The molecule is a glutathione derivative in which the thiol hydrogen of glutathione is replaced by a 2-methyl-1-oxobut-3-en-2-yl group. It is a conjugate acid of a S-(2-methyl-1-oxobut-3-en-2-yl)glutathione(1-).
(2S)-2-amino-5-[[(2R)-1-(carboxymethylamino)-3-(2-methyl-1-oxobut-3-en-2-yl)sulfanyl-1-oxopropan-2-yl]amino]-5-oxopentanoic acid