N-(2-(3-benzyloxy-1,4-dihydro-2-methyl-4-oxo-1-pyridinyl)ethyl)-3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-benzopyran-2-carboxamide 以77%的产率得到N-(2-(1,4-Dihydro-3-hydroxy-2-methyl-4-oxo-1-pyridinyl)ethyl)-3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-benzopyran-2-carboxamide