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Updated: Feb 10, 2026

Rapid One-step Enzymatic Synthesis and All-aqueous Purification of Trehalose Analogues
Published on: February 17, 2017
Gemcitabine analogues with 4-N-alkyl chain modified with fluoromethyl ketone group
Cesar Gonzalez1, Maria de Cabrera, Stanislaw F Wnuk1
1a Department of Chemistry and Biochemistry , Florida International University , Miami , Florida , United States.
Abstract:
Gemcitabine analogues with a lipophilic 4-N-alkyl chain bearing a terminal β-keto sulfonate moiety suitable for fluorination compatible with 18F-radiolabeling have been explored. Displacement of p-toluenesulfonylamino in protected 4-N-tosylgemcitabine with 1-amino-10-undecene gave 4-N-(10-undecenyl)-3',5'-di-O-benzoyl-2'-deoxy-2',2'-difluorocytidine. Oxidation of the terminal double bond in the latter with OsO4/NMO afforded 4-N-(10,11-dihydroxyundecanyl) derivative. Regioselective sulfonation of primary hydroxyl followed by oxidation of secondary hydroxyl with Collin's reagent yielded desired β-keto sulfonate analogues 8 or 9. Subsequent displacement of the mesylate or tosylate group with KF in the presence of Kryptofix 2.2.2. or 18-crown-6 ether followed by deprotection with NH3/MeOH gave 4-N-(11-fluoro-10-oxoundecanyl)-2'-deoxy-2',2'-difluorocytidine 11.
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