272
2
General Synthetic Methods
should help the reader solve any problems faced in their laboratories connected with planning
and execution of the synthesis of optically pure targets.
Keywords
Anhydrosugars; Synthesis; Sugar oxiranes; 1,2-Sugar epoxides; 1,6-Anhydrosugars;
Rearrangement
Abbreviations
AZT
3-azidothymidine
DET
diethyl tartrate
DIAD
di-isopropyl azodicarboxylate
DMDO dimethyldioxirane
IDCP
iodonium dicollidine perchlorate
LNA
locked nucleic acids
MCPBA m-chloroperbenzoic acid
OTs
toluene-p-sulfonate
RCM
ring closing metathesis
RNA
ribonucleic acid
THF
tetrahydrofuran
THP
tetrahydropyran
TPP
triphenylphosphine
1 Introduction
The material presented in this chapter describes the concise methodology of the preparation
of anhydrosugars and their application in synthesis, updating the chapters published in the
last edition [1,2]. However, basic information from the earlier edition is also included here
allowing the reader to follow the present text more easily. Therefore, citation to this data refers
(mostly) to the previously published chapters and not to original papers.
The anhydrosugars are an important class of saccharides, the synthesis and properties of which
are described in many monographs [3,4,5,6,7]. Such derivatives are used for the preparation of
modified carbohydrates (including C-glycosides) and complex enantiomerically pure products
in which the chirality of the parent sugar is transferred to the target (‘chiron approach’ [8]).
Many compounds from this class are also components of biologically active products. Anhydrosugars (also called ‘intramolecular anhydrides’) are derivatives that formally arise from
elimination of the molecule of water from the parent carbohydrate. Various carbon atoms may
be engaged in this formal process, thus providing different classes of anhydrosugars [3]. Generally, they belong to two main groups in which: (1) the anomeric carbon atom is involved in
the anhydro structure and (2) the anhydro linkage is built between other carbon atoms of the
sugar ( > Fig. 1). These two classes of compounds will be described separately.
To construct the anhydro skeleton in the sugar molecule standard synthetic methods, used
for the formation of ‘normal’ heterocyclic derivatives, are applicable [4,5]. Generally, one
of the hydroxyl groups of the diol (from which the anhydro ring is formed) is activated (by
2
General Synthetic Methods
should help the reader solve any problems faced in their laboratories connected with planning
and execution of the synthesis of optically pure targets.
Keywords
Anhydrosugars; Synthesis; Sugar oxiranes; 1,2-Sugar epoxides; 1,6-Anhydrosugars;
Rearrangement
Abbreviations
AZT
3-azidothymidine
DET
diethyl tartrate
DIAD
di-isopropyl azodicarboxylate
DMDO dimethyldioxirane
IDCP
iodonium dicollidine perchlorate
LNA
locked nucleic acids
MCPBA m-chloroperbenzoic acid
OTs
toluene-p-sulfonate
RCM
ring closing metathesis
RNA
ribonucleic acid
THF
tetrahydrofuran
THP
tetrahydropyran
TPP
triphenylphosphine
1 Introduction
The material presented in this chapter describes the concise methodology of the preparation
of anhydrosugars and their application in synthesis, updating the chapters published in the
last edition [1,2]. However, basic information from the earlier edition is also included here
allowing the reader to follow the present text more easily. Therefore, citation to this data refers
(mostly) to the previously published chapters and not to original papers.
The anhydrosugars are an important class of saccharides, the synthesis and properties of which
are described in many monographs [3,4,5,6,7]. Such derivatives are used for the preparation of
modified carbohydrates (including C-glycosides) and complex enantiomerically pure products
in which the chirality of the parent sugar is transferred to the target (‘chiron approach’ [8]).
Many compounds from this class are also components of biologically active products. Anhydrosugars (also called ‘intramolecular anhydrides’) are derivatives that formally arise from
elimination of the molecule of water from the parent carbohydrate. Various carbon atoms may
be engaged in this formal process, thus providing different classes of anhydrosugars [3]. Generally, they belong to two main groups in which: (1) the anomeric carbon atom is involved in
the anhydro structure and (2) the anhydro linkage is built between other carbon atoms of the
sugar ( > Fig. 1). These two classes of compounds will be described separately.
To construct the anhydro skeleton in the sugar molecule standard synthetic methods, used
for the formation of ‘normal’ heterocyclic derivatives, are applicable [4,5]. Generally, one
of the hydroxyl groups of the diol (from which the anhydro ring is formed) is activated (by