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Science China Chemistry 1989年第7期32卷 776-790页

作者：戴乾圜钟儒刚 Center for Chemistry & bioengineering of Cancer Beijing Polytechnic University

In this paper, it is evidenced by the quantitative structu re-carcinogenic activity relation-ship (QSCAR) and the pattern recognition treatment of N-nitroso compounds (NNC) that thekey step of carcinogenesis induced by NNC is the cross-linking on the complementary basepair of DNA, through the bifunctional alkylation between α-carbon and another carbonwithin the same chain. The alkylation by the α-carbon atom is through the diazonium salt,but that by the atom other than the α-position is through the active ester formed from thehydroxylated metabolite of the chain. Therefore, the alkylation by the β-position of NNC,or by its γ-position under suitable conditions, of which the distances from the α-positionboth approach 2. 80-3. 00 A, would be the most favourable positions along with the α-posi-tion for the cross-linking to occur between the complementary base pairs of DNA, whichwill yield the carcinogenic activity of NNC. The above conception of bifunctional alkyla-tion can reduce the QSCAR of NNC to a reasonable structure-chemical reactivity relationshipunder the complex biological conditions, and is the successful extension of the Di-regiontheory to the carcinogenesis mechanism of the important NNC series. In the light of theabove viewpoint, for 153 NNCs including the nitrosamines and nitrosamides which havebeen tested reliably with animals, the correct discrimination ratio by quantitative patternrecognition according to carcinogenic activity indexes divided into 5 degrees comes up to ashigh as 97%.

关键词： N-nitroso compounds Di-region theory pattern recognition chemical carcinogenesis structure-carcinogenic activity relationship

Exploring binding mode for styrylquinoline HIV-1 integrase inhibitors using comparative molecular field analysis and docking studies

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Acta Pharmacologica Sinica 2004年第7期25卷 104-112页

作者： Xiao-hui MA, Xiao-yi ZHANG, Jian-jun TAN, Wei-zu CHEN, Cun-xin WANG2 college of LifeScience and bioengineering, beijing University of Technology, beijing 100022, China college of Life Science and bioengineering Beijing University of Technology Beijing 100022 China

AIM: To understand pharmacophore properties of styrylquinoline derivatives and to design inhibitors of HIV-1 integrase. METHODS: Comparative molecular field analysis (CoMFA) was performed to analyze three-dimen- sional quantitative structure-activity relationship (3D-QSAR) of styrylquinoline derivatives. Thirty-eight compounds were randomly divided into a training set of 28 compounds and a test set of 10 compounds. The stability of 3D- QSAR models was proved by the analysis of cross-validated and non-cross-validated methods. Moreover, the binding mode of these compounds and integrase was constructed by AutoDock program. RESULTS: The CoMFA model of the training compounds was reasonably predicted with cross-validated coefficient (q2) and conventional (r2) values (up to 0.696 and 0.754). Then the model was validated by the test set. The resulting CoMFA maps visualized structural requirements for the biological activity of these inhibitors. Docking results showed that a carboxyl group at C-7 and a hydroxyl group at C-8 in the quinoline subunit, bound closely to the divalent metal cofactor (Mg2+) around the integrase catalytic site. Moreover, there is a linear correlation between the binding energy of the inhibitors with integrase and their inhibitory effect. CONCLUSIONS: The present study indicated that the CoMFA model together with docking results could give us helpful hints for drug design as well as interpre- tation of the binding affinity between these inhibitors and integrase.

关键词： HIV integrase inhibitors quinolines comparative molecular field analysis AutoDock

Theoretical Studies on the Isomerization of Peroxynitrite to Nitrate Mediated by Peroxynitrous Acid

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Chinese Journal of Structural Chemistry 2008年第2期27卷 171-176页

作者： LIU Yong-Dong ZHONG Ru-Gang college of Life Science ＆ bioengineering Beijing University of Technology Beijing 100022 China

The conversion of peroxynitrite （ONOO-） to nitrate （NO3-） mediated by peroxynitrous acid （ONOOH） has been investigated at the CCSD/6-311G（d）//B3LYP/6-31 1＋G（d,p） level. Two kinds of pathways for the title reaction were found. The results show that the energy barrier of isomerization through pathway 1 is around 25 kcal/mol in the gas phase. This value is significantly lower than that of isomerization without any catalysts. Thus, it indicates that ONOOH definitely makes the conversion from ONOO- to NO3- feasible. Although pathway 2 does not decrease the energy barrier of this isomerization, peroxynitric acid （O2NOOH） was obtained; moreover, this is a new pathway for this formation. In view of the results that peroxynitrate anion can decompose into nitrite and dioxygen, we conclude that our results are consistent with the experimental observation that nitrate, nitrite, and dioxygen are the main final products of the decay of peroxynitrite around pH 7.

