nor-KC2

nor-KC2 is an ionizable cationic lipid structurally related to DLin-KC2-DMA (KC2), with the C18 linoleyl chains of KC2 replaced by shorter C17 chains. Like KC2, it features two hydrophobic chains connected through a 1,3-dioxolane ring to a dimethylaminoethyl head group.

The C17 chains are derived from commercially available methyl linoleate. This enables a shorter, more streamlined synthetic route than the original preparation of KC2. Published studies indicate that nor-KC2 can provide comparable or improved nucleic acid delivery performance relative to KC2.

nor-KC2 is used in siRNA and mRNA LNP formulation and in structure–activity work on ionizable lipid design, where the dioxolane scaffold makes it a useful counterpart to the ester-linked MC3 series. As with nor-MC3, the simpler synthesis is the practical draw: it makes the lipid easier to produce consistently and to scale up when a formulation moves beyond screening quantities.