Background:

ML221 is a potent apelin (APJ) functional antagonist, inhibiting apelin-13-mediated activation of APJ, with IC50s of 0.70 μM in the cAMP assay, and 1.75 μM in the β-arrestin assay, and EC80 of 10 nM in both assays.

ML221 is a potent apelin/APJ functional antagonist, inhibiting apelin-13-mediated activation of APJ, with IC50s of 0.70 μM in the cAMP assay, and 1.75 μM in the β-arrestin assay, and EC80 of 10 nM in both assays. ML221 is >37-fold selective over the closely related angiotensin II type 1 (AT1) receptor (IC50, >79 μM) in cells. ML221 displays limited cross reactivity against a range of GPCRs except the κ-opioid and benzodiazepinone receptors (<50>

参考文献:
[1]. Maloney PR, et al. Discovery of 4-oxo-6-((pyrimidin-2-ylthio)methyl)-4H-pyran-3-yl 4-nitrobenzoate (ML221) as a functional antagonist of the apelin (APJ) receptor. Bioorg Med Chem Lett. 2012 Nov 1;22(21):6656-60.