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Several strategies are examined and compared for the synthesis of the stable adducts formed by the o-quinone metabolites of carcinogenic polycyclic aromatic hydrocarbons (PAHs) with 2'-deoxyribonucleosides. The copper-mediated method is very useful for the synthesis of [super 13]C- or [super 15]N-labeled analogues and nonformation of bis-adducts as secondary products.

Results reveal that the three redox-active polycyclic aromatic hydrocarbon o-quinones tested irreversibly inhibit the catalytic fragment of protein kinase C by affecting cellular signaling via suppression of the enzyme isoforms activity. Data indicate that the inhibition is mediated by quinone interaction with the catalytic domain of the enzyme.

Research has been conducted on 7H-benzo[c]fluorene, a tar component producing DNA-bound adducts in mouse lung. The synthesis of the 7H-benzo[c]fluorene's active metabolites indicate that diol epoxide derivatives are the carcinogenic metabolites that bind to DNA in mouse lung.

Research has been conducted on the polycyclic aromatic hydrocarbons. These hydrocarbons have been metabolized to trans-dihydrodiols proximate carcinogens by human epoxide hydrolase and CYP1A1 and the results are discussed.

Research has been conducted on nonalternant polyarenes. The generation and NMR studies of persistent arenium ions from methylene-bridged polycyclic aromatic hydrocarbons are discussed.

Research describes new synthetic routes for preparing oxidized carcinogenic metabolites of polycyclic aromatic hydrocarbon of benzo[s]picene benzo[rst]pentaphene, and dibenzo[b,def]chrysene. The reactions involve double Suzuki coupling and reductive cyclization.

The terminal ring bis(dihydrodiol) derivatives of dibenz(a,j)anthracene and benzo(c)chrysene, as well as a number of higher oxidized derivatives of dibenz(a,j)anthracene, were conveniently synthesized. A key step of the synthetic route is double oxidative photocyclization of tetramethoxy-substituted diolefins. An alternative synthesis, which involves the reaction of the lithium salt of 1,4-dimethoxy-1,4-cyclohexadiene with 1,3-bis(iodoethyl)benzene to afford a bis-alkylated diketone which goes through cyclization to 3,11-diketododecahydrodibenz(a,j)anthracene, produced several higher oxidized derivatives of dibenz(a,j)anthracene.

The unsymmetrical 3,4,8,9-bis(dihydrodiol) and the 10- and 11-phenolic trans-3,4- dihydrodiols of dibenz(a,j)anthracene were efficiently synthesized. The synthetic approach involves as key steps the asymmetric dihydroxylation of a stilbene precursor using a Sharpless catalyst and intramolecular cyclodehydrobromination catalyzed by Pd(PPh3)2Cl2. Good yields were obtained in all 13 steps of the synthesis of 3,4,8,9-bis(dihydrodiol) except one, with the overall yield placed at 17%.

Research was conducted to study the expression and characterization of recombinant human dihydrodiol dehydrogenase (DD) isoforms. Several cDNAs were isolated from hepatoma cells to determine the identity of the encoded recombinant proteins by functional assays. Results showed that human liver is characterized by multiple aldo-keto reductases which influence polycyclic aromatic hydrocarbon activation. They also indicated that the DD isoforms oxidize the the major stereoisomer.

Benzo(s)picene is a potential carcinogen because it contains two fjord regions and polyarenes containing this region are among the most potent hydrocarbons causing cancer. The analysis of the carcinogenesis of this substance will be greatly aided with a method to synthesize benzo(s)picene derivatives. A synthetic protocol for trans-3,4-trans-9,10-tetrahydroxy-3,4,9,10-tetrahydro benzo(s)picene derivatives and their epoxide derivatives is presented.

A C-6 protonated chrysenium ion was synthesized from the CO-protonation of 6-acetylchrisene. Nuclear magnetic resonance analysis of the resulting chrysenium cations, CO-protonated 6-acetylchrysene and methanochrysenium ions indicated the presence of long range C-H couplings and spectral variations that were induced by variations in the halogen substituents. Furthermore, the presence of halogen substituents in the C-6 carbon unit did not alter the mode of charge delocalization in the resulting arenium ions.

