Synthesis and Photocyclization of .alpha.-Methylene-.gamma.-butyrolactone-Thymine Heterodimers
作者:Elena Gimenez-Arnau、Stephane Mabic、Jean-Pierre Lepoittevin
DOI:10.1021/tx00043a002
日期:1995.1
ne--thymine heterodimers 6 and 7 with 5 and 10 carbon alkyl chains, respectively, were prepared to study the photoreactivity of lactone rings toward thymine and the influence of spacer length on photoadduct geometry. Deoxygenated solutions (10(-3) M) of heterodimers 6 and 7 were irradiated at 365 nm in acetone. Irradiation of compound 6 (5 carbons alkyl chain) gave a single photoadduct 8 (70% yield)
分别制备了两个具有5和10个碳烷基链的α-亚甲基-γ-丁内酯-胸腺嘧啶异二聚体6和7,以研究内酯环对胸腺嘧啶的光反应性以及间隔基长度对光加合物几何形状的影响。异二聚体6和7的脱氧溶液(10(-3)M)在丙酮中于365 nm照射。辐照化合物6(5个碳原子的烷基链)得到一个光加合物8(70%收率),而辐照化合物7(10个碳原子的烷基链)则以3/2的比例得到两个光加合物9a和9b(95%收率)。化合物8被鉴定为涉及胸腺嘧啶部分的5“,6”双键和内酯的3,6外亚甲基基团的顺式-内-内分子内[2 + 2]光加合物。化合物9a被鉴定为顺式-syn-exo分子内[2 + 2]光加合物,涉及5“,6”