A NEW PROTECTING GROUP FOR THE 5′-HYDROXYL GROUP HAVING O–S SINGLE BOND OXIDATIVELY CLEAVABLE UNDER MILD CONDITIONS

Abstract

We developed a new protecting group, i.e., cis-[4-[[(4-methoxytrityl)sulfenyl]oxy]tetrahydrofuran-3-yl]oxycarbonyl (MTFOC), which could be removed under neutral conditions involving the oxidative removal of the MMTrS group followed by the self-cyclization of the resulting intermediate. The introduction of the protecting group into the 5′-hydroxyl group of a thymidine derivative and its deprotection were studied.