(3S,4R)-Tofacitinib (Tofacitinib Impurity B) is a less active isomer/enantiomer of Tofacitinib (CP-690550; tasocitinib; Xeljanz), which is an inhibitor of JAK3 (Janus-Associated kinase, IC50 = 1 nM) and an FDA approved drug for the treatment of rheumatoid arthritis (RA), psoriatic arthritis, and ulcerative colitis.

XL019 is a novel, potent and selective and orally bioavailable inhibitor of Janus kinase-JAK2 with potential antitumor activity.

AT9283 is a novel, potent and selective inhibitor of multikinase including Aurora A/B, JAK2/3, Abl (T315I) and Flt3 etc.

AZ 960 (AZ-960) is a novel, potent, selective and ATP competitive JAK2 (janus kinase) inhibitor with potential antitumor activity.

Itacitinib (also known as INCB39110) is a potent, selective and orally bioavailable inhibitor of JAK1 (Janus-associated kinase 1) with >20-fold selectivity for JAK1 over JAK2 and >100-fold over JAK3 and TYK2 (IC50 for JAK1, 2, 3, and TYK2 are 2, 63, >2000, and 795 nM, respectively).

CHZ868 is a novel, potent and selective type II JAK2 inhibitor with an IC50 of 0.17 μM in EPOR JAK2 WT Ba/F3 cell.

Tofacitinib (also known as tasocitinib or CP-690550, sold under the brand Xeljanz), is a novel and potent inhibitor of JAK3 (Janus-Associated kinase) with potential anti-inflammatory activity.

Solcitinib (formerly GSK2586184; GSK-2586184A; GLPG-0778; GLPG0778) is a potent, selective, and orally bioavailable Janus kinase (JAK)1 inhibitor being evaluated as a treatment for moderate-to-severe plaque-type psoriasis.

(3R,4S)-Tofacitinib (Tofacitinib Impurity A) is a less active diastereomer/enantiomer of Tofacitinib (CP 690550; tasocitinib; Xeljanz), which is a JAK3 (Janus-Associated kinase) inhibitor and an FDA approved drug for the treatment of rheumatoid arthritis (RA), psoriatic arthritis, and ulcerative colitis.

SAR-20347 is a novel and potent small molecule inhibitor with specificity for JAK1 and tyrosine kinase 2 (TYK2) over other JAK family members.