New derivatization reactions in pharmaceutical analysis.

Area of Science:

• Analytical Chemistry
• Organic Chemistry

Background:

• Chemical reactions are crucial for sample preparation in analytical chemistry.
• Spectrometric and chromatographic techniques require derivatization or selective modification for optimal analysis.

Purpose of the Study:

• To demonstrate the utility of chemical reactions in conjunction with spectrometric and chromatographic methods.
• To showcase specific examples of derivatization and selective reactions for enhanced analytical outcomes.

Main Methods:

• Formation of 2-nitrophenylhydrazide derivatives for carboxylic acid assay.
• Silylation and trifluoroacetylation for drug analysis via gas chromatography.
• Selective reduction of steroid ketones for IR identification.
• Epoxidation for differentiating saturated and unsaturated steroids.
• Hydrochloric acid treatment for isomeric steroid analysis.
• Difference spectrometry using hydrochloric acid.

Main Results:

• Successful derivatization enabled spectrometric determination of carboxylic acids.
• Gas chromatography analysis of drugs was improved by silylation and trifluoroacetylation.
• Selective reduction facilitated IR spectrometric identification of steroid ketones.
• Epoxidation effectively distinguished between saturated and unsaturated steroids.
• Hydrochloric acid treatment enhanced selectivity and sensitivity for isomeric steroid determination.
• Difference spectrometry provided a method for analyzing specific benzhydrol derivatives.

Conclusions:

• Chemical derivatization and selective reactions significantly improve the selectivity and sensitivity of spectrometric and chromatographic analyses.
• These chemical approaches are versatile, applicable to a wide range of analytes including organic acids, pharmaceuticals, and steroids.
• The presented methods offer robust solutions for complex analytical challenges in chemistry.