Hydroxymethoxybenzoylmethylecgonines: new metabolites of cocaine from human urine.

4'-Hydroxy-3'-methoxybenzoylecgonine methyl ester (IIIe) and 3'-hydroxy-4'-methoxybenzoylecgonine methyl ester (IIId) were identified as cocaine metabolites in the urine of an admitted habitual polydrug user. The mass spectra and relative gas-liquid chromatography retention times of these metabolites were compared with those of five synthesized hydroxymethoxycocaine positional isomers. IIIe was also identified by mass chromatography in the urine of three patients who received emergency treatment for cocaine abuse.