High-performance liquid chromatographic determination of d-/l-epinephrine enantiomer ratio in lidocaine-epinephrine local anesthetics.
A procedure for the determination of the ratio of d- to l-epinephrine in lidocaine-epinephrine local anesthetics is described. Epinephrine was isolated via Sep-Pak cartridges and derivatized with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate; the d- and l-chiral derivatives were separated and measured by high-performance liquid chromatography. About 70 samples of various dosage forms and concentrations from four manufacturers were successfully analyzed by the method.
Enantiomeric separation of d-/l-norepinephrine and -epinephrine by high-performance liquid chromatography with a beta-cyclodextrin type chiral stationary phase.
Enantiomeric separation of d-/l-norepinephrine (NE) and d-/l-epinephrine (E) was investigated with various mobile phases by high-performance liquid chromatography using a beta-cyclodextrin type chiral stationary phase as a chiral column. The mobile phase of 2.5 M phosphate buffer (pH 3.0) gave separation factors (alpha s) of 1.04 and 1.06 for NE and E, respectively.
Cyclodesulfurization Reaction of Glycosyl Thioureides
Reactions of glycosyl isothiocyanates (1a, b, c) with diamines such as o-phenylenediamine, 2, 3-diaminopyridine or 5, 6-diamino-1, 3-dimethyluracil gave the corresponding glycosyl thioureides in good yields. Glycosyl thioureides were converted into N-glycosylaminobenzimidazoles (5a, b, c), N-glycosyl-3-deazapurine (6a) or N-glycosylaminotheophyllines (7a, b, c) in excellent yields through a cyclodesulfurization reaction.