CAPILLARY ZONE ELECTROPHORETIC SEPARATION OF EPIMERIC N-OXIDES OF MORPHINANE ALKALOIDS

Epimers of N-oxides of morphine, codeine, thebaine, pseudomorphine and 2,2'-biscodeine were separated by capillary zone electrophoresis in t he presence of cyclodextrins in bare silica or poly(vinyl alcohol)-coa ted capillaries in a background electrolyte with Tris-phosphate buffer , pH 2.8; diastereomers of thebaine N-oxide were separated also withou t cyclodextrins. gamma-Cyclodextrin caused the highest resolution of e pimers of morphine and codeine N-oxides, while separation of mono- and di-N-oxides of pseudomorphine and 2,2'-biscodeine without stereodiffe rentiation was best in the presence of 2,6-di-O-methyl-beta-cyclodextr in. However, addition of the former cyclodextrin resulted also in sepa ration of diastereomers of bismorphinane N-oxides. (C) 1998 Elsevier S cience B.V. All rights reserved.