Development of Novel Imaging Fluorescent Agents Bearing Anti-Inflammatory Drugs: Synthesis, Structural Characterization and Evaluation of Biological Activity

Abstract

A new series of 5,6-benzocoumarin derivatives carrying anti-inflammatory drugs were synthesized via alkylamide spacers, the target to develop novel imaging fluorescent agents as useful technique to cancer early discovery. Experimentally, treatment of N-Boc-1,3-propanediamine with ethyl 5,6-benzocoumarin-3-carboxlate (III) under reflux conditions followed by hydrolyzed with CF3COOH to the corresponding primary amine (V), then treatment of derivative (V) with anti-inflammatory drugs have carboxylic group in presence of DCC (N,N'-dicyclohexylcarbodiimide) as catalyst and MeCN as solvent. The structure of the synthesized compounds was confirmed by FT-IR, NMR (1H,13C) spectral data as well as elemental analysis. The fluorescence properties study was investigated spectrophotometrically in methanol and maximum emission (λem) exhibited within range 411–436 nm, meanwhile, the quantum yields were calculated comparison to Rhodamine 6G as reference. Interestingly, the compound (III) gave a higher quantum yield (ΦF = 0.96), meanwhile, compounds (VII, VIII, IX and XI) gave reasonable quantum yields (ΦF) 0.60, 0.65, 0.78 and 0.84, respectively. All synthesized compounds were screened for their anti-AChE and antimicrobial activity. Based on the results, some of the compounds showed good activity in compared to the standard drugs.