83768-92-7Relevant academic research and scientific papers
Evaluation of the enantiomeric resolution of 7,8-dihydroxy-7,8-dihydrobenzo[a]-pyrene and its 6-fluoro and 6-bromo derivatives on polysaccharide-derived stationary phases
Zajc, Barbara,Grahek, Rok,Kocijan, Andrej,Lakshman, Mahesh K.,Kosmrlj, Janez,Lah, Jure
, p. 3291 - 3294 (2007/10/03)
The enantiomeric resolution and the elution order of (±)-trans-7,8-dihydrodiols of benzo[a]pyrene and its 6-fluoro and 6-bromo derivatives were analyzed on three polysaccharide-based columns: Daicel Chiralcel CA-I (cellulose triacetate), OF, and OG [cellu
Synthesis of (±)-trans-7,8-dihydrodiol of 6-fluoro-benzo[a]pyrene via hydroxyl-directed regioselective functionalization of substituted pyrene
Zajc, Barbara
, p. 1902 - 1907 (2007/10/03)
Synthesis of (±)-trans-7,8-dihydroxy-6-fluoro-7,8- dihydrobenzo[a]pyrene, the metabolite from 6-fluoro-benzo[a]pyrene, is described. Position 6 of 7,8,9,10-tetrahydrobenzo[a]pyren-7-ol (1) was functionalized by bromination with N-bromosaccharin. Regioselectivity in the bromination is thought to derive from a substrate-reagent hydrogen bond. NMR evidence is offered to support this model. The 6-bromo derivative 2 was subjected to dehydration followed by bromine-lithium exchange. Quenching the lithio intermediate with NFSi afforded the 6-fluoro derivative 4. Prevost reaction on the 7,8 double bond resulted in the trans dibenzoate 5 (established by comparison to a cis derivative prepared by osmium tetroxide cis dihydroxylation). Introduction of the 9,10 double bond by a bromination- dehydrobromination procedure, followed by hydrolysis, gave racemic trans- 7,8-dihydrodiol 7. Resolution of the enantiomers was achieved by chiral HPLC, and the absolute configurations of the early and late eluting isomers were determined through CD spectroscopy by comparison with the metabolically obtained (7R,8R)-dihydrodiol.
