DIASTEREOSELECTIVE SYNTHESES OF N-PROTECTED DERIVATIVES OF A,5-ALPHA,6-BETA-6-AMINO-3-AZABICYCLO[3.1.0]HEXANE - A ROUTE TO TROVAFLOXACIN 6-BETA-DIASTEREOMER

N-Protected derivatives 12, 13 and 17 of 1 alpha,5 alpha,6 beta-6-amin o-3-azabicyclo[3.1.0]hexane 5 were synthesized via chloroenamines 6a o r 6b. The specific N-protection was realized either by using a chloroe namine 6b with different protecting groups or by selective removal of identical protecting groups at the bicyclic target molecule 7. Dibenzy lamino compound 13 allowed the preparation of naphthyridine derivative 25 which represents the 6 beta-diastereomer of trovafloxacin mesylate , a potent Gyrase inhibitor.