAc的条件下，反应6h后，H〓O〓有效利用率可达74.6mol%。

In order to check the corresponding compound at 31P NMR –45.4 ppm, stable pentacoordinate spirobicyclic 2-phenoxy-1,3-phenylene-dioxo-1,3,2-iminoacetoxyphosphoranes were synthesized through a new and efficient method whereby phosphorus pentachloride was displaced stepwise by catechol, N,O-bisamino acid and phenol, or catechol, phenol and N,O-bisamino acid, their 31P NMR chemical shifts are at about 31P NMR –45.0 ppm, the results showed that the compound 4 at 31P NMR –45.4 ppm was pentacoordinate phosphorane containing amino acid residue.

采用磷谱跟踪来研究上述成肽反应机理。例如在氮气保护下，0.1mmol O，O-亚苯基磷酰氯（1）和0.15mmol N，O-二苯丙氨酸（2）苯溶液加入0.6ml核磁管中，混合均匀，反应过程用磷谱检测。反应1分钟后，起始原料1(δp=19ppm)很快转变成N-磷酰苯丙氨酸的三甲基硅基酯（3）(δp=19.8ppm)，在8分钟内，3完全转变成苯丙氨酸磷烷4(δp =-45.4ppm)，同时出现环磷三酯（6）(δp=3.5ppm)。随着反应的进行，对应于化合物4的峰逐渐变小，而6逐渐变大。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。