3-Chloro-4-(trifluoromethoxy)b

Analysis of 2,4-Dichlorophenoxyacetic Acid and 2-Methyl-4-Chloro-Phenoxyacetic Acid in Human Urine

Two methods for the quantitative analysis of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) in urine are reported. Hydrochloric acid, sodium chloride, and internal standards (2,3-dichlorophenoxyacetic

Quantitation of Cocaine, Benzoylecgonine, Ecgonine Methyl Ester, and Cocaethylene in Urine and Blood Using Gas Chromatography-Mass Spectrometry (GC-MS

under the stream of nitrogen. The residue is incubated with pentafluoropropionic acid anhydride and pentafluoropropanol to form pentafluoropropionyl derivatives of ecgonine methyl ester and benzoylecgonine. Cocaine and cocaethylene are refractory to derivatization

Enzymes Acting on d-Amino Acid Containing Peptides

aminopeptidase and endopeptidase activities. The enzyme was active toward (d -Phe) n , Boc-(d -Phe) n , (d -Phe) n methyl ester, d -Phe-NH2 , Boc-(d -Phe) n methyl ester, and Boc-(d -Phe) n tert -butyl ester, but not toward (d -Ala) n (n = 2–4), (d