The molecular formula C4H6N2O2 may refer to:
- Cyanoalanine, an uncommon amino acid
- Dihydrouracil, an intermediate in the catabolism of uracil
- 2,5-Diketopiperazine
- Ethyl diazoacetate, a reagent used in organic chemistry
- Muscimol, the major psychoactive alkaloid present in many mushrooms of the genus Amanita