关键词： peroxynitrite peroxynitrous acid isomerization DFT

Synthesis and Crystal Structure of 7-Acetamido-5-chloro-8-(p-methyl-oxybenzenesulfonyloxy)-2-styrylquinoline

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Chinese Journal of Structural Chemistry 2007年第6期26卷 669-673页

作者：李雪梅曾程初焦自国阎红钟儒刚 college of Life Science & bioengineering Beijing University of Technology

The title compound 7-acetamido-5-chloro-8-（p-methyloxybenzenesulfonyloxy）-2- styrylquinoline 4 （C26H21ClN2O5S, Mr = 508.96） has been synthesized and characterized by 1HNMR, IR, ESI-MS and single-crystal X-ray diffraction techniques. The crystal belongs to orthorhombic, space group Pca21, with a = 7.920（3）, b = 10.672（5）, c = 28.008（12） A, V = 2367.3（17） A^3, Z = 4, Dc = 1.425 g/cm^3, μ = 0.290 mm^-1, F（000） = 1056, R = 0.0323 and wR = 0.0692 for 3895 unique reflections with 3127 observed ones （Ⅰ〉 2σ（Ⅰ））. X-ray analysis reveals that the styrylquinoline subunit adopts a coplanar conformation, where the benzene ring and quinoline are in trans configuration.

关键词： styrylquinoline derivatives synthesis crystal structure

MNDO research on alkylation of DNA bases by the non-α-position metabolite of 3, 5-dimethyl-N-nitrosopeperazine

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Chinese Science Bulletin 1997年第8期42卷 698-700页

作者： ZHONG Rugang and DAI QianhuanCenter for Cancer Chemistry and bioengineering, beijing polytechnic University, beijing 100022. China Center for Cancer Chemistry and bioengineering Beijing Polytechnic IJniversity Beijing China

IT is a commonly accepted concept that having formed alkyldiazonium ions after α-hydroxyla-tion,the metabolites of N-nitroso compounds(NNCs)combine with DNA and initiate *** the complex relationship between carcinoge... 详细信息

关键词： nitrosopeperazine di-region theory alkylation of DNA MNDO.

Experimental verifications on chemical carcinogenesis, a bifunctional alkvlation between DNA interstrands

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Chinese Science Bulletin 2000年第12期45卷 1075-1079页

作者： DAI Qianhuan, ZHANG Qingrong, WANG Lihui, PEI Shu, WANG Qing &QUBoCenter for Chemistry and bioengineering of Cancer, beijing polytechnic University, beijing 100022, China Center for Chemistry and bioengineering of Cancer Beijing Polytechnic University Beijing China

It is evidenced by the filter elution method that two carcinogenic aromatic hydrocarbons, benzo[a]pyrene and dibenzo[a,h]anthracene, two carcinogenic metal salts, beryllium chloride and cadmium chloride, four carcinogenic aromatic amines, 2-aminofluorene, p-naphthylamine, 4-aminobiphenyl and benzidine, can all induce DNA interstrand and DNA-protein cross-link in L12io culture. However, under the same condition, the corresponding non-carcinogenic compounds, including benzo[k]fluorancene, anthracene, magnesium chloride, zinc chloride, a-naphthylamine, 2-aminobiphenyl and m-toluidine, cannot produce any cross-link adducts. All these results are consistent with the di-region theory that carcinogens are bio-bifunctional alkylation agents. This method can also be used to discriminate carcinogens and non-carcinogens.

关键词： mechanism of chemical carcinogenesis di-region theory DNA interstrand cross-link aromatic amines poiycyclic aromatic hydrocarbons beryllium salt cadmium salt.

