Chapter 29. Nucleosides and Nucleotides

Abstract

The preparation of nucleosides by the fusion method continues to be employed extensively. Iodine has been found to be an effective catalyst for the synthesis of certain nucleosides by the fusion method. Nebularine has been synthesized in high yield by the fusion technique using bis-(p-nitrophenyl) hydrogen phosphate as the catalyst. Nucleosides are prepared by the fusion method from homoribose with 6-chloro-, and 2, 6-dichloropurines. The corresponding 6-mercapto and 2-chloro-6-aminopurine nucleosides are nontoxic in tissue culture. A variety of aldofuranosyl nucleosides have been pre-pared by the chloromercuri procedure. The utilization of the 2,4-dinitrophenyl group as a blocking group in the preparation of 2 ′ -amino-2 ′ - deoxy-nucleosides has been described in the synthesis of 2 ′ -amino-2 ′ -deoxy-adenosine. The synthesis and biological function of nucleotides is well studied. The synthesis of the 64 possible ribotrinucleotides, derived from the four major ribomononucleotides has been done. Additional studies on the preparation of nucleotides and dinucleoside phosphates by the anhydronucleoside method have been reported. Reaction of 2 ′ , 3 ′ -O-isopropylidene inosine with phosphorus trichloride in acetone solution followed by an aqueous treatment and removal of the blocking group gave 5 ′ -IMP in a 91% yield. This reaction is applicable to other nucleoside isopropylidene derivatives.