Reported to be a hydrogen sulphide (H2S) fluorescent probe. Contains an acetoxymethyl ester, which enhances cell permeability and is hydrolyzed inside the cell to trap the probe. Used to visualize VEGF-induced H2S production in human umbilical vein endothelial cells (HUVECS). Excitation wavelength ~ 495 nm; emission maximum ~ 520 nm. MW (observed): 685.55.