Practical two-dimensional correlation power analysis and its backward fault-tolerance

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Science China(Information Sciences) 2017年第6期60卷 257-259页

作者： An WANG Wenjing HU Weina TIAN Guoshuang ZHANG Liehuang ZHU School of Computer Science Beijing Institute of Technology State Key Laboratory of Cryptology The Institution of beijing Jinghang Computing Communication college of bioengineering beijing polytechnic Science and Technology on Information Assurance Laboratory

Side-channel analysis was introduced by Kocher et al.[1,2]which marked the outbreak of this new research field in the applied cryptography ***,many side-channel analysis methods have been published,for example,correla... 详细信息

关键词： DCPA In Practical two-dimensional correlation power analysis and its backward fault-tolerance CCA rate TP

Mechanism of 1,2-shift through π-complex transition state

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Science China Chemistry 2000年第6期43卷 576-586页

作者：戴乾圜周志刚张大平 Center of Chemical and bioengineering of Cancer Research Beijing Polytechnic University Beijing 100022 China

A systematic calculation of the potential curves or surfaces for 1,2-shift has been realized by using MNDO or other models in MOPAC programs. By referring to the previous author’ viewpoints, the 1,2-shift can be divided into two categories. 1,2-electron-deficient shift is that the electronic configuration of the atom which accepts the migrating group is a cation or an electron-deficient atom, and 1,2-anion shift is the one that the accepted atom of the migration group is a negative ion. In terms of the experimental facts and the calculation of the potential surfaces, in electron-deficient shift such as Beckmann or Baeyer-Villiger rearrangement, the migration occurs through a transition complex formed between the π-bond and the cation or electron-deficient migrating group, but in anion shift such as Wittig or Stevens rearrangement, the electron pair in π-orbit excites at first to π orbit, and then the migration occurs through the new formed complex between the anion migration group and the vacant π orbit. The above mechanisms explain reasonably the intramolecular properties, the configuration retentions of the migration group, and the corresponding migratory aptitudes of the two type 1, 2-shifts. The partial and less important free radical reaction of 1, 2-anion shift has been explained by the π-complex mechanism too.

关键词： 1 2-shift rearrangement MNDO potential surface π-complex Wittig rearrangement.

QUANTITATIVE EXPLANATION ON STRUCTURE-CARCINOGENIC ACTIVITY RELATIONSHIP OF AROMATIC AMINES BY DI-REGION THEORY

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Science China Chemistry 1991年第5期34卷 547-559页

作者：戴乾圜郑菁英王宗一 Center for Chemistry and bioengineering of Cancer Beijing Polytechnic University Beijing 100022. PRC

Di-region theory, the theory for the mechanism of carcinogenesis, has been extendedsuccessfully on the quantitative Structure-carcinogenic activity relationship (QSCAR) of 63aromatic amines. A quantitative equation for the QSCAR of aromatic amines has been estab-lished by the mechanism conception of the specialized di- functional alkylation between thenitrenium ion of the amino group and the epoxide of the aromatic ring. The agreementbetween calculation and experiment comes up to 98%. Thus, it can now express the puzzlingvariation of the carcinogenicity of aromatic amines, as a comprehensible structure-chemicalreactivity relationship.

关键词： aromatic amine di-region theory mechanism of carcinogenesis structure-carcinogenic activity relationship (SCAR) carcinogenesis turned on by transcription genes

Comparison of Mechanisms of N-Nitrosation and N-Nitration of Ammonia and Dimethylamine by Reactive Nitrogen Oxygen Species:A Theoretical Study

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Chinese Journal of Structural Chemistry 2010年第3期29卷 421-431页

作者：刘永东钟儒刚 college of Life Science & bioengineering Beijing University of Technology

Reactive nitrogen oxygen species（RNOS） implicate damage in biological systems,especially leading to inflammation,neurodegenerative and cardiovascular diseases,and cancer by altering the functions of biomolecules through the N-nitrosation and N-nitration *** mechanisms of N-nitrosation and N-nitration reactions of ammonia and dimethylamine by RNOS,i.e.,N2O3,N2O4,N2O5 and ONOOH,were investigated at the CBS-QB3 level of *** computational results indicate that the N-nitrosation reaction prefers a concerted mechanism,in which a H-abstraction and ON-addition occur simultaneously,whereas a stepwise mechanism（also called a free radical mechanism） is more favorable for most nitrating agents in the N-nitration reaction,where NO2 first abstracts a hydrogen atom from the nitrogen of amines and then the induced intermediate reacts with NO2 once more to form the nitration ***,the concerted pathway is still a feasible process for some nitrating agents such as *** addition,the relationship between the structures of different RNOS and their nitrosating or nitrating abilities was also investigated.

关键词： N-nitrosation N-nitration reactive nitrogen oxygen species mechanism nitrosamines