phenyl N-benzyl-2-amino-6-O-benzyl-2,3-N,O-carbonyl-2-deoxy-1-thio-β-D-galactopyranoside   、                                                                                      
N-benzyl-2-amino-6-O-benzyl-2,3-N,O-carbonyl-4-O-chloroacetyl-2-deoxy-α-D-glucopyranosyl bromide                                                                                                                                                              在
                                                                                                                                                                                 
2,6-二叔丁基-4-甲基吡啶   、                                                                                                  4 Angstroem MS   、                                                                                                  
silver trifluoromethanesulfonate                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
1,4-二氧六环   、                                                                                         
甲苯                                                                                  为溶剂,
                                                                                                                                                                                        以80%的产率得到Chloro-acetic acid (3aR,4R,6R,7S,7aR)-3-benzyl-4-((3aR,4S,6R,7R,7aR)-3-benzyl-6-benzyloxymethyl-2-oxo-4-phenylsulfanyl-hexahydro-pyrano[3,4-d]oxazol-7-yloxy)-6-benzyloxymethyl-2-oxo-hexahydro-pyrano[3,4-d]oxazol-7-yl ester