Author/Authors :
Lin, Pen-Yuan College of Pharmacy - Taipei Medical University , Chen, Fu-An Department of Pharmacy and Master Program - Tajen University , Wu, An-Bang College of Pharmacy - Taipei Medical University , Chao, Su-Hui College of Pharmacy - Taipei Medical University , Peng, Yu-Tang College of Pharmacy - Taipei Medical University , Lee, Vickie M.-H. College of Pharmacy - Taipei Medical University , Chen, Chau-Yang College of Pharmacy - Taipei Medical University
Abstract :
In a photochemical chamber, a sample of 27.9 mM indomethacin (IN) in methanol was exposed to a Philips 400-W UV lamp for 5 days in normal atmosphere. Four photoproducts were separated using high-performance liquid chromatography, and their structures were elucidated by various spectroscopic methods, including liquid chromatography–electrospray ionization–mass spectrometry. A reaction scheme of IN in methanol is proposed: The photochemical reaction routes occur mainly via esterification and decarboxylation, followed by oxidation with singlet oxygen to produce an aldehyde. A β-hydroxy-γ-lactone was also formed through a photochemical [2 + 2] cycloaddition, and its structure was confirmed by single-crystal X-ray diffraction.
Keywords :
Indomethacin , Photoproduct , LC–ESI–MS , β-Hydroxy-γ-lactone
