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Sebastian D, Satishkumar S, Pradhan P, Yang L, Lakshman MK. General Approach to N6,C5'-Difunctionalization of Adenosine. J Org Chem 2021; 87:18-39. [PMID: 34905365 DOI: 10.1021/acs.joc.1c01587] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Among the C6-halo purine ribonucleosides, the readily accessible 6-chloro derivative has been known to undergo slow SNAr reactions with amines, particularly aryl amines. In this work, we show that in 0.1 M AcOH in EtOH, aryl amines react quite efficiently at the C6-position of 2',3',5'-tri-O-(t-BuMe2Si)-protected 6-chloropurine riboside (6-ClP-riboside), with concomitant cleavage of the 5'-silyl group. These two-step processes proceeded in generally good yields, and notably, reactions in the absence of AcOH were much slower and/or lower yielding. Corresponding reactions of 2',3',5'-tri-O-(t-BuMe2Si)-protected 6-ClP-riboside with alkyl amines proceeded well but without desilylation at the primary hydroxyl terminus. These differences are likely due to the acidities of the ammonium chlorides formed in these reactions, and the role of AcOH was not desilylation but possibly only purine activation. With 50% aqueous TFA in THF at 0 °C, cleavage of the 5'-silyl group from 2',3',5'-tri-O-(t-BuMe2Si)-protected N6-alkyl adenosine derivatives and from 6-ClP-riboside was readily achieved. Reactions of the 5'-deprotected 6-ClP-riboside with alkyl amines proceeded in high yields and under mild conditions. Because these complementary methodologies yielded N6-aryl and -alkyl adenosine derivatives containing a free 5'-hydroxyl group, a variety of product functionalizations were undertaken to yield N6,C5'-doubly modified nucleoside analogues.
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Affiliation(s)
- Dellamol Sebastian
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, New York 10031, United States.,The Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, United States
| | - Sakilam Satishkumar
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, New York 10031, United States
| | - Padmanava Pradhan
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, New York 10031, United States
| | - Lijia Yang
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, New York 10031, United States
| | - Mahesh K Lakshman
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, New York 10031, United States.,The Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, United States
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Harder M, Schäfer E, Kümin T, Illarionov B, Bacher A, Fischer M, Diederich F, Bernet B. 8-Substituted, syn-Configured Adenosine Derivatives as Potential Inhibitors of the Enzyme IspE from the Non-Mevalonate Pathway of Isoprenoid Biosynthesis. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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