LABORATORY SYNTHESIS OF NUCLEOSIDES AND NUCLEOTIDES

Silyl-Hilbert-Johnson nucleosidation.Benzoyl protected sugar (d-ribose) reacts in the presence of tin(IV)chloride with an N-benzoyl protected base (cytidine), protected further by insitu sylation using BSA (step 1) and they are removed with acid (step 2). Benzoyl can be remve by using base

Another techniques involves formation of the heterocyclic base on a protected ribosylamine derivative

Synthesis of nucleoside with a substituent in the heterocyclic ring that can be replaced with other group

Numerous phosphorilating agents have been used to convert nucleosides to nucleotides.One of the most usefull is dibenzyl phosphochloridate: Bn=benzylSpecific phosphorilation of the 5’-OH can be achived if the 2’- and 3’-OH groups of the nucleoside are protected by an acetonide group.Mild acid catalysed hydrolysis remove acetonide group, and hydrogenolysis cleaves the benzyl phosphate bonds.

QUESTION:1. What is the stucture of I and II?2. Propose a mechanism that explain the formation of II?

QUESTION: Explain the medical application of these following purine derivatives compounds

mutation