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hydroxylation Reaction Mechanism for Nitrosodimethylamine by Oxygen Atom

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Chemical Research in Chinese Universities 2011年第6期27卷 1006-1009页

作者： LI Lan LIN Xiao-yan LI Zong-he College of Sciences Shanghai Institute of Technology Shanghai 200235 P. R. China College of Chemistry Beijing Normal University Beijing 100875 P. R. China

The hydroxylation reaction mechanism of nitrosodimethylamine（NDMA） by oxygen atom was theoretically investigated at the B3LYP/6-31G＊＊ level. It has been found that the path of the oxydation of the C―H bond is easier than the path involving a Singlet/Triplet crossing. The study of the potential surface shows that both solvent effect at B3LYP/6-31G＊＊ level and different method at more credible MP2/6-311G＊＊ level in the gas phase have no effect on the hydroxylation reaction mechanism. The oxidation hydroxylation process of NDMA by O is exothermic reaction and easy to occur.

关键词： Nitrosodimethylamine(NDMA) hydroxylation B3LYP MP2

Continuous Flow Reactor for hydroxylation of Benzene to Phenol by Hydrogen Peroxide

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Chinese Journal of Chemical Physics 2012年第5期25卷 585-591,I0004页

作者： Li Zhang Hui-hui Liu Gui-ying Li Chang-wei Hu Key Laboratory of Green Chemlstry and Technology Ministry of Education College of Chemlstry Sichuan University Chengdu 610064 China

The direct hydroxylation of benzene to phenol catalyzed by activated carbon-supported Fe （Fe/AC） in acetonitrile using H2O2 as the oxidant was studied in a continuous flow reactor. Results showed that the continuous operation could obtain high phenol yield of 28.1%, coupled with the turnover frequency of 3 h^-1, and high selectivity of 98% under mild condition. The catalyst was characterized by N2 adsorption/desorption, Boehm titration, X-ray photoelectron spectra, and Fourier transform infrared spectroscopy. It was observed that iron may interact with the carboxyl group forming iron-carboxylate like species, which act as the active phase. The apparent activation energy obtained by fitting an Arrhenius model to the experimental data was 13.4 kJ/mol. The reaction order was calculated to be about i, 0.2 for benzene and 0.7 for H202.

关键词： Continuous flow reactor hydroxylation Activated carbon Iron-carboxylate Active phase Activation energy

Nanotrap-enabled quantification of KRAS-induced peptide hydroxylation in blood for cancer early detection

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Nano Research 2019年第6期12卷 1445-1452页

作者： Zaian Deng Zhen Zhao Bo Ning Jeffery Basilio Karen Mann Jie Fu Yajun Gu Yuanqing Ye Xifeng Wu Jia Fan Paul Chiao Tony Hu College of Health Science and Environmental Engineering Shenzhen Technology UniversityShenzhen 518118 China School of Biological and Health Systems Engineering Virginia G. Piper Biodesign Center for Personalized DiagnosticsThe Biodesign InstituteArizona State UniversityTempeArizona 85287USA Department of Nanomedicine Houston Methodist Research InstituteHoustonTexas 77030USA Pathology and Laboratory Medicine Weill Cornell Medical CollegeNew York New York 10065USA Center for Molecular Design and Biomimetics The Biodesign InstituteArizona State UniversityTempeArizona 85287USA Department of Laboratory Medicine Clinical CenterNational Institutes of HealthBethesdaMaryland 20892USA Department of Molecular Oncology H. Lee Moffitt Cancer CenterTampaFlorida 33612USA Department of Molecular and Cellular Oncology The University of Texas MD Anderson Cancer CenterHoustonTexas 77030USA School of Medical Laboratory Tianjin Medical UniversityTianjin 300203China Department of Epidemiology The University of Texas MD Anderson Cancer CenterHoustonTexas 77030USA

