ethyl 2-(2-chloroethyl)-3,4-dihydro-5-methyl-4-oxothieno[2,3-d]pyrimidin 6-carboxylate   、                                                                                      
(5-Methyl-1H-benzoimidazol-2-yl)-methanethiol                                                                                                                                                              在
                                                                                                                                                                                 sodium hydroxide                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
乙醇                                                                                  为溶剂,
                                                                                                                                                    反应 3.0h,
                                                                                                                以49%的产率得到ethyl 2-{2-[(5(6)-methyl-1H-benzimidazol-2-ylmethyl)thio]ethyl}-5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxylate