On treatment of 2-p-chlorophenylthiazinothiamine (Ib) with hydrogen peroxide, 2-hydroxy-2-p-chlorophenylthiazinothiamine (IIb) was obtained. Similar reaction products of phenyl-and methylthiazinothiamine (Ia and Ie) were reinvestigated and found to be IIb analogues (IIa and IIe, respectively). Reactions of IIa, IIb or IIe with acetic anhydride afforded the corresponding N-(2-methyl-4-aminopyrimidin-5-yl) methyl-N-(2-acetylthio-4-amino-1-methyl-1-butenyl) aryl (or methyl) oxalamide (IIIa, IIIb or IIIe, respectively). Treatment of 2-o-tolylthiazinothiamine (Ic) with hydrogen peroxide gave N-[1-(2-oxido-1, 2-oxathiolan-3-ylidene) ethyl]-N-[(2-methyl-4-aminopyrimidin-5-yl) methyl]-o-tolyloxalamide (VIIIc) as a major product and similar treatment of o-methoxyphenylthiazinothiamine (Id) with hydrogen peroxide gave 1-(2-methyl-4-aminopyrimidin-5-yl) methyl-2-methyl-3-(2-hydroxyethyl)-4-hydroxy-4-(2-methoxyphenyl)-⊿2-pyrrolin-5-one (XV). Oxidations of Ia, Ic and Id with m-chloroperbenzoic acid also gave VIIIc and the corresponding VIIIc analogues (VIIIa and VIIId, respectively). The mechanisms of these reactions are discussed as shown in Chart 2.
用
过氧化氢处理 2-对
氯苯基
噻嗪硫胺(Ib)后,得到 2-羟基-2-对
氯苯基
噻嗪硫胺(IIb)。对苯基和甲基
噻嗪硫胺(Ia 和 Ie)的类似反应产物进行了重新研究,发现它们分别是 IIb 类似物(IIa 和 IIe)。将 IIa、IIb 或 IIe 与
乙酸酐反应,可得到相应的 N-(2-甲基-4-
氨基嘧啶-5-基)甲基-N-(2-乙酰
硫基-4-
氨基-1-甲基-1-
丁烯基)芳基(或甲基)草酰胺(分别为 IIIa、IIIb 或 IIIe)。用
过氧化氢处理 2-邻
甲苯基
噻嗪硫胺(Ic)可得到 N-[1-(2-氧代-1、2-(2-甲基-4-
氨基嘧啶-5-基)甲基]-N-[(2-甲基-4-
氨基嘧啶-5-基)甲基]-邻
甲苯基柳酰胺(VIIIc)作为主要产物,用
过氧化氢处理邻
甲氧基苯基
噻嗪硫胺(Id)得到 1-(2-甲基-4-
氨基嘧啶-5-基)甲基-2-甲基-3-(2-羟乙基)-
4-羟基-4-(2-
甲氧基苯基)-⊿2-
吡咯啉-5-酮 (XV)。用间
氯过
苯甲酸氧化 Ia、Ic 和 Id 还可得到 VIIIc 和相应的 VIIIc 类似物(分别为 VIIIa 和 VIIId)。这些反应的机理如图 2 所示。