Telmisartan-d7 (BIBR 277-d7) is a deuterium labeled Telmisartan (HY-13955). Telmisartan is a potent, long lasting antagonist of angiotensin II type 1 receptor (AT1), selectively inhibiting the binding of 125I-AngII to AT1 receptors with IC50 of 9.2 nM.