The development of novel near-infrared (NIR) tetraarylazadipyrromethene fluorescent dyes

Abstract

Novel structures of an near-infrared (NIR) tetraarylazadipyrromethene (aza-BODIPY) series have been prepared. We designed the core structure containing two amido groups at the para-position of the aromatic rings. The amido group was incorporated to secure insensitivity to pH and to ensure a bathochromic shift to the NIR region. Forty members of aza-BODIPY compounds were synthesized by substitution of the acetyl group with commercial amines on the alpha bromide. The physicochemical properties and photostability were investigated and the fluorescence emission maxima (745~755 nm) were found to be in the near infrared (NIR) range of fluorescence. © 2013 by the authors; licensee MDPI, Basel, Switzerland.