[(1S)-1-[(4R)-4-benzyl-5-oxotetrahydrofuran-(2R)-2-yl]-3-(2,4,6-trimethoxybenzylcarbamoyl)propyl]carbamic acid tert-butyl ester

(2R,4R,5S)-2-benzyl-5-tert-butoxycarbonylamino-4-(tert-butyldimethylsilanyloxy)-7-(2,4,6-trimethoxybenzylcarbamoyl)heptanoic acid