Photooxidation of Some Pharmaceutical Drugs by Singlet Molecular Oxygen.

Objective: Photooxidation of pharmaceutical drugs like benzyl penicillin and streptomycin by singlet molecular oxygen, both of which are antibacterial and antibiotic drugs. Methods: Methylene blue was added to the drug solutions and then irradiated with a light source and air was continuously bubbled in the reaction mixture. Effect of various factors like triplet energy of sensitizer, nature of solvent and singlet molecular oxygen scavenger on the yield of photoproduct was also observed. Results: After completion of photooxidation reaction, photoproduct was isolated and characterized by physical, chemical and spectral data. A tentative mechanism for the photooxidation has been proposed involving singlet molecular oxygen as an oxidizing species. Conclusion: The results of this study demonstrate that benzyl penicillin and streptomycin could efficiently photooxidized by singlet molecular oxygen. [ABSTRACT FROM AUTHOR]