title: N(3)-protection of thymidine with Boc for an easy synthetic access to sugar-alkylated nucleoside analogs.
abstract: The use of Boc as a nucleobase-protecting group in the synthesis of sugar-modified thymidine analogs is reported. Boc was easily inserted at N(3) by a simple and high-yielding reaction and found to be stable to standard treatments for the removal of Ac and (t) BuMe(2) Si (TBDMS) groups, as well as to ZnBr(2) -mediated 4,4'-dimethoxytrityl (DMTr) deprotection. Boc Protection proved to be completely resistant to the strong basic conditions required to regioselectively achieve O-alkylation, therefore, providing synthetic access to a variety of sugar-alkylated nucleoside analogs. To demonstrate the feasibility of this approach, two 3'-O-alkylated thymidine analogs have been synthesized in high overall yields and fully characterized.
authors.affiliation: Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, via Cintia, 4, I-80126 Napoli.
authors.forename: Luca
authors.initials: L
authors.lastname: Simeone
authors.forename: Lorenzo
authors.initials: L
authors.lastname: De Napoli
authors.forename: Daniela
authors.initials: D
authors.lastname: Montesarchio
mesh_terms: D000478:Alkylation; D002241:Carbohydrates / Q000737:chemistry*; D005563:Formic Acid Esters / Q000737:chemistry*; D008956:Models, Chemical; D009705:Nucleosides / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism; D013936:Thymidine / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D005563:Formic Acid Esters; D009705:Nucleosides; C000345:t-butyloxycarbonyl group; D013936:Thymidine