Fmoc-N',N',N'-trimethyl-L-lysine chloride

CAS 201004-29-7

Three methyl groups on lysine's side-chain nitrogen create a quaternary ammonium feature that can be placed precisely in a synthetic peptide. Fmoc-trimethyl-L-lysine chloride makes that experiment possible: Fmoc temporarily manages the amino group used for assembly, while the methylated side chain is intended to remain. Chloride is the counterion, not a carbon-bound chlorine substituent. In histone research, defined peptides help compare modification states and sequence contexts, including recognition on peptide arrays. Those arrays are models rather than complete chromatin systems, so binding requires careful interpretation. The reagent makes an epigenetic question chemically concrete by specifying one protein-side-chain modification, without changing the DNA base sequence or implying that every trimethyllysine site carries the same biological message. Lower methylation states also differ in their nitrogen substitution pattern.