3.6 Glycal Derivatives
Waldemar Priebe* 1 , Izabela Fokt 1 , Grzegorz Grynkiewicz 2
1 M. D. Anderson Cancer Center, The University of Texas,
Houston, TX 77030, USA
2 Pharmaceutical Research Institute, Rydgiera 8, 01-793 Warsaw, Poland
wpriebe@mdanderson.org, wp@wt.net, g.grynkiewicz@ifarm.waw.pl
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700
2 Reductive Elimination of Glycosyl Halides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 701
3 Base-Catalyzed Eliminations of Glycosyl Halides to Yield 2-Oxy-hex-1-enitols . 706
4 Eliminations Induced by Alkyllithium Reagents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 709
5 Thermal Elimination of Sulfoxides and Selenoxides to Glycals . . . . . . . . . . . . . . . . . 712
6 Glycals from 2-Deoxysaccharides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 713
7 Reactions Involving 2,3-Unsaturated Saccharide-to-Glycal
and Glycal-to-GlycalRearrangements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 716
8 Cycloadditions and Cyclizations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 722
9 Preparation of exo-Glycals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 726
10 Miscellaneous Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 727
Abstract
Glycals are unsaturated sugar derivatives in which the double bond engages the anomeric
carbon atom. Such cyclic vinyl ethers are characterized by high reactivity, allowing for regioand stereoselective transformations, directly or indirectly related to glycosylation, as well as to
formation of carbon–carbon and carbon–heteroatom bonds at the anomeric center. This review
provides a systematic survey of chemical synthetic methods, by which the carbon–carbon double bond is introduced next to the ring oxygen, in an endo- or exocyclic position. Some mechanistic aspects are discussed in relation to traditional methods of glycal preparation, which rely
on elimination reactions. Glycal-to-glycal rearrangement and applications of organometallic
chemistry and heteroatom-induced transformations for syntheses and activation of glycals are
also highlighted.
Keywords
Glycal; Synthesis; Carbohydrate; Monosaccharides
In: Glycoscience. Fraser-Reid B, Tatsuta K, Thiem J (eds)
Chapter-DOI 10-1007/978-3-540-30429-6_15: © Springer-Verlag Berlin Heidelberg 2008
Waldemar Priebe* 1 , Izabela Fokt 1 , Grzegorz Grynkiewicz 2
1 M. D. Anderson Cancer Center, The University of Texas,
Houston, TX 77030, USA
2 Pharmaceutical Research Institute, Rydgiera 8, 01-793 Warsaw, Poland
wpriebe@mdanderson.org, wp@wt.net, g.grynkiewicz@ifarm.waw.pl
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700
2 Reductive Elimination of Glycosyl Halides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 701
3 Base-Catalyzed Eliminations of Glycosyl Halides to Yield 2-Oxy-hex-1-enitols . 706
4 Eliminations Induced by Alkyllithium Reagents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 709
5 Thermal Elimination of Sulfoxides and Selenoxides to Glycals . . . . . . . . . . . . . . . . . 712
6 Glycals from 2-Deoxysaccharides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 713
7 Reactions Involving 2,3-Unsaturated Saccharide-to-Glycal
and Glycal-to-GlycalRearrangements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 716
8 Cycloadditions and Cyclizations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 722
9 Preparation of exo-Glycals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 726
10 Miscellaneous Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 727
Abstract
Glycals are unsaturated sugar derivatives in which the double bond engages the anomeric
carbon atom. Such cyclic vinyl ethers are characterized by high reactivity, allowing for regioand stereoselective transformations, directly or indirectly related to glycosylation, as well as to
formation of carbon–carbon and carbon–heteroatom bonds at the anomeric center. This review
provides a systematic survey of chemical synthetic methods, by which the carbon–carbon double bond is introduced next to the ring oxygen, in an endo- or exocyclic position. Some mechanistic aspects are discussed in relation to traditional methods of glycal preparation, which rely
on elimination reactions. Glycal-to-glycal rearrangement and applications of organometallic
chemistry and heteroatom-induced transformations for syntheses and activation of glycals are
also highlighted.
Keywords
Glycal; Synthesis; Carbohydrate; Monosaccharides
In: Glycoscience. Fraser-Reid B, Tatsuta K, Thiem J (eds)
Chapter-DOI 10-1007/978-3-540-30429-6_15: © Springer-Verlag Berlin Heidelberg 2008