(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.