title: Reactions of 'bay-region' and non-'bay-region' diol-epoxides of benz(a)anthracene with DNA: evidence indicating that the major products are hydrocarbon-N2-guanine adducts.
abstract: The rates of reaction and the products formed when two vicinal diol-epoxides derived from benz(a)anthracene, anti-BA-3,4-diol 1,2-oxide (t-3,r-4-dihydroxy-t-1,2-oxy-1,2,3,4-tetrahydrobenz(a) anthracene)* and anti-BA-8,9-diol 10,11-oxide (r-8,t-9-dihydroxy-t-10,11-oxy-8,9,10,11-tetrahydrobenz(a)anthracene) reacted with DNA were studied in vitro and the results were compared with those obtained in similar experiments using anti-BP-7,8-diol 9,10-oxide (r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene). The reactivities appeared to decrease in the order anti-BP-7,8-diol 9,10-oxide > anti-BA-3,4-diol 1,2-oxide > anti-BA-8,9-diol 10,11-oxide. The diol-epoxides reacted to a similar extent with single- and with double-stranded DNA but reactions with dGMP, at equivalent concentrations, were much slower than with DNA. With the diol-epoxides of benz(a)anthracene, two principal adducts were present in DNA hydrolysates and evidence was obtained, based on pK determinations before and after nitrous acid treatment, consistent with their being N2-guanine derivatives, analogous to the known DNA-reaction products of benzo(a)pyrene 7,8-diol 9,10-oxide.
authors.affiliation: Chester Beatty Research Institute, Institute of Cancer Research, Royal Cancer Hospital, Fulham Road, London SW3 6JB, UK.
authors.forename: K
authors.initials: K
authors.lastname: Hemminki
authors.forename: C S
authors.initials: CS
authors.lastname: Cooper
authors.forename: O
authors.initials: O
authors.lastname: Ribeiro
authors.forename: P L
authors.initials: PL
authors.lastname: Grover
authors.forename: P
authors.initials: P
authors.lastname: Sims
mesh_terms: D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide / Q000378:metabolism*; D001551:Benz(a)Anthracenes / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000378:metabolism*; D018736:DNA Adducts / Q000378:metabolism*; D015394:Molecular Structure
chemical_list: D001551:Benz(a)Anthracenes; D018736:DNA Adducts; C026622:8,9-dihydro-8,9-dihydroxybenzanthracene 10,11-oxide; D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide; C026832:3,4-dihydroxy-1,2-epoxy-1,2,3,4-tetrahydrobenz(a)anthracene; D004247:DNA