DMT-2'O-TBDMS-rA(bz) Phosphoramidite

N-Benzoyl-5'-O-(4,4-Dimethoxytrityl)-2'-O-[(tert-butyl)dimethylsilyl]adenosine-3'-(2-cyanoethyl-N,N-diisopropyl)phosphoramidite can be used as Organic synthesis intermediates and pharmaceutical intermediates are mainly used in laboratory research and development processes and chemical production processes.

DMT-2''O-TBDMS-rA(bz) Phosphoramidite (DMT-2'O-TBDMS-rA(bz) Phosphoramidite) is a 2''-O-Protected ribonucleoside phosphoramidite used as a key raw material for the automated solid-supported synthesis of oligonucleotide-based drugs. It is also used to synthesize 2''-O-guanidinopropyl-modified nucleoside phosphoramidites to incorporate into siRNAs targeting hepatitis B virus.

To a solution of 72 (12.0 g, 15.2 mmoi) in DIPEA (15 ml) and DCM (30 mL) is added DMAP (744 mg, 6.09 rnrnol) and 2cyanoethyl JV.Ndiisopropylchlorophosphoramidite (5.41 g, 22.9 rnmoi) at 25 ℃. After stirring for 2 hours, the mixture is purified directly by basic silica gel column chromatography (EAIPE 1/4 toi/1) to give DMT-2'O-TBDMS-rA(bz) Phosphoramidite as a white solid (13.0 g. 86% yield)

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