Improved synthesis of 6-amino-6-deoxy-D-galactono-1,6-lactam and D-mannono-1,6-lactam from corresponding unprotected D-hexono-1,4-lactones

Regioselective bromination of unprotected D-galactono-1,4-lactone and D-mannono-1,4-lactone with PPh3/CBr4 led to 6-bromo-6-deoxy derivatives. These intermediates were treated with LiN3 and hydrogenated to give 6-amino-6-deoxy-D-galactono-1,6-lactam (8) and 6-amino-6-deoxy-D-mannono-1,6-lactam (13) in 74 and 67% overall yield, respectively. (C) 2004 Elsevier Ltd. All rights reserved.