6-(1,2-Dihydroxy-propyl)-2-(dimethylamino-methyleneamino)-4-oxo-4,6,7,8-tetrahydro-1H-pteridine-5-carboxylic acid tert-butyl ester   、                                                                                      
BOC-L-脯氨酸                                                                                                                                                                                                                                                                                                          以to give the sub-title compound as a pale yellow solid (3.0 g, 60%)的产率得到1,2,4-三嗪,3-[2-(4,5-二氢-1H-咪唑-2-基)肼基]-5,6-二甲基-