Apr. 8, 2004  24  US 2004/0067216 Al  2, 6-lutidine  HO  TfO  2  1. TBSCl, imidazole  I  5  LiOH  DME  SCHEME 1  Boc’-Nl  /:(  N  0  H  3  4  Boc,Nl  1 .,.-TBS(R 4  :(~NHR’  0  NH  I  R6  10  Boe, l  R 4  N  ~H  TBAF  lliC  ):N  O  NUR’  0  NH  I  R6  7  8 