Chemiluminescent 2,6-diphenylimidazo[1,2-a]pyrazin-3(7H)-ones: a new entry to Cypridina luciferin analogues.
An investigation of the chemiluminescent properties of 2,6-diphenylimidazo[1,2-a]pyrazin-3(7H)-one derivatives (1), having substituted phenyl groups, is described. Among the derivatives 1, the 6-[4-(dimethylamino)phenyl] derivatives (1a,d-f) gave a high quantum yield (Φ(CL) ≥ 0.0025) in diglyme/acetate buffer, which is a model reaction condition for the Cypridina bioluminescence. Their efficient chemiluminescence is mainly caused by the electronic effect of the substituent at C6. In particular, the electron-donating 4-(dimethylamino)phenyl group at C6 of 1a,d-f plays an essential role in increasing the chemiexcitation efficiency (ΦS) by the charge transfer-induced luminescence (CTIL) mechanism. The results provide useful information for designing new Cypridina luciferin analogues showing efficient chemiluminescence.
Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan. hirano@pc.uec.ac.jp.
Yuki
Y
Ishii
Chihiro
C
Hayashi
Yoshihisa
Y
Suzuki
Takashi
T
Hirano
D000085:Acetates / Q000737:chemistry; D000818:Animals; D002021:Buffers; D003530:Cyprinidae; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D005026:Ethylene Glycols / Q000737:chemistry; D049408:Luminescent Agents / Q000737:chemistry*; D008163:Luminescent Measurements; D008738:Methyl Ethers / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D011719:Pyrazines / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000737:chemistry
D000085:Acetates; D002021:Buffers; D005026:Ethylene Glycols; D049408:Luminescent Agents; D008738:Methyl Ethers; D011719:Pyrazines; D012972:Sodium Hydroxide; C007391:diglyme; D004121:Dimethyl Sulfoxide