Abstract
The reductive opening of 2-methoxyethylidene acetals of vicinal diols in uridine and 1,4-anhydro-d -ribitol in the presence of TiCl4 and Et3 SiH was investigated. The 3′-O -(2-methoxyethyl) ether of uridine and the 2′-O -(2-methoxyethyl) ether of 1,4-anhydro-d -ribitol were isolated and characterized. The results were rationalized based on coordination effects involving proximal substituents.
Key words
acetal - reductive opening - nucleoside - antisense
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