Purines. LXXI. Preparation and Alkylation of 7-Alkyladenine 1-Oxides: A General Synthesis of 1-Alkoxy-7-alkyladenines.
作者:Taisuke ITAYA、Nobuaki ITO、Tozo FUJII
DOI:10.1248/cpb.44.594
日期:——
7-Methyladenine (6a) and 7-ethyladenine (6b) afforded the N(1)-oxides 7a, b in 78% yield each on treatment with m-chloroperoxybenzoic acid at room temperature; this is analogous to the previously reported N-oxidation of 7-benzyladenine (6c) to give the N(1)-oxide 7c. When treated with an excess of methyl iodide, ethyl iodide, or benzyl bromide in N, N-dimethylacetamide at room temperature, each of the 1-oxides 7a-c underwent alkylation almost exculsively at the oxygen atom of the N-oxide group. The products, isolated in good yields, were the salts 8d-l·HX of the nine 1-alkoxy-7-alkyladenines, in which either the O-alkyl or the N(7)-alkyl group is any one of methyl, ethyl, and benzyl. The UV and 1H-NMR spectral data for 8·HX and some of their free bases 8 are presented.
室温下,用间氯过氧苯甲酸处理 7-甲基腺嘌呤(6a)和 7-乙基腺嘌呤(6b),可得到 N(1)-氧化物 7a、b,收率分别为 78%;这与之前报道的 7-苄基腺嘌呤(6c)发生 N-氧化反应得到 N(1)-氧化物 7c 相似。室温下,在 N,N-二甲基乙酰胺中用过量的碘化甲酯、碘化乙酯或溴化苄处理时,每种 1-氧化物 7a-c 几乎都会在 N-氧化基团的氧原子上发生烷基化反应。以良好的产率分离出的产物是九种 1-烷氧基-7-烷基腺嘌呤的盐 8d-l-HX,其中 O-烷基或 N(7)-烷基是甲基、乙基和苄基中的任意一种。文中给出了 8-HX 及其一些游离碱 8 的紫外光谱和 1H-NMR 光谱数据。