(S)-6-butyl-2-(4-methoxybenzyl)-8-methyl-2,3,4,7,8,10-hexahydro-1H-pyrano[4,3-c][1,6]naphthyridine 、
3,4-二甲氧基苯甲醛 、
氰基硼氢化钠 在
(S)-6-butyl-2-(3,4-dimethoxybenzyl)-8-methyl-2,3,4,7,8,10-hexahydro-1H-pyrano[4,3-c][1,6]naphthyridine 、 hexanes 、
乙酸乙酯 作用下,
以gave 10d as a sticky light yellow oil (18.0 mg, 88% yield)的产率得到(S)-6-butyl-2-(3,4-dimethoxybenzyl)-8-methyl-2,3,4,7,8,10-hexahydro-1H-pyrano[4,3-c][1,6]naphthyridine