6-Chloro-1H-indol-3-yl b-D-mannopyranoside is an enzyme substrate that is used in the fluorogenic and chromogenic assays for detecting indoleamines. This compound has a conjugate, which is a fluorescent molecule that can be attached to an antibody to target specific proteins or cells. 6-Chloro-1H-indol-3-yl b-D-mannopyranoside is used as a diagnostic agent in the detection of bacterial and fungal infections. It is also used as an indicator of cell growth in culture media.