Methyl methanesulfonate

Methyl methanesulfonate (CAS 66-27-3) is a potent electrophilic methylating agent widely employed in organic synthesis, pharmaceutical process development, and molecular biology research. This small-molecule sulfonate ester features a highly reactive methyl group activated by the electron-withdrawing methanesulfonyl moiety, enabling efficient SN2-type alkylation of nucleophiles including amines, thiols, phenols, alcohols, and carboxylates. In medicinal chemistry, MMS serves as a critical reagent for N-methylation, O-methylation, and S-methylation transformations where precise methyl installation is required. In molecular biology, it functions as a DNA-alkylating probe for mutagenesis studies, DNA damage response research, and carcinogenesis mechanism investigations. Compared to dimethyl sulfate, MMS offers slightly reduced volatility while maintaining high reactivity, making it a preferred methylating agent for laboratory-scale reactions. It is also widely used as a chemical standard in analytical chemistry for gas chromatography (GC) and mass spectrometry (MS) method development. Manufactured under controlled conditions, it supports synthetic programs requiring reliable methyl transfer chemistry with well-defined reaction kinetics.