(+)-(4S)-4-benzyl-2-methyl-1-methylene-2,4-dihydro-1H-pyrazino[2,1-b]quinazoline-3,6-dione 在
三氟乙酸 作用下,
反应 4.0h,
以40%的产率得到(+)-(1S,4S)-4-benzyl-2-methyl-1-{2-[(4'S)-4'-benzyl-2'-methyl-3',6'-dioxo-2',3',4',6'-tetrahydro-1'H-pyrazino[2,1-b]quinazolinylidene]ethyl}-2,4-dihydro-1H-pyrazino[2,1-b]quinazoline-3,6-dione