Oxidation of 6-amino-5-benzylideneamino-1, 3-dimethyluracils (Ia-e) with nickel peroxide (Ni-PO) in dimethylsulfoxide (DMSO) afforded 8-substituted theophyllines (IIa-e) and dimethylsulfone. Ni-PO oxidation of the Schiff base acetate (V) of 5, 6-diamino-1, 3-dimethyluracil with D-glucose did not give a nucleoside analog ; in stead, 1, 3, 7, 9-tetramethyl-2, 4, 6, 8-(1H, 3H, 7H, 9H)pyrimido[5, 4-g]pteridinetetrone (VI) and penta-O-acetylgluconic acid were obtained. The reaction mechanisms of Ni-PO and the Schiff bases (Ia-e, V) are discussed.
在
二甲基亚砜(
DMSO)中,6-
氨基-5-苄叉
氨基-1,3-二甲基
脲(Ia-e)与
过氧化镍(Ni-PO)的氧化反应生成了8-取代的茶碱(IIa-e)和
二甲基亚砜。5,6-二
氨基-1,3-二甲基
脲与
D-葡萄糖形成的希夫碱
乙酸盐(V)在Ni-PO氧化下并未形成核苷类似物;取而代之,得到了1,3,7,9-四甲基-2,4,6,8-(1H,3H,7H,9H)
嘧啶[5,4-g]蝶啶四酮(VI)和五-O-乙酰基
葡糖酸。本文还讨论了Ni-PO与希夫碱(Ia-e, V)的反应机理。