for the following products
(2R,3R)-3-(2-(tert-Butyldimethylsilyloxy)ethyl)-4-oxoazetidin-2-yl acetate | (3R,4R)-4-Acetoxy-3-((R)-(tert-butyldimethylsilyloxy)ethyl)-2-azetidinone | (3R,4R)-4-Acetoxy-3-[(3R)-tert-butyldimethylsilyloxy)ethyl]-2-azetidinone | (3R,4R)-4-Acetoxy-3-[(R)-1-(tert-butyldimethylsilyloxy)ethyl]-2-azetidinone | [3R(1'R,4R)]-(+)-4-Acetoxy-3-[1-(tert-butyldimethylsilyloxy)ethyl]-2-azetidinone and 4-Acetoxyazetidine-2-one( 4-AA, ABA, AOSA)
