• Javor Mitkov Medical University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry, 2 Dunav Street, 1000 Sofia, Bulgaria
  • Maya Georgieva Medical University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry, 2 Dunav Street, 1000 Sofia, Bulgaria
  • Alexander Zlatkov Medical University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry, 2 Dunav Street, 1000 Sofia, Bulgaria
Keywords: caffeine-8-thioglycolic acid amides, stability, RP-HPLC


This study evaluates a series of caffeine-8-thioglycolic acid amides that were synthesized in the study, for signs of possible degradation. The chemical stability of the test compounds was examined under different conditions of pH and temperature over time. A modified reversed phase-high-performance liquid chromatography method was applied to determine stability and identify possible degradation products. The study identified a new product from oxidative destruction of the test compound through controlled synthesis.


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