Racecadotril (acetorphan), a potent enkephalinase inhibitor (IC50= 4.5 uM), protects endogenous enkephalins from degradation.

Ramipril is an angiotensin-converting enzyme (ACE) inhibitor with IC50 of 5 nM.

Raphin1 is an orally available selective phosphatase inhibitor improves proteostasis and diminishes deficits in a mouse model of Huntington’s disease.

Razuprotafib is a potent protein tyrosine phosphatase β (HPTPβ) inhibitor..

Razuprotafib sodium is a potent protein tyrosine phosphatase β(HPTPβ) inhibitor..

Rivaroxaban (Xarelto; BAY 59-7939) is a novel, oral, direct Factor Xa (FXa) inhibitor in late-stage development for the prevention and treatment of thromboembolic disorders.

Rivastigmine hydrogen tartrate is a parasympathomimetic or cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer’s type and Parkinson's disease.

RMC-4550 (RMC4550) is a potent, selective, allosteric inhibitor of SHP2 with IC50 of 0.58 nM (full-length SHP2 enzyme), suppresses pERK signaling in Calu-1 cells with IC50 of 7 nM.

Ro 28-1675 (Ro 0281675) is a potent allosteric GK activator with a SC1.5 value of 0.24± 0.0019 uM.

Ro 41-1049 hydrochloride is a selective, reversible inhibitor of MAO-A.

Ro 61-8048 is a potent and competitive kynurenine 3-hydroxylase inhibitor (Ki = 4.8 nM, IC50 = 37 nM).

Roflumilast (Daxas) is a selective inhibitor of PDE4 with IC50 of 0.2-4.3 nM.

Roxyl-WL is a highly potent and selective inhibitor of IDO1 with IC50 of 1 nM.

RPL-554 (LS-193855, RPL554) is a potent, orally available, dual PDE3/PDE4 inhibitor with IC50 of 0.4 nM and 1479 nM, respectively.

Safinamide (EMD 1195686; FCE 26743) selectively and reversibly inhibits MAO-B with IC50 of 98 nM, exhibits 5918-fold selectivity against MAO-A.

Saxagliptin is a selective and reversible DPP4 inhibitor with IC50 of 26 nM and Ki of 1.3 nM.

SB-3CT is an effective and selective gelatinase inhibitor with Ki of 13.9 nM and 600 nM for MMP-2 and MMP-9, respectively.

SEP-0372814 is a potent PDE10 inhibitor.

SHP099 is a selective, orally bioavailable, and efficacious SHP2 inhibitor with IC50 =0.07 μM and p-ERK modulation in cells IC50 = 0.250 μM.

SHP099 is a selective, orally bioavailable, and efficacious SHP2 inhibitor with IC50 =0.07 μM and p-ERK modulation in cells IC50 = 0.250 μM.

Sildenafil citrate, one of the selective phosphodiesterase-5 (PDE5) inhibitors(IC50= 5.22 nM), is considered the best treatment for erectile dysfunction.

Simvastatin (MK 733) is a competitive inhibitor of HMG-CoA reductase with a Ki of 0.2 nM.