Tadalafil (Cialis) CAS: 171596-29-5 Assay: 99% min. USP32 Packing: 1kg net/foil bag, 5kg/drum. Delivery: Express courier. Character: White to Off-White Cyrstalline Solid. Usage: Used for the treatment of erectile dysfunction. A phosphodiesterase 5 inhibitor. pharmaceutical material. Categories: Active Pharmaceutical Ingredients; Cnbio; Erectile Dysfunction; Inhibitors; Intermediates & Fine Chemicals; Pharmaceuticals; API's.