羟基

1H NMR spectroscopic analysis of aromatic protons combined with theoretical analysis of molecular structures proved the existence of two rotational isomers at 300 K, as well as a rapid interconversion equilibrium at 330 K for both compounds Ⅰ and Ⅱ. However, only one conformer exists for compound Ⅲ and puerarin containing 7-phenolic hydroxyl instead of propyl in A-ring as the case of compounds Ⅰ and Ⅱ. Based on UV-Visible absorption data of neutral and basic solutions, and on the density function calculations, the 7-phenolic hydroxyl group in A-ring was found to be more acidic than the 4'-phenolic hydroxyl group in B-ring. The mechanism of derivation reaction and the structure-reactivity relationship of puerarin as an antioxidant were further discussed.

其中7-丙基葛根素Ⅱ属于新型取代衍生物；变温1H NMR和理论计算结果表明，在300 K时，葛根素和4'-丙基葛根素以单一构型存在；而7，4'-二丙基葛根素和7-丙基葛根素则存在两种核磁可分辨的旋转异构体，当温度升至330 K时，两种异构体可以相互转化；通过对比分析葛根素及其衍生物脱质子产物的紫外可见吸收光谱并结合理论计算，确定了A环上7位酚羟基比B环上4'位酚羟基先脱去质子，并由此进一步阐明了葛根素衍生化反应机理以及在抗氧化作用中可能的活性位点和结构活性关系。

Coralline hydroxyapatite; Hydroxyapatites ; Bone grafts ; Recombinant human bone morphogenetic protein2

珊瑚羟基磷灰石；羟基磷灰石类；骨移植材料；基因重组人骨形成蛋白－2

The inner diameter of b-CD cone is 0.65nm and the extra is 1.53nm. The hydroxyl groups of C(6)(the sixth carbon atoms of glucose unit and the same as follows) are located on the smaller opening of the cone with counterclockwise direction, while the hydroxyl groups of C(2) and C(3) are located on the larger opening of the cone with reverse direction.

环糊精外型是内空的圆台形，其中β-环糊精内空腔的直径为0.65 nm，外径为1.53nm.C(6)(葡萄糖单元上第六个碳，下同)上的羟基位于空腔的细口端指向逆时针方向，C(2)、C(3)上的羟基位于空腔的宽口端指向相反的方向。

The quantitative analysis of hydroxyl radical can be done through the determination of the peak current and the fluorescence intensity.

通过测定峰电流和荧光强度的变化可以间接测定羟基自由基以及抗氧化剂对羟基自由基的清除能力。

Through using Mythylene DinitrAmine as rude product, the knowledge of its reaction properties in different phases have been increased, Through using Mythylene BisAcetAmide as rude product, intermediates which include 1,3-Diacetyl -4,5-dihydroxy -1,3-diazacyclopentane and 1,3-Diacetyl- 4,5-diacetoxy-l,3-diaza cyclopentane have been obtained. 2,4,6,8-tetracetyl- 2,4,6,8-tetraaza bicyclo[3,3,0]octane which can be used to produce Bicyclo-HMX by nitrolysis was also produced. Through using Mythylene BisFormAmide as rude product, intermediates which include 1,3-Diformyl-4,5-dihydroxy- 1,3-diazacyclopentane and 1,3-Diformyl- 4,5-diacetoxy-l,3-diazacyclopentane have been abtained.

以亚甲基二硝胺为初始原料，加深了对亚甲基二硝胺在不同反应相反应特征的认识；以亚甲基二乙酰胺为初始原料，制备了中间体1，3-二乙酰基-4，5-二羟基-1，3-二氮杂环戊烷和1，3-二乙酰基-4，5-二乙酰氧基-1，3-二氮杂环戊烷，最终制备了可被直接硝解为双环HMX的2，4，6，8-四乙酰基-2，4，6，8-四氮杂双环[3，3，0]辛烷；以亚甲基二甲酰胺为初始原料，制备了中间体1，3-二甲酰基-4，5-二羟基-1，3-二氮杂环戊烷和1，3-二甲酰基-4，5-二乙酰氧基-1，3-二氮杂环戊烷。

The cis novel bisoxazoline ligands L1-L4 have been synthesized through the treatment of new cis dihydroxy diamide with p-toluenesulfonyl chloride in the presence of catalytic quantity of 4--pyridine, and the cis dihydroxy diamide could be achieved from the condensation of the amino alcohols and cis cyclopropane dicarbonyl chloride prepared via oxidation and halogenation from cis-2,2-dimethyl-3-formylcyclopropanecarboxylate with DCC.

我们以蒈醛酸内酯为起始原料，经过氧化反应、酰氯化反应得到顺式环丙烷二酰氯，然后在二环己基碳二亚胺的催化下与相应的氨基醇反应合成了顺式二羟基酰胺，再用对甲苯磺酰氯将羟基活化，最后在二甲氨基吡啶的催化下关环合成顺式双噁唑啉配体L1～L4。

The computer simulation showed that the hydroxyl group at β site of adsorbent with dimethylamine ligand could form H bond with endotoxin, as a result an eight-membered ring was formed.

模拟结果显示，以二甲胺为配体的吸附剂，当β位存在羟基时，此羟基可与内毒素分子间形成氢键，并形成一个八元环的稳定结构。

The computer simulation showed that the hydroxyl group at β site of adsorbent with dimethylamine ligand could form H bond with endotoxin, as a result an eightmembered ring was formed.

模拟结果显示，以二甲胺为配体的吸附剂，当β位存在羟基时，此羟基可与内毒素分子间形成氢键，并形成一个八元环的稳定结构。

Under some conditions, the synergistic extraction behavior with 2-hydroxyl-4-sec-octyl- diphenylamine and trioctylphousphine oxide has also been studied.

研究了2-羟基-4-仲辛基-二苯甲酮肟在氯仿中萃取钯的行为及2-羟基-4-仲辛基-二苯甲酮肟与三辛基氧化膦协同萃取钯的行为。

Because the recovery of 5-hydroxytryptophan from plant is low, and the technics is complex, the plant source is limited. Electroanalysis synthesize method has been used to transform tryptophan to 5-hydroxytryptophan.

由于5-羟基色氨酸从植物中的提取收率较低，工艺复杂，植物来源有限，通过查阅文献资料，采用电解合成法在催化剂存在下，使色氨酸部分转化成为5-羟基色氨酸。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。