4-THIA-1-AZABICYCLO[3.2.0]HEPTANE-2-CARBOXYLIC ACID, 6-BROMO-6-(HYDROXYMETHYL)-3,3-DIMETHYL-7-OXO-, (1R)-1-(BENZOYLOXY)ETHYL ESTER, 4,4-DIOXIDE, (2S,5R,6S)-