Compounds of the formula ##STR1## where R is a base labile substituted-phenyloxy protecting group, are useful as phosphorylating reagents in the synthesis of oligonucleotides by a phosphotriester method. Such compounds are made by the reaction of .beta.-cyanoethanol and a corresponding R-phosphorodichloridate. A method of phosphorylating involves reacting such compounds, in the presence of base, with a nucleoside or a polynucleotide having a free 3' hydroxyl group, having the 5'--0 position protected by an organic group labile in acidic medium and having any phosphotriester linking groups protected by an organic group labile in strong basic medium.
式为##STR1##的化合物,其中R是一种易于基础脱保护的取代苯氧基团,可用作
磷酰化试剂,在
磷酸三酯法合成寡核苷酸时起作用。这些化合物是通过β-
氰乙醇与相应的R-
磷酸二
氯代酯反应制备的。一种
磷酰化方法涉及在碱存在的情况下,将这些化合物与具有游离3'羟基的核苷或多核苷酸反应,其中5'--0位置由在酸性介质中易于脱保护的有机基团保护,任何
磷酸三酯连接基团由在强碱性介质中易于脱保护的有机基团保护。