Benzo[a]pyrene-7,8-dione (BPQ) is the product of the oxidation of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene in rat hepatocytes. Isolation of hepatocytes and disposition studies revealed that only a small amount of DNA was incorporated into DNA in the BPQ-DNA adducts. The radioactivity bound to the DNA was 30%. Inhibitors of dihydrodiol dehydrogenase prevented the formation of the superoxide anion radical, indicating that formation of reactive oxygen species leads to DNA fragmentation. An Ames test with Salmonella typhimurium strains showed that BPQ is a direct-acting mutagen.

The carcinogen, 7,12-dimethylbenz(a)anthracene-syn-diol epoxide (syn-DMBADE) preferentially binds to adenine and guanine amino acids of the 12, 13, and 61 codons in the human H-ras gene. Mutations produced in mice treated with DMBADE is due to the formation of DMBADE adducts with DNA. The UvrABC nuclease cleaves the syn-DMBADE-DNA complex in a sequence independent manner and allows the determination of the syn-DMBADE's binding specificity DNA. The cleavage is mainly at the 5' and 3' bases of the syn-DMBADE-DNA adduct.

The mutagenicity and specificity of the deoxyadenosine (dAdo) deoxyguanosine (dGuo) adducts derived from (+)anti-dibenz[a,j]anthracene-3,4diol 1,2 epoxide site-specifically placed in the M13mp7L2 replication vector were studied. Results showed that both dAdo and dGuo adducts effectively inhibited the action of DNA polymerases. In E. coli strains JM103 and JM103 uvrA6 cells, trans-N2-dGuo and trans-N6-dAdo adducts were noted to lower plaque yields. The dAdo adduct was also shown to trigger A to T transversions and dGuo induced G to T transversions.

Diastereomeric fjord-region amino triol derivatives of benzo[g]chrysene can suitably be synthesized by reacting the amino of polycyclic aromatic hydrocarbon (PAH) diol epoxides with purine base substrates. The PAH substrate is covalently attached to the exocyclic amino group of deoxyadenosine or deoxyguanosine. The presence of all amino triol isomers allows the synthesis of PAH-dA and -dG.

Two novel methods have been developed for the conversion of fjord region anti- and syn-diol epoxide metabolites to amino triols used as primary intermediates for the preparation of benzo[g]chrysene oligonucleotide adducts. The first method involves initial synthesis of the primary intermediate 12-hydroxybenzo[g]chrysene which is changed into trans-11,12-dihydroxy-11,12-dihydrobenzo[g]chrysene in two steps. In the second method 1,2-diarylethylene undergoes oxidative photocyclization to form a dihydrodiol moiety.

A novel synthesis strategy has been developed that is not as limited as the direct synthesis method and so allows for the large scale production of carcinogenic polycyclic aromatic hydrocarbon (PAH) oligonucleotide adducts. This method may allow for a better understanding of PAH carcinogenesis while also enabling the synthesis of many site-specifically alkylated adducts with a PAH moiety at any preselected base site. The key step of the process involves a PAH amino derivative coupled to an appropriately protected halopurine derivative.

The anti-diol epoxide derivatives of the methylene-bridged polycyclic aromatic hydrocarbon 4H-cyclopenta(def)chrysene in the bridge- and non-bridge-substituted rings were synthesized using a novel technique to handle the methylene group. The syn-diol epoxide derivative in the non-bridge-substituted ring was also synthesized. The oxidized metabolites in the D-ring are prepared through a process of oxidative photocyclization of an o-dimethoxy-substituted derivative. The locked structure of the bridge-substituted anti-diol epoxide derivative is able to retain its conformation in spite of the strained structure.

Two-dimensional nuclear magnetic resonance molecular mechanics studies were conducted on the (-)-trans-anti-[MC]dG adduct 1 positioned opposite dC in the same DNA sequence 2 used in three previous structural studies of three stereospecific benzo[a]pyrenyl [BP]dG duplex adducts. Results revealed several similarities between the structures of the (-)-trans-anti-[MC]dGdC 11-mer duplex and analogous benzo[a]-pyrenyl(-)-trans-anti-[BP]dGdC 11-mer duplex. In addition, DNA bending was linked with wedging of the methyl group of 5-methylchrysene to the 3'-side of the modification site.

