Optimized Method for the Synthesis and Purification of Adenosine - Folic Acid Conjugates for use as Transcription Initiators in the Preparation of Modified RNA

Abstract We present an optimized synthetic strategy for the attachment of molecules to 5′-adenosine monophosphate (AMP), which can then be used to label the 5′-end of RNA by T7 RNA polymerase mediated in vitro transcription. Through the use of a boronate affinity gel, we have developed an efficient route to the preparation of folate conjugated AMP with high yields and purity. Affi-Gel boronate is an affinity resin that selectively binds nucleoside and nucleoside derivatives at pH > 7.5 and releases them at pH