CARBAMIC ACID, N-[(1R,3R)-3-AMINOCYCLOPENTYL]-, 1,1-DIMETHYLETHYL ESTER, REL-

tert-Butyl(trans-3-Aminocyclopentyl)carbamate is used in the synthetic preparation of imidazo-pyrrolopyridines as JAK1 inhibitors, which are proposed to treat inflammatory diseases such as rheumatoid arthritis.