Circulating peptide is a potential source of biomarkers for cancer ***,the existence of large molecular weight proteins in plasma have a disastrous effect on circulating peptides isolating and ***,nanotrap fractionation following by mass spectrometry have been applied to quantify the levels of bradykinin (BK) and hydroxylated bradykinin (Hyp-BK) as a relative measure of KRAS-regulated prolyl-4-hydroxylase alpha-1 (P4HA1) which may serve as early diagnosis marker for pancreatic ductal adenocarcinoma (PDAC).We found that P4HA1 can be upregulated by KRASG12v,which is a PDAC driver mutation,using HPNE/KRAS and HPNE *** we revealed that P4HA1 is overexpressed in PDAC tumors,compared to normal and inflamed pancreatic *** interference revealed that P4HA1 activity was primarily responsible for Hyp-BK *** spectrometry analysis revealed that plasma Hyp-BK/BK ratio was higher in PDAC than pancreatitis patients and healthy controls,while the area under the receiver operating characteristic (ROC) curve (AUC) is 0.8209 (95%Cl,0.7269-0.9149).The Hyp-BK/BK association with PDAC was reproduced in another cohort,where this ratio was found to increase with advancing tumor *** novel findings paved the way for wider applications of Nanotrap coupled mass spectrometry as a powerful tool for revealing biosignatures from plasma.

关键词： nanotrap hydroxylation level bradykinin pancreatic ductal adenocarcinoma

Controlled growth of uniform two-dimensional ZnO overlayers on Au(111)and surface hydroxylation

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Nano Research 2019年第9期12卷 2348-2354页

作者： Hao Wu Qiang Fu Yifan Li Yi Cui Rui Wang Nan Su Le Lin Aiyi Dong Yanxiao Ning Fan Yang Xinhe Bao State Key Lab of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Department of Chemical Physics University of Science and Technology of ChinaHefei 2300263China Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China

Ultrathin ZnO nano structures prese nt in teresti ng two-dimensi on al(2D)graphene-like structure in contrast to wurtzite structure in bulk *** on Au(111)has been regarded as a well-established route to the 2D ZnO layers while controlled growth of uniform ZnO nano structures remains as a challe ***,reactive deposition of Zn in O3 and NO2 was employed,which is investigated by sea nning tunneling microscopy and X-ray photoelectr on spectroscopy(XPS).We dem on strate that uniform ZnO mono layer nanoislands and films can be obtained on Au(111)using O3 and uniform ZnO bilayer nanoislands and films form on Au(111)using NO2,*** of atomic oxyge n overlayers on Au(111)via exposure to O3 is critical to the formatio n of uniform ZnO mono layer nano structures *** ambient pressure XPS studies revealed that n early full hydroxy lati on occurs on mono layer ZnO structures upon exposure to near ambient pressure water vapor or atomic hydrogen species,while partial surface hydroxylation happens on bilayer ZnO under the same gaseous exposure conditions.

关键词： graphene-like ZnO two-dimensional materials hydroxylation near ambient pressure X-ray photoelectron spectroscopy(NAP-XPS) seanning tunneling microscopy(STM)

Efficient stereoselective hydroxylation of deoxycholic acid by the robust whole-cell cytochrome P450 CYP107D1 biocatalyst

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Synthetic and Systems Biotechnology 2023年第4期8卷 741-748页

作者： Chixiang Sun Baodong Hu Yanchun Li Zhimeng Wu Jingwen Zhou Jianghua Li Jian Chen Guocheng Du Xinrui Zhao Science Center for Future Foods Jiangnan University1800 Lihu RoadWuxiJiangsu214122China Key Laboratory of Industrial Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology Jiangnan University1800 Lihu RoadWuxiJiangsu214122China Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology Jiangnan University1800 Lihu RoadWuxiJiangsu214122China Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationJiangnan University1800 Lihu RoadWuxiJiangsu214122China

Deoxycholic acid(DCA)has been authorized by the Federal Drug Agency for cosmetic reduction of redundant submental *** hydroxylated product(6β-OH DCA)was developed to improve the solubility and pharmaceutic properties of DCA for further ***,a combinatorial catalytic strategy was applied to construct a powerful Cytochrome P450 biocatalyst(CYP107D1,OleP)to convert DCA to 6β-OH ***,the weak expression of OleP was significantly improved using pRSFDuet-1 plasmid in the *** C41(DE3)***,the supply of heme was enhanced by the moderate overexpression of crucial genes in the heme biosynthetic *** addition,a new biosensor was developed to select the appropriate redox ***,a cost-effective whole-cell catalytic system was constructed,resulting in the highest reported conversion rate of 6β-OH DCA(from 4.8%to 99.1%).The combinatorial catalytic strategies applied in this study provide an efficient method to synthesize high-value-added hydroxylated compounds by P450s.

