(R)-3-<(S)-1-ethoxycarbonyl-5-(4-piperidyl)pentyl>amino-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazapine-5-acetic acid   、                                                                                      
(S)-3-<(R)-1-ethoxycarbonyl-5-(4-piperidyl)pentyl>amino-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazapine-5-acetic acid                                                                                                                                                                                              以
                                                                                         
乙醇                                                                                  为溶剂,
                                                                                                                                                                                        以62%的产率得到(R)-3-<(S)-carboxy-5-(4-piperidyl)pentyl>amino-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-acetic acid