英文别名5,6-Dihydro CP-690550; 5,6-Dihydro tofacitinib; Tofacitinib impurity 6; Tofacitinib Impurity; Tofacitinib Related Compound 21; Tofacitinib-21; Tofacitinib Impurity 39; (3R,4R)-3-((6,7-Dihydro-5H-pyrrolo[2,3-d]pyrimidin-4-yl)methylamino)-4-methyl-beta-oxo-1-piperidinepropanenitrile