ABSTRACT
The importance of dendritic carbohydrates and polyhydroxyl clusters in biochemical processes such as reaction site recognition, anti-gene/antibody reactions, cell-tocell communication, and regulatory effects in cell growth and protein assimilation is well established.2-12 Because of their mimetic characteristics, C-glycosyl compounds have gained appreciable consideration as anticancer and anti-in—ammatory drugs.13,14 Glycals have been used in the synthesis of such C-glycosyl compounds. Ever since Emil Fischer and Karl Zach discovered the glycals in 1913 and published on the subject in the following years,15-18 this class of carbohydrates has attracted
Experimental Methods ........................................................................................... 160 General Methods ............................................................................................... 160
General Method for the Dimerization of Glycals ......................................... 161 1,3,4,6-Tetra-O-Acetyl-2-C-(4,6-Di-O-Acetyl-2,3Dideoxy-α-d-Erythro-Hex-2-Enopyranosyl)-2-Deoxy-α/β-dGlucopyranose (2a, 2b) ................................................................................ 162
Acknowledgments .................................................................................................. 164 References .............................................................................................................. 166
attention of many chemists. Glycals19 have become very versatile synthons in carbohydrate chemistry, as demonstrated by the assembly of complex oligosaccharides and combinatorial libraries thereof.20-22 Glycals are 1,5-(or 1,4)-anhydro-2-deoxy-1enitols, structures-type A and B (Figure 16.1); R, R′, and R″ are most often oxygen functions but can also include branches or deoxy side chains.
