[2S-[2α,5α,6β(S*)]]-6-[[(4-Hydroxyphenyl)[(3-methoxy-1-methyl-3-oxo-1-propenyl)amino]acetyl]amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic Acid-d4 is an intermediate used in the synthesis of Amoxicillin-d4 (Major), which is labelled semi-synthetic antibiotic related to Penicillin. Antibacterial.