CL-315555 is the C isomer of [Verteporfin].

CL-315585 is the D isomer of [Verteporfin].

Verteporfin, marketed as Visudyne, is a benzoporphyrin derivative comprising a 50:50 mixture of two isomers: [CL-315555] and [CL-315585]. It is used as a photosensitizer in photodynamic therapy to eliminate abnormal blood vessels in wet form macular degenerat…