2-(((1-Hydroxybutan-2-yl)oxy)carbonyl)benzoic Acid-D4 is the deuterated form of 2-(((1-Hydroxybutan-2-yl)oxy)carbonyl)benzoic Acid (H956338), which is an intermediate in synthesizing Mono-2-hydroxy-n-butyl-phthalate (M547515), a metabolite of phthalate.