著者
/ 藤井 澄三 斎藤 徹 TOHRU SAITO
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.34, no.5, pp.2037-2043, 1986-05-25 (Released:2008-03-31)
参考文献数
28
被引用文献数
9 14

A detailed account is given of the final step of the general 7-alkalation procedure for adenine (1), which consists of the preferential benzylation at the 3-position of 1, regioselective alkylation of the resulting 3-benzyladenine (2) to give 7-alkyl-3-benzyladenine salts (3a-c), and debenzylation of 3a-c leading to 7-alkyladenines (4a-c). Debenzylation of 3a-c (X=Cl or ClO4) has been achieved by hydrogenolysis using hydrogen and Pd-C catalyst at atmospheric pressure, producing 7-alkyladenines (4a-c) in 38-74% yields. The use of the allyl or γ, γ-dimethylallyl group at the 3-position instead of the benzyl group for the synthesis of 7-methyladenine (4a) by this procedure has no practical value. Alternatively, the salts 3a-c (X=Br, ClO4, or I) have been debenzylated efficiently by treatment with conc. H2SO4 in the presence of toluene at room temperature for 3-6h or at 60°C for 0.5-2h, giving 4a-c in 73-93% yields.