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Iodine monochloride facilitated deglycosylation, anomerization, and isomerization of 3-substituted thymidine analogues.

ABSTRACT: The reaction of thymidine, 3-mono-, and 3,3',5'-trialkylsubstitued thymidine analogues with iodine monochloride (ICl) was investigated. Treatment with ICl resulted in rapid deglycosylation, anomerization, and isomerization of thymidine and 3-substituted thymidine analogues under various reaction conditions leading to the formation of the nucleobases as the major products accompanied by minor formation of ?-furanosidic-, ?-pyranosidic-, and ?-pyranosidic nucleosides. On the other hand, 3,3',5'-trisubstitued thymidine analogues were only deglycosylated and anomerized. These results are similar to those observed for the acidic hydrolysis of the glycoside bond in nucleosides, but were presumably caused by the Lewis acid character of an iodine electrophile.

SUBMITTER: Khalil A

PROVIDER: S-EPMC4266569 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Iodine monochloride facilitated deglycosylation, anomerization, and isomerization of 3-substituted thymidine analogues.

Khalil Ahmed A Ishita Keisuke K Ali Tehane T Tiwari Rohit R Riachy Ramy R Toppino Antonio A Hasabelnaby Sherifa S Sayfullin Naum N Oliver Allen G AG Gallucci Judith J Huang Zhenguo Z Tjarks Werner W

Nucleosides, nucleotides & nucleic acids 20140101 12

The reaction of thymidine, 3-mono-, and 3,3',5'-trialkylsubstitued thymidine analogues with iodine monochloride (ICl) was investigated. Treatment with ICl resulted in rapid deglycosylation, anomerization, and isomerization of thymidine and 3-substituted thymidine analogues under various reaction conditions leading to the formation of the nucleobases as the major products accompanied by minor formation of α-furanosidic-, α-pyranosidic-, and β-pyranosidic nucleosides. On the other hand, 3,3',5'-tr ...[more]

PMID: 25372994

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