Tadalafil is a PDE5 inhibitor marketed in pill form for treating erectile dysfunction (ED) under the name Cialis, and under the name Adcirca for the treatment of pulmonary arterial hypertension. In October 2011 the U.S. Food and Drug Administration (FDA) approved Cialis for treating the signs and symptoms of benign prostatic hyperplasia (BPH) as well as a combination of BPH and erectile dysfunction (ED) when the conditions coincide. It initially was developed by the biotechnology company ICOS, and then again developed and marketed world-wide by Lilly ICOS, LLC, the joint venture of ICOS Corporation and Eli Lilly and Company. Cialis tablets, in 2.5mg, 5mg, 10mg, and 20mg doses, are yellow, film-coated, and almond-shaped. The approved dose for pulmonary arterial hypertension is 40mg (two 20-mg tablets) once daily.

CAS：171596-29-5
中文别名：西力士;他地那非;
英文别名：Cialis;(6R,12aR)-6-(benzo[d][1,3]dioxol-5-yl)-2-methyl-2,3,12,12a tetrahydropyrazino [1\',2\':1,6] pyrido[3,4b] indole1,4(6H,7H)-dione;(6R,12aR)-6-(1,3-benzodioxol-5-yl)-2-methyl-2,3,6,7,12,12a-hexahydropyrazino[1\',2\':1,6]\r\npyrido[3,4-b]indole-1,4-dione;
分子式：C22H19N3O4
分子量：389.404
精确质量：389.138
Psa：74.87
Logp：2.0871

MDL号：MFCD07771966

外观与性状：灰白色水晶般的固体
密度：1.51 g/cm3
沸点：679.1ºC at 760 mmHg
熔点：298-300ºC
闪点：364.5ºC
折射率：1.705
蒸汽压：5.29E-13mmHg at 25°C

用途
磷酸二酯酶5抑制剂,用于治疗男性勃起功能障碍。