Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1994-12-22
pubmed:abstractText
Dibenzo[a,l]pyrene (DB[a,l]P) is the most potent carcinogen among polycyclic aromatic hydrocarbons. Because the fjord-region diolepoxide (DE) pathway is one of the mechanisms of activation, (+/)-trans-DB[a,l]P-11,12-dihydrodiol, (+/-)-anti-DB[a,l]PDE and (+/-)-syn-DB[a,l]PDE were synthesized. The key intermediate for these syntheses, 12-methoxy-DB[a,l]P, was successfully obtained by cyclization of 6-(3-methoxybenzyl)benzanthrone with methanesulfonic acid, which in turn was prepared by 1,4 conjugate addition of 3-methoxybenzyl magnesium bromide to benzanthrone. The presence of the DB[a,l]P nucleus in the dihydrodiolepoxides and diolepoxides was proven by conversion of 12-methoxyDB[a,l]P into the parent compound in several steps. The tumor-initiating activity of the two diolepoxides in mouse skin was compared to that of DB[a,l]P-11,12-dihydrodiol and the parent DB[a,l]P. Groups of 24 8 week old female SENCAR mice were topically initiated with 12, 4 or 1.33 nmol of compound in 100 microliters of acetone. Starting 1 week later, promotion with 12-O-tetradecanoylphorbol-13-acetate (1.62 nmol in 100 microliters acetone) was begun and continued twice weekly for 30 weeks. At the 12, 4 and 1.33 nmol doses, anti-DB[a,l]PDE induced 2.0, 0.7 and 0.7 tumors per mouse (t/m) respectively, whereas syn-DB[a,l]PDE induced 1.8, 1.5 and 1.8 t/m. At the same three doses, DB[a,l]P-11,12-dihydrodiol induced 4.6, 4.3 and 2.8 t/m, and DB[a,l]P resulted in 9.3, 7.1 and 5.2 t/m. These results confirm that DB[a,l]P is more potent than its 11,12-dihydrodiol and show that the two diolepoxides are less tumorigenic than their precursors. At the medium and low doses, syn-DB[a,l]PDE is more tumorigenic than its congener anti-DB[a,l]PDE.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0143-3334
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2455-60
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Synthesis and tumor-initiating activity in mouse skin of dibenzo[a,l]pyrene syn- and anti-fjord-region diolepoxides.
pubmed:affiliation
Marion Merrell Dow Inc., Cincinnati, OH 45215.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.