(1S,2S,3aR,8bS)-1-azido-7-bromo-2-hydroxy-2,3,3a,8b-tetrahydro-1H-cyclopenta[b]benzofuran-5-carboxylic acid methyl ester 以76%的产率得到(1S,2S,3aR,8bS)-1-benzenesulfonamido-2-hydroxy-2,3,3a,8b-tetrahydro-1H-cyclopenta[b]benzofuran-5-carboxylic acid methyl ester