Concept explainers
Interpretation:
The reason for the susceptibility of nucleosides to acidic hydrolysis and the mechanism of this hydrolysis is to be explained.
Concept introduction:
舧 Electrophiles are electron-deficient species, which has positive or partially positive charge. Lewis acids are electrophiles, which accept electron pair.
舧 Nucleophiles are electron-rich species, which has negative or partially negative charge. Lewis bases are nucleophiles, which donate electron pair.
舧 A nucleoside consists of a nucleobase (also termed as nitrogenous base) and a five-carbon sugar (either ribose or deoxyribose).
舧 A
舧 In a nucleoside, the anomeric carbon is linked through a glycosidic bond to the N9 of a purine or N1 of a pyrimidine.
舧 Examples of nucleosides include cytidine, uridine, adenosine, guanosine and thymidine.
舧 Sugar (ribose/deoxyribose) and nitrogenous bases are linked through N-glycosidic bonds.
舧 These glycosidic bonds are formed by condensation reaction of first carbon of sugar molecule with the nitrogen atom
舧 This particular glycosidic bond is stable in basic solutions, but readily hydrolyzes in the presence of acids.
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Organic Chemistry, 12e Study Guide/Student Solutions Manual
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