Luminescence of coelenterazine derivatives with C-8 extended electronic conjugation

Replacement of the methylene group at the C-8 position with an extended electronic conjugation is a new promising method to develop red-shifted coelenterazine derivatives. In this paper, we have described an oxygen-containing coelenterazine derivative with a significant red-shifted (63 nm) bioluminescence signal maximum relative to coelenterazine 400a (DeepBlueC (TM), 1). In cell imaging, the sulfur-containing coelenterazine derivative displayed a significantly (1.77 +/- 0.09; P <= 0.01) higher luminescence signal compared to coelenterazine 400a and the oxygen-containing coelenterazine derivative exhibited a slightly (0.74 +/- 0.08; P <= 0.05) lower luminescence signal. It is beneficial to understand further the underlying mechanisms of bioluminescence. (C) 2016 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.