Coelenterazine-h 1MG. Coelenterazine-h, CAS: 50909-86-9, Molecular Formula: C26H21N3O2, Molecular Weight: 407. 47, Purity: greater than or equal to 97%, Appearance: Yellow solid, Synonym: 2, 8-dibenzyl-6-(4-hydroxyphenyl)imidazo[1, 2-a]pyrazin-3(7H)-one 2-Deoxycoelenterazine, Size: 1MG