Firefly luciferin

Firefly luciferin
Names
	IUPAC name (4S)-2-(6-hydroxy-1,3-benzothiazol-2-yl)-4,5-dihydrothiazole-4-carboxylic acid
	Other names D-(−)-Luciferin, beetle luciferin
Identifiers
CAS Number	2591-17-5;
3D model (JSmol)	Interactive image;
ChemSpider	4588411; 16735812 One of the other tautomeric representations;
ECHA InfoCard	100.018.166
EC Number	219-981-3;
PubChem CID	92934;
UNII	5TBB02N29K;
CompTox Dashboard (EPA)	DTXSID00894865 ;
	InChI InChI=1S/C11H8N2O3S2/c14-5-1-2-6-8(3-5)18-10(12-6)9-13-7(4-17-9)11(15)16/h1-3,7,14H,4H2,(H,15,16)/t7-/m1/s1 Key: BJGNCJDXODQBOB-SSDOTTSWSA-N; One of the other tautomeric representations: InChI=1S/C11H8N2O3S2/c14-5-1-2-6-8(3-5)18-10(12-6)9-13-7(4-17-9)11(15)16/h1-3,7,13H,4H2,(H,15,16)/b10-9+/t7-/m1/s1; InChI=1S/C11H8N2O3S2/c14-5-1-2-6-8(3-5)18-10(12-6)9-13-7(4-17-9)11(15)16/h1-3,7,14H,4H2,(H,15,16)/t7-/m1/s1;
	SMILES O=C(O)[C@@H]1/N=C(\SC1)c2sc3cc(O)ccc3n2;
Properties
Chemical formula	C11H8N2O3S2
Molar mass	280.32 g·mol−1
Appearance	Yellow Powder
UV-vis (λmax)	330 nm (neutral and somewhat acidic aqueous solutions)
Absorbance	ε330 = 18.2 mM−1 cm−1
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Firefly luciferin (also known as beetle luciferin) is the luciferin, precursor of the light-emitting compound, used for the firefly (Lampyridae), railroad worm (Phengodidae), starworm (Rhagophthalmidae), and click-beetle (Pyrophorini) bioluminescent systems. It is the substrate of firefly luciferase (EC 1.13.12.7), which is responsible for the characteristic light emission of many firefly and other insect species in the visible spectra ranging from 530 until 630 nm.

As with other luciferins, oxygen is essential for the luminescence mechanism, which involves the decomposition of a cyclic peroxide to produce excited-state molecules capable of emitting light as they relax to the ground state. Additionally, it has been found that adenosine triphosphate (ATP) and magnesium are required for light emission.