title: endo-1,4,5,6,7,7-hexachlorobicyclo[2.2.1]hept-5-ene-2-carboxylic acid, a superior resolving agent for the high-performance liquid chromatographic separation of enantiomers of hydroxylated derivatives of two azaaromatic hydrocarbons.
abstract: The high-performance liquid chromatographic (HPLC) separation of enantiomers of oxide and hydroxy derivatives of dibenz[a,j]acridine and 7-methylbenz[c]acridine was investigated on a chiral stationary phase chromatography column using commercially available columns. In most cases either poor or no separation of enantiomers was achieved. Normal-phase separation of diastereoisomeric ester derivatives of the hydroxy compounds, prepared from commercially available (-)-menthoxyacetic acid or (+)-alpha-methoxy-alpha-(trifluoromethyl)phenylacetic acid, was investigated. No separation of the diastereoisomeric esters of trans-3,4-dihydroxy-3,4-dihydrodibenz[a,j]acridine was observed. However, diastereoisomeric esters prepared from (+)-endo-1,4,5,6,7,7-hexachlorobicyclo[2.2.1]hept-5-ene-2-carboxyl ic acid [(+)-HCA] were easily separated. Using the three chiral acids, diastereoisomers were prepared from sixteen hydroxy derivatives of dibenz[a,j]acridine and 7-methylbenz[c]acridine. (+)-HCA esters gave good to excellent HPLC separations which were superior to those achieved using other chiral acids in most cases. The enantiomeric composition of trans-3,4-dihydroxy-3,4-dihydrodibenz[a,j]acridine formed as a major rodent liver microsomal metabolite of dibenz[a,j]acridine was determined using (+)-HCA.
authors.affiliation: Department of Pharmacy, University of Sydney, N.S.W., Australia.
authors.forename: C C
authors.initials: CC
authors.lastname: Duke
authors.forename: G M
authors.initials: GM
authors.lastname: Holder
mesh_terms: D000215:Acylation; D001372:Aza Compounds / Q000302:isolation & purification*; D001643:Bridged Bicyclo Compounds; D002851:Chromatography, High Pressure Liquid; D006868:Hydrolysis; D006900:Hydroxylation; D007202:Indicators and Reagents; D013237:Stereoisomerism
chemical_list: D001372:Aza Compounds; D001643:Bridged Bicyclo Compounds; D007202:Indicators and Reagents; C058455:1,4,5,6,7,7-hexachlorobicyclo(2.2.1)hept-5-ene-2-carboxylic acid