Romidepsin strongly inhibits HDAC1 and HDAC2 with IC50 of 1.6 nM and 3.9 nM, respectively, but is relatively weak in inhibiting HDAC4 and HDAC6 with IC50 25 nM and 790 nM, respectively.

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

Rocilinostat (ACY-1215) is a selective HDAC6 inhibitor with IC50 of 5 nM; >10-fold more selective for HDAC6 than HDAC1/2/3 (class I HDACs) with slight activity against HDAC8, minimal activity against HDAC4/5/7/9/11, Sirtuin1, and Sirtuin2.

ROC-325 is a Novel Small Molecule Inhibitor of Autophagy with Promising Anti-Leukemic Activity.

Ro-3306 is a potent and selective inhibitor of CDK1 with Ki value of 35 nM for CDK1/cyclin B1, 10-fold selectivity relative to CDK2/cyclin E and >50-fold relative to CDK4/cyclin D.

RO0921 is a novel, potent SYK inhibitor.

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

Ro 31-8220 mesylate (Bisindolylmaleimide IX) is a pan-PKC inhibitor with IC50 of 5 nM, 24 nM, 14 nM, 27 nM, and 24 nM for PKC-α, PKC-βI, PKC-βII, PKC-γ, and PKC-ε, respectively.

RN-486 is a Bruton's tyrosine kinase (Btk) inhibitor.

RN-1734 is a transient receptor potential vanilloid 4 (TRPV4) antagonist, blocking calcium influx induced by the TRPV4 agonist 4α-phorbol 12,13-didecanoate with IC50 values of 2.3, 5.9, and 3.2 µM for human, mouse, and rat TRPV4, respectively.

RN-1 is an inhibitor of lysine specific demethylase 1 (LSD1); exhibits selectivity for LSD1 over monoamine oxidase (MAO)-A and MAO-B (IC50 values are 70 nM, 0.51 and 2.79 μM respectively.

RKI-1447 is a potent small molecule inhibitor of ROCK1 and ROCK2.

RKI-1313 is the negative control for RKI-1447 which is a potent inhibitor of the Rho-associated ROCK kinases with anti-invasive and antitumor activities in breast cancer

RK-33 is a novel DDX3 inhibitor for lung cancer therapy.

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.

Risperidone(R 64 766) is a serotonin 5-HT2 receptor blocker(Ki= 0.16 nM) and a potent dopamine D2 receptor antagonist(Ki= 1.4 nM).

Rimonabant(SR141716) is a selective central cannabinoid (CB1) receptor inverse agonist with Ki of 1.8 nM.

Rimonabant Hcl(SR141716A) is a selective central cannabinoid (CB1) receptor inverse agonist with Ki of 1.8 nM.

Riluzole is a glutamate antagonist used as an anticonvulsant and to prolong the survival of patients with amyotrophic lateral sclerosis.

Rilpivirine(R 278474, TMC 278) is a type of anti-HIV medicine called a non-nucleoside reverse transcriptase inhibitor (NNRTI).

Rigosertib (ON-01910) is a non-ATP-competitive inhibitor of PLK1 with IC50 of 9 nM; shows 30-fold greater selectivity against PLK2 and no activity to PLK3.

RI-2 is an optimized RAD51 inhibitor with an IC50 of 44.17 μM in the standard DNA binding assay; specifically inhibits HR(Homologous recombination) repair in human cells.

RGX-104 is an orally bioavailable agonist of the nuclear receptor liver X receptor beta (LXRbeta; NR1H2; LXR-b), with potential immunomodulating and antineoplastic activities.

RGFP966 is specific inhibitor of HDAC3, with an IC50 of 0.08 μM and no effective inhibition of any other HDAC at concentrations up to 15 μM.

RGB-286638 is a novel CDK inhibitor with IC50s of 1 nM/2 nM/3 nM/4 nM/5 nM for cyclin T1-CDK9/cyclin B1-CDK1/cyclin E-CDK2/cyclin D1-CDK4/cyclin E-CDK3/p35-CDK5 respectively; less potent against cyclin H-CDK7 and cyclin D3-CDK6.

RG7090(CTEP Derivative,Basimglurant, RO4917523) is a negative modulator of metabotropic glutamate receptor subtype 5 (mGluR5; GRM5).

RG108 is an inhibitor of DNA methyltransferase with IC50 of 115 nM, does not cause trapping of covalent enzymes.

Reversine, a small synthetic purine analogue (2,6-disubstituted purine), is a potent inhibitior of Aurora A/B/C with IC50s of 150-500 nM.

Retigabine is a novel anti-convulsant, enhances activation of KCNQ2/Q3 potassium channels.

RepSox(E-616452; SJN 2511) is a potent and selective inhibitor of the TGFβR-1/ALK5 with IC50 of 23 nM and 4 nM for ATP binding to ALK5 and ALK5 autophosphorylation, respectively.