2'-O-NMA-5-Me-C (Bz) CE Phosphoramidite

2'-O-NMA-5-Me-C (Bz) CE Phosphoramidite is a 2'-modified RNA building block on a 5-methylcytosine base: 5'-O-(4,4'-dimethoxytrityl)-N4-benzoyl-5-methylcytidine with a 2'-O-[2-(methylamino)-2-oxoethyl] group and a 3'-O-(2-cyanoethyl N,N-diisopropyl)phosphoramidite. It is identified by CAS 1025783-18-9, molecular formula C50H59N6O10P, molecular weight 935.0, PubChem CID 177788710, and InChIKey OABRWFIIVWCDDM-WBHVIXSUSA-N.

Two features combine: the base is 5-methylcytosine (a permanent 5-methyl base modification, with the exocyclic amine benzoyl-protected during synthesis), and the sugar carries the 2'-O-N-methylacetamide ("NMA") group (2'-O-CH2-C(=O)-NH-CH3), a permanent 2'-O-modification. The cited 2'-modification literature is used here as background for the 2'-position modification class, not as a standalone performance claim for this catalog item. The monomer couples through a standard 3'-phosphoramidite (3'→5' linkages), the 5'-DMT is removed each cycle, and the N4-benzoyl base-protecting group is removed during final deprotection.