(3R,4R)-N,4-Dimethyl-1-(phenylmethyl)-3-piperidinamine Hydrochloride is a related compound of Tofacitinib (T528000). (3R,4R)-N,4-Dimethyl-1-(phenylmethyl)-3-piperidinamine Hydrochloride can be used to prepare janus kinase 1 selective inhibitor.