Ambrisentan (CAS 177036-94-1) – Selective ETA Receptor Antagonist PAH API

Ambrisentan (CAS 177036-94-1) is a high-purity pharmaceutical API, a selective ETA (endothelin type A) receptor antagonist derived from diphenylpropionic acid. Its chiral molecular structure shows strong affinity for ETA receptors (Ki = 1nM) while minimizing binding to ETB receptors, which avoids interfering with beneficial ETB – mediated vasodilation and tissue protection. This specificity enables targeted vasodilation of pulmonary arteries, effectively reducing pulmonary vascular resistance without affecting systemic blood pressure, a key advantage over non – selective endothelin antagonists.

As a white to off – white crystalline powder, it has good solubility in organic solvents, suitable for formulating oral tablets and suspensions with once – daily dosing convenience. It strictly complies with GMP standards and meets the needs of pulmonary hypertension drug manufacturers, cardiovascular drug developers and clinical supply chains. It is mainly indicated for WHO Group I pulmonary arterial hypertension (PAH) to improve exercise capacity, delay clinical deterioration and reduce hospitalization risksNational Center for Biotechnology Information. Compared with similar drugs, it has fewer drug interactions and lower liver injury risks, which is a reliable raw material for long – term PAH treatment.