Sodium 3-methyl-2-oxobutanoate-13C4,d4 is the deuterium and 13C labeled Sodium 3-methyl-2-oxobutanoate[1].
References
[1] Russak EM, et al. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019;53(2):211-216. DOI:10.1177/1060028018797110
α-Keto Isovaleric Acid Sodium Salt 13C4, D4 Supplier