2-Aza-bicyclo[2.2.1]heptane-2,3-dicarboxylic acid 3-(2-{9-[2-(1-tert-butoxycarbonyl-pyrrolidine-2-carbonyloxy)-acetyl]-5,7-dihydro-dibenzo[c,e]oxepin-3-yl}-2-oxo-ethyl) ester 2-tert-butyl ester|Huagongshe