Abstract: The aim is to provide a novel compound that can luminesce with high brightness and be used as a luminescent substrate in a firefly bioluminescence system. Provided is a heterocyclic compound, or salt thereof, represented by the following general formula (1): [R1, R2, and R3 are independently hydrogen or an alkyl group having a carbon number of 1-4, with provisos that R1 and R2 are optionally bonded to form a ring and that one of R1 and R2 is optionally bonded to Y1 to form a ring; X is S, O, NR4, or CH2, and Y1 and Y2 are independently N or CR4, where each R4 is independently hydrogen, an alkyl group having a carbon number of 1-4, an alkenyl group having a carbon number of 2-4, or an acyl group having a carbon number of 2-4; n is an integer of 0-4].

Abstract: The aim is to provide a novel compound that can luminesce with high brightness and be used as a luminescent substrate in a firefly bioluminescence system. Provided is a heterocyclic compound, or salt thereof, represented by the following general formula (1): [R1, R2, and R3 are independently hydrogen or an alkyl group having a carbon number of 1-4, with provisos that R1 and R2 are optionally bonded to form a ring and that one of R1 and R2 is optionally bonded to Y1 to form a ring; X is S, O, NR4, or CH2, and Y1 and Y2 are independently N or CR4, where each R4 is independently hydrogen, an alkyl group having a carbon number of 1-4, an alkenyl group having a carbon number of 2-4, or an acyl group having a carbon number of 2-4; n is an integer of 0-4].

Abstract: An object of the present invention to provide a firefly luciferin and firefly luciferin analog that are modified to maintain luminescent activity by luciferase in a firefly bioluminescent system. In particular, it is an object of the present invention to provide a new luminescent substrate for which the emission wavelength in a firefly bioluminescent system is shifted to a longer wavelength than that of a conventional luminescent substrate. The present invention provides a luciferin in which the benzothiazole ring moiety has been modified at the 7-position, a luciferin analog in which the benzene ring moiety has been modified at the 6-position, and a luciferin analog in which the 6-(dialkylamino)-2-naphthalenyl moiety has been modified at the 5-position.

Abstract: An object of the present invention to provide a firefly luciferin and firefly luciferin analog that are modified to maintain luminescent activity by luciferase in a firefly bioluminescent system. In particular, it is an object of the present invention to provide a new luminescent substrate for which the emission wavelength in a firefly bioluminescent system is shifted to a longer wavelength than that of a conventional luminescent substrate. The present invention provides a luciferin in which the benzothiazole ring moiety has been modified at the 7-position, a luciferin analog in which the benzene ring moiety has been modified at the 6-position, and a luciferin analog in which the 6-(dialkylamino)-2-naphthalenyl moiety has been modified at the 5-position.

Abstract: The present invention relates to a compound having a structure analogous to firefly luciferin. In particular, the invention relates to a heterocycle compound which produces a luminescence at a light wavelength different from that of firefly luciferin in nature. The present invention provides a heterocycle compound of following general formula I. In the above general formula, R1, R2 and R3 can be each independently H or C1-4-alkyl. In the above general formula, X and Y can be each independently C, N, S or O. In the above general formula, the olefin chain part expressed as “n” can be changed to desired length.

Abstract: The present invention relates to a compound having a structure analogous to firefly luciferin. In particular, the invention relates to a heterocycle compound which produces a luminescence at a light wavelength different from that of firefly luciferin in nature. The present invention provides a heterocycle compound of following general formula I. In the above general formula, R1, R2 and R3 can be each independently H or C1-4-alky. In the above general formula, X and Y can be each independently C, N, S or O. In the above general formula, the olefin chain part expressed as “n” can be changed to desired length.