Solid-Phase Synthesis of the Blood Group H Determinant

5 SOLID-PHASE SYNTHESIS OF THE BLOOD GROUP H DETERMINANT 

6 SOLID SUPPORT GLYCAL ASSEMBLY VIA TfflOETHYL GLYCOSYL DONORS 

7 SOLID SUPPORT ASSEMBLY VIA THIOETHYL 2-AMIDOGLYCOSYL DONORS 

It was known from solution-based studies that an iodonium electrophile adds to the glycal linkage, in the presence of a sulfonamide, in a transdiaxial fashion.24 This results in formation of a 1 -a-sulfonamido-2-p-iodo product. Furthermore, displacement of iodine can be induced by nucleophilic attack of a thiolate nucleophile 

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