AMI-1 free acid
                                    
                                        
                                            AMI-1 free acid is a potent, cell-permeable and reversible inhibitor of protein arginine N-methyltransferases (PRMTs), with IC50s of 8.8 μM and 3.0 μM for human PRMT1 and yeast-Hmt1p, respectively. AMI-1 free acid exerts PRMTs inhibitory effects by blocking peptide-substrate binding.