Indapamide-¹³C-d₃is intended for use as an internal standard for the quantification of indapamide by GC- or LC-MS. Indapamide is a carbonic anhydrase (CA) inhibitor (K_is = 0.23, 36, 10, and 13 nM for CAVII, CAIX, CAXII, and CAXIII, respectively).¹It is selective for these CAs over CAI-CAVI and CAXIV (K_is = 213->10,000 nM). Indapamide is a thiazide-like diuretic that reduces blood pressure in spontaneously hypertensive rats (SHRs).²It also increases urinary and renovascular levels of 11,12-EET and 14,15-EET, decreases urinary levels of 11,12-DiHET and 14,15-DiHET, and reduces renal cortical malondialdehyde levels in SHRs. Formulations containing indapamide have been used in the treatment of hypertension, as well as salt and fluid retention associated with congestive heart failure.

1.Temperini, C., Cecchi, A., Scozzafava, A., et al.Carbonic anhydrase inhibitors. Comparison of chlorthalidone and indapamide X-ray crystal structures in adducts with isozyme II: When three water molecules and the keto-enol tautomerism make the differenceJ. Med. Chem.52(2)322-328(2019) 2.Ma, F., Lin, F., Chen, C., et al.Indapamide lowers blood pressure by increasing production of epoxyeicosatrienoic acids in the kidneyMol. Pharmacol.84(2)286-295(2013)