ated ▁to ▁ 2 H - inden - 1 - one ▁( 3 ) ▁using ▁the ▁re agent ▁tri eth yl am ine . ▁Ben zo [ c ] flu oren one - 9 ▁( 4 ) ▁is ▁generated ▁by ▁self - cond ens ation ▁of ▁ 2 H - inden - 1 - one , ▁when ▁he ated . ▁The ▁final ▁step ▁is ▁reduction ▁of ▁this ▁comp ound ▁with ▁hyd raz ine ▁hyd rate , ▁generating ▁ben zo [ c ] flu or ene ▁( 5 ). ▁ ▁Met abol ism ▁In ▁general ▁PA H ▁car cin ogen esis ▁involves ▁activation ▁by ▁the ▁en zym e ▁P - 4 5 0 ▁to ▁di ol ▁epo x ide ▁met abol ites ▁with ▁an ▁epo x ide ▁ring ▁in ▁the ▁bay ▁or ▁f j ord ▁region . ▁These ▁di ol ▁epo x ide ▁met abol ites ▁are ▁re active ▁and ▁capable ▁of ▁forming ▁DNA ▁ad duct s ▁( see ▁the ▁adjacent ▁image ). ▁While ▁ben zo [ c ] flu or ene ▁does ▁not ▁have ▁a ▁bay ▁or ▁f j ord ▁region ▁it ▁does ▁under go ▁a ▁similar ▁transformation ▁with ▁a ▁pseudo - bay ▁region ▁that ▁react s ▁instead . ▁The ▁type ▁of ▁cy to chrome ▁P ▁ 4 5 0 ▁involved ▁is ▁thought ▁to ▁be ▁C Y P 1 A 1 . ▁ ▁The ▁bi otr ans formation ▁is ▁dep icted ▁in ▁the ▁image ▁below . ▁First ▁ben zo [ c ] flu or ene ▁( 1 ) ▁is ▁transformed ▁into ▁trans -