Autor según el artículo: M. Isabel Matheu Andrea Kövér Omar Boutureira Yolanda Díaz Sergio Castillón

Departamento: Química Analítica i Química Orgànica

Autor/es de la URV: MATHEU MALPARTIDA, MARÍA ISABEL Andrea Kövér Omar Boutureira Yolanda Díaz Sergio Castillón

Palabras clave: deoxycarbohydrates

Resumen: The preparation of challenging 2-deoxy-2-iodo-β-D-allo precursors of 2-deoxy-β-D-ribo-hexopyranosyl units and other analogues is reported using a robust olefination−cyclization−glycosylation sequence. Here, we particularly focus on tuning the stereoelectronic properties of the alkenyl sulfides intermediates in order to improve the diastereoselectivity of the cyclization step and, hence, the efficiency of the overall transformation. Phosphine oxides with the general formula Ph2P(O)CH2SR (R = t- Bu, Cy, p-MeOPh, 2,6-di-ClPh, and 2,6-di-MePh) were easily synthesized and subsequently used in the olefination reaction with 2,3,5-tri-O-benzyl-D-ribose and -D-arabinose. The corresponding sugar-derived alkenyl sulfides were submitted to a 6-endo [I+]- induced cyclization, and the resulting 2-deoxy 2-iodohexopyranosyl-1-thioglycosides were used as glycosyl donors for the stereoselective synthesis of 2-deoxy-2-iodohexopyranosyl glycosides. Among the different S-groups studied, t-Bu derivative was the best performer for the synthesis of cholesteryl 2-deoxy-2-iodomannopyranosides, whereas for the synthesis of 2-deoxy-2- iodoallopyranosides none of the derivatives here studied proved superior to the phenyl analogue previously described. Glycosylation of cholesterol with different D-allo and D-manno derivatives produced 2-deoxy-2-iodoglycosides with stereoselectivities in the same order in each case, reinforcing the involvement of an oxocarbenium ion as the common intermediate of this crucial glycosylation step.

Grupo de investigación: Síntesis Orgànica Estereoselectiva

Áreas temáticas: Química Química Chemistry

Acceso a la licencia de uso: https://creativecommons.org/licenses/by/3.0/es/

ISSN: 0022-3263

Identificador del autor: 0000-0001-5216-9260 n/a 0000-0002-0768-8309 0000-0001-5567-8108 n/a

Fecha de alta del registro: 2015-04-16

Página final: 3068

Volumen de revista: 79

Versión del articulo depositado: info:eu-repo/semantics/acceptedVersion

Enlace a la fuente original: https://pubs.acs.org/doi/10.1021/jo5001912

DOI del artículo: 10.1021/jo5001912

Entidad: Universitat Rovira i Virgili

Año de publicación de la revista: 2014

Página inicial: 3060

Tipo de publicación: Article Artículo Article