Photoinduced electron transfer and chemical α-deoxygenation of d-galactono-1,4-lactone. Synthesis of 2-deoxy-d-lyxo-hexofuranosides
作者:Alejandro Chiocconi、Carla Marino、Eugenio Otal、Rosa M de Lederkremer
DOI:10.1016/s0008-6215(02)00118-0
日期:2002.11
Two simple procedures for the synthesis of 2-deoxy-D-lyxo-hexono-1,4-lactone are described. Reductive cleavage of a 2-O-tosyl derivative of D-galactono-1,4-lactone in the presence of sodium iodide afforded the 2-deoxy derivative. On the other hand, alpha-deoxygenation of D-galactono-1,4-lactone was easily achieved by photochemical electron transfer deoxygenation of HO-2 as the 3-(trifluoromethyl)benzoate
描述了两个简单的合成2-脱氧-D-lyxo-六邻--1,4-内酯的程序。在碘化钠的存在下,D-半乳糖-1,4-内酯的2-O-甲苯磺酰基衍生物的还原裂解得到2-脱氧衍生物。另一方面,通过将HO-2作为3-(三氟甲基)苯甲酸酯进行光化学电子转移脱氧,可以容易地实现D-半乳糖-1,4-内酯的α-脱氧。合成了甲基2-脱氧-β-D-lyxo-六呋喃糖苷(“甲基2-脱氧-β-D-半乳糖呋喃糖苷”),并测试了其作为来自腐霉青霉的exoβ-D-半乳糖苷酶的底物。在反应之后进行HPAEC,显示2-脱氧-β-D-D-半乳糖呋喃糖苷甲基未通过与酶温育而水解。2-脱氧内酯 2-脱氧-β-D-半乳糖呋喃糖苷也不能充当与4-硝基苯基β-D-半乳糖醛糖苷反应的抑制剂。目前和我们以前的结果表明,半乳糖呋喃糖苷的C-2,C-3和C-6处的羟基对于与外切β-D-半乳糖醛酸苷酶的相互作用至关重要。