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Chinese Science Bulletin 1998年第11期43卷 917-921页

作者： ZHONG Rugang ZHAO Yufen dai qianhuan Bioorganic Phosphorus Chemistry Laboratory Department of ChemistryTsinghua UniversityBeijing 100022China Center for Chemistry and Bioengineering of Cancer Research Beijing Poly technic UniversityBeijing 100022China.

N-phosphoryl-α-amino acids can react to form esters, peptides, phosphoryl ester-exchanged products and phosphoryl group migration products under mild conditions, which are very important in researches on arohebiont. It has been proposed that intramolecular mixed carboxylic-phosphoric anhydrides (IMCPAs) might be the common intermediates of the reactions, which are difficult to be experimentally observed because of their high activity. In this note, it has been revealed, by means of MNDO, that the IMCPAs are situated at the relatively minimal points of the potential surface and can form in a non-synchronous concerted reaction pathway that passes through a transition state with a hydrogen-bond-bridge structure. The results give a successful explanation to the structure and formation of IMCPAs and their ability to promote the various reactions mentioned above.

关键词： N-phosphorylamino-acid intramolecular mixed anhydride mechanism MNDO.

Carcinogenesis of asbestos switched on by inducing cross-linkage between DNA complementary pair bases

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Chinese Science Bulletin 2002年第13期47卷 1086-1091页

作者： dai qianhuan CHEN Sha LI Yingxia Center of Environmental Science Peking UniversityBeijing 100871China Center for Chemistry and Bioengineering of Cancer Beijing Polytechnic UniversityBeijing 100022China

Since the beginning of the 1980s, dai qianhuan predicted based upon his di-region theory that the carcino-genesis switched on by the so-called physical carcinogenic factors including radiation, asbestos and foreign matter implantation, is just initiated through the cross-linking between DNA complementary pair bases induced by them. In this note, it was evidenced with the DNA filter elution method that the oxygenase activated by asbestos induces the cross-linking between DNA inter-strands and DNA-protein with dosage correlation, in which over 80% of DNA inter-strand cross-link ratio account for the total cross-link ratio. Obviously, both of the cross-linkages are just induced by hydroxyl free radical, HO·, because the ferrous ion increased the cross-link ratios up to several times through Fenton reaction and vitamin C inhibited the cross-link ratios with factors of 8-9 by destroying the hydroxyl radical. Non-carcinogen but with lower free radical formation energy, pyrene, by culturing with asbestos

关键词： asbestos mechanism of carcinogenesis di-region theory hydroxyl free radical DNA interstrand cross-link Fenton reaction AM1 molecular orbital calculation.

DNA interstrand cross-link induced by estrogens as well as their complete and synergic carcinogenesis

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Chinese Science Bulletin 2000年第23期45卷 2125-2130页

作者： qianhuan dai Xin Liu Beijing Polytech Univ Ctr Chem & Bioengn Canc Res Beijing 100022 Peoples R China

The estrogens show negative activity in Ames test, but estrodiol and diethylstilbestrol in estrogens both are carcinogens based upon animal experiments and epidemiological investigation. It is concluded from the di-region theory, a mechanism conception put forward by one of the present authors, that the carcinogenesis of estrogens is switched on by the covalent cross-link between complementary DNA bases induced by them. We verified for the first time by the DNA alkaline elution method that both estrodiol and diethylstilbestrol cause covalent cross-link between DNA-protein and DNA interstrands after metabolic activation with dosage correlation, but neither the non-carcinogens cholesterol nor pyrene can lead to these sorts of cross-link in the same condition. It has been known that there is a synergetic effect between estrogen and pollution of polycyclic aromatic hydrocarbons. Although non-carcinogenic pyrene alone cannot induce cross-link, its addition with equal molar quantity to estrodiol culture

关键词： estrogen mechanism of carcinogenesis synergic carcinogenesis di-region theory DNA interstrand cross-link bi-radical.

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.

STRUCTURE PREDICTION, ENUMERATION AND WHOLESALE MOLECULAR ORBITAL CALCULATION OF POLYCYCLIC AROMATIC HYDROCARBONS

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Science in China,Ser.B 1986年第11期29卷 1133-1146页

作者：戴乾圜石冰志 Beijing Polytechnic University

Based upon our previous works, a systematic mathematical demonstration of polycyclic aromatic hydrocarbons (PAH) graphs has been carried out in this laboratory. The uniqueness of characteristic number (linear topology notation of PAH), the even number theorem for the discriminating of complete aromaticity for PAH in structure prediction and enumeration, the transformation theorem from the characteristic number to form the adjacency matrix uniquely, the diserote mathematics strategy for the programming of the automatic MO calculation to a whole class of compounds as well as the other aspects have been demonstrated in this paper. In terms of these research, the wholesale molecular orbital calculation (WMO) and the linear notation containing all the topologic information of PAH molecule have been put forward for the first time, so the first example for the structure prediction and enumeration of PAH having truly chemical significance as well as automatic, systematic MO calculation of whole compound class h

