Organic Chemistry of Nucleic Acids: Part B

5 Substitutions and Additions in the Heterocyclic Rings of the Bases of Nucleic Acids and their Derivatives.- I. Introduction.- II. Substitution and addition reactions at carbon atoms.- 1. Halogenation.- 2. Nitration.- 3. Hydroxymethylation, aminomethylation, and chloromethylation.- 4. Reactions with diazonium salts.- 5. Reactions with N-arylhydroxylamines and their derivatives.- 6. Isotopic exchange of hydrogen atoms.- 7. Addition reactions at the C5-C6 double bond of pyrimidine derivatives.- 8. Reduction.- 9. Reactions with nucleophilic reagents without rupture of the ring.- III. Substitutionsand additions reaction at the nitrogen atoms.- 1. Interaction with alkylating agents.- 2. Interaction with reagents containing polarized C=C bonds.- 3. Interaction with reagents containing C= N bonds.- 4. Interaction with reagents containing C= O groups.- 5. Oxidation by peroxides.- 6 Reactions of Exocyclic Substituents of the Bases of Nucleic Acids and their Derivatives.- I. Introduction.- II. Substitution reactions at the nitrogen atom of an exocyclic amino group.- 1. N-Acylation.- 2. Reaction with aldehydes.- 3. Reaction with nitrous acid.- 4. Other substitutions in the amino group.- III. Substitutions at exocyclic oxygen and sulphur atoms.- 1. O-alky latio n and the formation of cyclonucleosides.- 2. S-alkylation of thiopyrimidine derivatives.- 3. Oxidation of thiopyrimidine derivatives.- 7 Reactions Involving the Cleavage or Regrouping of Heterocyclic Rings of the Bases of Nucleic acids and their Derivatives.- I. Introduction.- II. Reactions of cleavage and rearrangement of the rings by the action of nucleophilic agents.- 1. Cleavage of the imidazole ring in purine derivatives.- 2. Cleavage of the pyrimidine ring in purine derivatives.- 3. Rearrangement of 1-N-alkyladenine derivatives into 6-exo N-alkyl compounds.- 4. Opening and rearrangement of the ring in pyrimidine derivatives.- III. Cleavage by the action of hydrazine.- IV. Cleavage by the action of hydroxylamine.- V. Cleavage of rings by the action of potassium permanganate and osmium tetroxide.- VI. Cleavage by the action of peroxide derivatives.- 8 Hydrolysis of N-Glycosidic Bonds in Nucleosides, Nucleotides and their Derivatives.- I. Introduction.- II. Hydrolysis of N-glycosidic bonds catalyzed by acids 425 1. Effect of structural factors on the kinetics of hydrolysis of pyrimidine derivatives.- 2. Effect of structural factors on the kinetics of hydrolysis of purine derivatives.- 3. Acid hydrolysis of N-glycoside bonds in polynucleotides.- III. Hydrolysis of N-glycosidic bonds in pyrimidine deoxyribonucleosides, not catalyzed by acids or bases.- IV. Hydrolysis of N-glycosidic bonds in an alkaline medium.- V. Other reactions leading to cleavage of glycosidic bonds.- 9 Reactions of the Carbohydrate Residues of Nucleic Acids.- I. Introduction.- II. Acylation of hydroxyl groups of carbohydrate residues.- 1. Acylation.- 2. Aminoacylation.- 3. Preparation of esters with inorganic acids.- III. Alkylation of the hydroxyl groups of carbohydrate residues.- 1. Reaction with diazomethane.- 2. Reaction with alkyl halides.- 3. Reaction with triarylchloromethanes.- IV. Reactions of hydroxyl groups of carbohydrate residues with vinyl esters.- V. Reactions of hydroxyl groups of carbohydrate residues with carbonyl compounds and with their derivatives.- VI. Oxidation of carbohydrate residues.- 1. Oxidation of an isolated hydroxyl group.- 2. Oxidation of the cis-glycol group in ribo-derivatives.- 10 Cleavage of Phosphoester Bonds and some other Reactions of Phophate Groups of Nucleic Acids and their Derivatives.- I. Introduction.- II. Reactions with cleavage of P-O bonds.- 1. Hydrolysis of phosphomonoester bonds in ribonucleotides and degradation of RNA to nucleosides.- 2. Hydrolysis of phosphoester bonds in ribonucleoside cyclic phosphates.- 3. Hydrolysis of phosphodiester bonds in polynucleotides.- III. Reactions with rupture of C-0 bonds.- 1. Clea vage of phosphoester bonds after remo