Chemical Information Catelog Number: F01-0153 Product Name: Pyrromethene 556 CAS Number: 121461-69-6 Molecular Formula: C14H15BF2N2O6S2Na2 Molecular Weight: 466.188 Synonyms: [[(3,5-Dimethyl-4-sulfo-1H-pyrrol-2-yl)(3,5-dimethyl-4-sulfo-2H-pyrrol-2-ylidene)methyl]methane](difluoroborane) Disodium Salt; PMPDS-BF2; EverFluor 492/515 Disulfonate Product Specification Excitation Maximum (nm): 494 Emission Maximum (nm): 517 Additional Information InChI: InChI=1S/C14H17BF2N2O6S2.2Na/c1-6-11-7(2)13(26(20,21)22)9(4)18(11)15(16,17)19-10(5)14(27(23,24)25)8(3)12(6)19;;/h1-5H3,(H,20,21,22)(H,23,24,25);;/q;2*+1/p-2 InChIKey: FBAASMARNAYERO-UHFFFAOYSA-L CanonicalSMILES: [B-]1(N2C(=C(C(=C2C(=C3[N+]1=C(C(=C3C)S(=O)(=O)[O-])C)C)C)S(=O)(=O)[O-])C)(F)F.[Na+].[Na+]Pyrromethene 556 is a green-fluorescent polar tracer dye. It is used for investigations of membrane fusion, lysis, and gap-junctional communication and to detect volume changes in cells or liposomes.