(3R,3'S)-3-[(tritylthio)methyl]spiro[dihydropyrazine-2,5-dione-6,3'-(2',3'-dihydrothieno[2,3-b]naphtho-4',9'-dione)]                                                                                                                                                              在
                                                                                                                                                                                 
三氟乙酸                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                                                        以82%的产率得到(3R,3'S)-3-(mercaptomethyl)spiro[(dihydropyrazine-2,5-dione)-6,3'-(2',3'-dihydrothieno[2,3-b]naphtho-4',9'-dione)]