7-[[(7R)-7-ethyl-8-isopropyl-5-methyl-6-oxo-7H-pteridin-2-yl]amino]-2,3-dihydrobenzofuran-4-carboxylic acid   、                                                                                      
(cis-endo)-2-methyl-3,3a,4,5,6,6a-hexahydro-1H-cyclopenta[c]pyrrol-5-ylamine                                                                                                                                                              在
                                                                                                                                                                                 O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate   、                                                                                                  
N,N-二异丙基乙胺                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                    反应 2.0h,
                                                                                                                以52%的产率得到(cis-endo)-N-[2-methyl-3,3a,4,5,6,6a-hexahydro-1H-cyclopenta[c]pyrrol-5-yl]-7-[[(7R)-7-ethyl-8-isopropyl-5-methyl-6-oxo-7H-pteridin-2-yl]amino]-2,3-dihydrobenzofuran-4-carboxamide