Used in solid-phase oligonucleotide synthesis for the preparation of modified RNA sequences, particularly in antisense therapeutics and RNA interference technologies. The acetyl protection on the exocyclic amine of 5-methylcytidine prevents side reactions during coupling, while the DMT and TOM groups provide selective protection for the 5'-hydroxyl and 2'-hydroxyl in ribose, enabling stepwise chain elongation. The phosphoramidite moiety allows efficient coupling to the growing nucleotide chain. This compound is especially valuable in the synthesis of stabilized oligonucleotides with enhanced nuclease resistance and improved binding affinity, commonly used in diagnostic probes, gene regulation studies, and development of therapeutic nucleic acids.