Benzopyrene dihydroxy tetrahydrobenzopyrene metabolite possesses binding properties and is not involved in carcinogenesis. It forms adducts in the non-bay-region diol epoxide of Chinese hamster ovary cells. The cells are mutagenic to some extent, when compared to the cells formed by carcinogenic isomeric diol epoxide. The BPDE-III reaction with DNA enables the isolation and characterization of the three adducts.

Two dimensional NMR methods, together with energy minimization computations, were used to examine the solution structure of (+)-trans-anti-(BPh)dA adduct located opposite the dT in the sequence context d(C5-(BPh)A6-C7)-d-(G16-T17-G18) at the 11-mer duplex level. The (BPh)dA dT base pair was not terminated when the covalently bound benzo (c) phenanthrenyl intercalated to the 5'-part of the (Bph)dA adduct region.

Nitrated polycyclic fluoranthenes are analyzed by nuclear Overhauser effects, COSY and LRCOSY spectra to prepare eight mononitro products and determine their properties. DEWAR-PI molecular orbital measurements are used to make certain assumptions which tally with the regions of nitro replacement of the polycyclic fluoranthenes. The DEWAR-PI technique can be employed to precisely predict the favored interaction domain of polycyclic fluoranthenes.

An investigation of the synthesis of many methylene-bridged polycyclic hydrocarbon, involved the synthesis of 13H-dibenz (bc,l) aceanthrylene and the synthesis of previously unidentified bridged polyaseues 12H-benzo(b)cyclopenta(def)chrysene, 13H-cyclopenta(rst)pentaphene and 6H-cyclopenta(ghi)picene. Chemical or catalytic techniques of dehydrogenation to prepare 4H-benzo(c)cyclopenta(mmo)chrysene from its hexahydro precusor were unsuccessful.

Synthesis procedures for the trans 3,4-dihydrodiol and 11-methyl derivatives as well as the syn- and anti-diol epoxides of these derivatives of the potent environmental carcinogen cyclopenta(a)phenantrene are presented. Cyclopenta(a)phenantrenes are formed from sterols through pyrolysis or microbial dehydrogenation. The trans-3,4-dihydrodiol metabolite of the parent hydrocarbon interacts with DNA producing the carcinogenic effect.

A synthesis procedure for the trans-3,4-dihydrodiol derivative of 15,16-dihydrocyclopenta(a)phenantrene-17-one is presented. Although the related isomeric diol epoxide derivatives were also synthesized, they were too unstable to allow purification. The 3,4-dihydodiol derivative was shown by previous research to cause the tumorigenesis attributed to cyclopental(a)phenantrene, a sterol metabolite resulting from pyrolysis or microbial dehydrogenation.

The synthesis of bridge ketone and alcohol derivatives of methylene-bridged polycyclic aromatic hydrocarbons (PAHs) provides the material for a study of their potential mutagenicity and carcinogenicity. The oxidation of bridged PAHs is readily accomplished by treating them with butyllithium and reacting their anions with molecular oxygen. Their reaction mechanism involves proton abstraction by the peroxy anion from the intermediate's benzylic carbon, thus forming a carbonyl. The alcohols are obtained in 75-95% yields by reduction of the ketones with sodium borohydride.

Four methylene-bridged polycyclic aromatic hydrocarbons undergo electrophilic bromination and formylation with high regioselectivity. The substitution sites of 11H-benz(bc)aceanthrylene, 4H-cyclopenta(def)chrysene and 13H-dibenz(bc,l)aceanthrylene all agree with molecular orbital calculations. However, 4H-benzo(b)cyclopenta(mno)chrysene undergoes substitution at C-6 instead of C-5 as predicted. Additionally, since methyl derivatives of these PAHs are known to be carcinogenic, the bridged aryl aldehydes are methylated to allow a study of their bioactivity.

A study was conducted to characterize the synthesis of the carcinogenic anti-diol epoxide metabolite of 5-methylchrysene, a carcinogen present in cigarette smoke. A synthetic route was obtained from the oxidation of 1,3-dimethylnapthalene with ceric ammonium nitrate. Results indicated the need for a more convenient synthetic approach in characterizing the metabolite. Findings also suggested that the synthetic approach can be extended for the synthesis of analogous dihydro diol and diol epoxide metabolites.