关键词： OleP Deoxycholic acid hydroxylation Redox partners Whole-cell catalysis

Pyridine-H_5PMo_(10)V_2O_(40) hybrid catalysts for liquid-phase hydroxylation of benzene to phenol with molecular oxygen

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Science China Chemistry 2009年第8期52卷 1264-1269页

作者： GE HanQing1,LENG Yan1,ZHANG FuMin1,PIAO JiaRui2,ZHOU ChangJiang1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical Engineering,College of Chemistry and Chemical Engineering,Nanjing University of Technology,Nanjing 210009,China 2 Petrochemical Research Institute,PetroChina Company Ltd.,Beijing 100083,China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing China Petrochemical Research Institute PetroChina Company Ltd. Beijing China

Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2O40,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by *** various catalysts,Py3PMo10V2O40 exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic acid,molecular oxygen and ascorbic acid used as the solvent,oxidant and reducing reagent,*** of reaction temperature,reaction time,oxygen pressure,amount of ascorbic acid and catalyst on yield of phenol were investigated to obtain the optimal reaction conditions for phenol *** can greatly promote the catalytic activity of the Py-free catalyst(H5PMo10V2O40),mostly because the organic π electrons in the hybrid catalyst may extend their conjugation to the inorganic framework of heteropoly acid and dramatically modify the redox properties,at the same time,pyridine adsorbed on heteropoly acids can promote the effect of "pseudo-liquid phase",thus accounting for the enhancement of phenol yield.

关键词： hydroxylation benzene organic/inorganic hybrid catalyst phenol heteropoly acid pyridine

Effect of Supercritical Fluids on the Biological Activity of Absidia coerulea for the hydroxylation of Reichsterin's Substance Acetate

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Chinese Chemical Letters 2005年第1期16卷 107-110页

作者： XiuFengLIU HuiMingZHU TuanWeiZHANG BaoQuanZHANG SchoolofChemicalEngineeringandTechnology TianjinUniversityTianjin300072

The viability and biological activity of Absidia coerulea in compressed or supercritical CO2 and C2H4 were studied. The specific activity of Absidia coerulea in 7.5MPa CO2 and C2H4 at 306K can reach to 23% and 75% respectively, leading to the feasibility of using supercritical C2H4 as an alternative to the organic solvent in the hydroxylation of Reichsterin’s substance acetate.

关键词： Absidia coerulea hydroxylation hydrocortisone supercritical fluids.

Synthesis of Rare Earth Based Modenite and Study on Its Performance for Catalyzing Phenol hydroxylation Reaction

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China Petroleum Processing & Petrochemical Technology 2011年第1期13卷 45-51页

作者： Chen Xiaodong Qi Xiaolan Zhang Jingchang College of Science Beijing University of Chemical Technology Beijing 100029 Shanghai Research Institute of Petrochemical Technology Shanghai 201208

La or Ce-containing mordenite samples were synthesized from an amine-free fluorine-containing system with a quite broad range of raw materials *** cerous nitrate was used in place of lanthanum nitrate as the starting material for synthesis of the zeolite,the formation of quartz could be *** is the necessary starting material for synthesis of the rare earth-containing modernite,which features good activity for catalyzing phenol hydroxylation reaction with a less tar formation and a higher ratio of ortho-hydroxyphenol/*** activity of Ce-containing modernite is apparently higher than that of La-containing *** mordenite sample with high cerium content can give a higher phenol conversion coupled with a 200% increase in hydroquinone selectivity,resulting in an apparent reduction in para-benzoquinone *** phenol conversion increases in big chunks with an increasing reaction temperature,leading to an obvious reduction in para-benzoquinone selectivity along with an increasing decline ratio of ortho/para-positioned hydroxyphenol *** appropriate hydroxylation reaction time is in the range of 4-6 hours.

关键词： rare earth elements modernite phenol hydroxylation dihydroxybenzene

A facile and efficient method for hydroxylation of azabenzanthrone compounds

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Chinese Chemical Letters 2011年第1期22卷 41-44页

作者： Fang Xian Ning Xiang Weng Shi Liang Huang Li Jun Gu Zhi Shu Huang Lian Quan Gu School of Pharmaceutical sciences Sun Yat-Sen University Guangzhou 51006 China

A novel and facile method of introducing 4-hydroxyl group into the aromatic ring of azabenzanthrone compounds was carried out by reacting azabenzanthrone compounds with hydrazine hydrate or hydroxylamine hydrochloride and sodium hydroxide in diethylene glycol （DEG） solvent. The mechanism of reaction may involve an amino intermediate and follow a hydroxyl substitution process.

关键词： Azabenzanthrone hydroxylation Hydrazine hydrate Hydroxylamine hydrochloride Sodium hydroxide