Vitamin U
S-methyl-L-methioninate is a sulfonium betaine that is a conjugate base of S-methyl-L-methionine obtained by the deprotonation of the carboxy group. It is a sulfonium betaine and a methyl-L-methionine. It is functionally related to a L-methioninate. It is a conjugate base of a S-methyl-L-methionine.