Some Key Experimental Features of a Modular Synthesis of Heparin‐Like Oligosaccharides

The key features of a modular n+2 strategy for a completely stereoselective synthesis of oligosaccharides containing the GlcN−IdoA repeating unit of the major sequence of heparin are presented and discussed in detail. These key features include the regio‐ and stereoselective synthesis of disaccharide building blocks and the reactivity of building blocks in the modular assembly process. The synthetic strategy, the effectiveness of which has previously been demonstrated by the total synthesis of four hexasaccharides and two octasaccharides, allows the size and the charge distribution of the target oligosaccharide fragments to be controlled. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003