Eto M, Kawasaki S
Nucleic Acids Symp Ser. 1986(17):65-8.
Adenosine borate complex was phosphorylated and o-hydroxybenzylated by 2-methylthio-4H-1,3,2-benzodioxaphosphorin 2-oxide (MTBO) in the presence of 4-morpholine-N,N'-dicyclohexylcarboxamidine (MDC) at first to give 1-(o-hydroxybenzyl)adenosine derivative followed by the rearrangement of the benzyl group to the N-6 amino group to give N6-(o-hydroxybenzyl)adenosine 5'-S-methyl phosphorothiolate. More than 20 analogs of MDC were examined for their catalytic activity in phosphorylation and o-hydroxybenzylation of ribonucleoside by MTBO. Dicyclohexylformamidine (DCF) and n-alkylamino analogs of MDC had no effect on the o-hydroxybenzylation of ribonucleoside by MTBO, but had great effect on the phosphorylation. Dialkylamino and cyclic imino analogs of MDC had high catalytic activities to the both reaction. The dicyclohexylcarboxamidine structure of MDC gave the catalytic ability for phosphorylation by MTBO, while the morpholine moiety had great effect on the selectivity of o-hydroxybenzylation by MTBO.
首先，在4-吗啉-N,N'-二环己基甲脒（MDC）存在下，硼酸腺苷络合物被2-甲硫基-4H-1,3,2-苯并二氧磷杂环己二烯2-氧化物（MTBO）磷酸化并邻羟基苄基化，得到1-(邻羟基苄基)腺苷衍生物，随后苄基重排至N-6氨基，得到N6-(邻羟基苄基)腺苷5'-S-甲基硫代磷酸酯。对20多种MDC类似物进行了研究，考察它们在MTBO对核糖核苷的磷酸化和邻羟基苄基化反应中的催化活性。二环己基甲脒（DCF）和MDC的正烷基氨基类似物对MTBO对核糖核苷的邻羟基苄基化反应无影响，但对磷酸化反应有很大影响。MDC的二烷基氨基和环状亚氨基类似物对这两个反应均具有高催化活性。MDC的二环己基甲脒结构赋予了其被MTBO磷酸化的催化能力，而吗啉部分对MTBO邻羟基苄基化反应的选择性有很大影响。