关键词： PAH ENUMERATION AND WHOLESALE MOLECULAR ORBITAL CALCULATION OF POLYCYCLIC AROMATIC HYDROCARBONS STRUCTURE PREDICTION

PM3 computation for the DNA complementary base paircross-linked by the metabolite of Benzo[a] pyrene

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Chinese Science Bulletin 1998年第2期43卷 175-175页

作者： qianhuan dai Bo Qu Rugang Zhong Dawei Zheng Center for Chemistry and Bioengineering of Cancer Beijing Polytechnic University Beijing China

Discusses PM3 computation for DNA complementary base pair cross-linked by the metabolite of Benzo[a]pyrene. Experimental procedure; Distance of positions.

关键词： base PM3 computation for the DNA complementary base paircross-linked by the metabolite of Benzo[a pyrene DNA

Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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Science China Chemistry 2006年第1期49卷 44-62页

作者： dai qianhuan1,2 1. Center of Chemistry and Bioengineering of Cancer Research, Beijing Polytechnic University (Now known as Beijing Univer-sity of Technology), Beijing 100022, China 2. Center of Environmental Sciences, Peking University, Beijing 100871, China Center of Chemistry and Bioengineering of Cancer Research Beijing Polytechnic University Beijing China Center of Environmental Sciences Peking University Beijing China

In 1979, the mechanism of chemical carcinogenesis, a challenging and difficult scientific problem pending for a number of years, was explained by dai qianhuan. The mechanism named di-region theory predicted that a carcinogen always metabolizes to form a special bi-functional alky-lating agent. This agent induces cross-linkages between the complementary base pairs in DNA and switches on initial mutageneses in genomes including point and frameshift mutations. This, in turn, induces further deep mutageneses including the production of various chimeric chromosomes, dele-tions and other aberrations found in genomes. In the end this initiates carcinogenesis of the whole cell through the reverse transcription mechanism after a lengthy incubation period. Recently, this labora-tory has verified that physical carcinogenesis, including the oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced by endogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing the formation of cross-linkages between the com-plementary base pairs in DNA. Di-region theory has now been supported by many experimental observations such as mutational spectra of various carcinogens. The potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together as genetic toxicity appears to originate almost uniformly from the cross-linking between complementary bases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms of cross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylation anticancer activity but lack genetic toxicity. The predict-able design and synthesis of a high selectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued in cancer chemotherapy, have been realized for the first time in this laboratory by inhibiting malignant and heightening benign cross-linking using the principles of di-region theory. A series of patented new anticancer platinum complexes c

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

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香紫苏醇侧链的氧化降解

有机化学 2003年第1期23卷 95-99页

作者：王文军戴乾圜陈莎中国石化北京化工研究院北京100013 北京工业大学癌化学与工程中心北京100022

研究了高锰酸钾、高硼酸钠、高碘酸钠等对香紫苏醇侧链的氧化降解 ,并通过IR ,NMR ,MS或元素分析等技术对氧化降解产物的结构进行了表征 .

关键词：侧链香紫苏醇氧化降解天然产物药物高锰酸钾高硼酸钠高碘酸钠

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龙涎香的组成及降龙涎醚的合成研究进展

有机化学 2001年第3期21卷 167-172页

作者：王文军陈莎戴乾圜北京大学环境科学中心北京100871

简要介绍了龙涎香的应用及其化学组成 ,重点介绍了以香紫苏醇为原料 ,通过不同的氧化 -还原

关键词：龙涎香降龙涎醚香紫苏醇合成动物药动物香料

GENERAL FORMULAS OF APPROXIMATE CALCULATION FOR TOTAL π-BOND ENERGIES OF ARBITRARY FUSED POLYCYCLIC AROMATIC HYDROCARBONS

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Chinese Science Bulletin 1984年第1期29卷 58-60页

作者：戴乾圜 Beijing Industrial University

At present, it is only possible to obtain the closed forms of H(?)ckel molecular orbital parameters, e.g. the coefficients of energies and orbits for some special conjugated systems, such as linear molecules, single ring molecules, polyacene series and radialene series. Thus we can obtain the other parameters including the total π-bond energies

关键词： conjugated orbital dibenzo bonds rings figures mathematics Gupta straight hydrocarbons