1. APIs
  2. Levonorgestrel
  3. Metabolites

Levonorgestrel Metabolites

Name Structure Notes
3β,5α-tetrahydrolevonorgestrel structure Estrogenic activity. Significantly reduced progestational activity.
2α-hydroxylevonorgestrel structure Also present as glucuronide conjugate.
13-ethyl-4-homogonane-3,17-dione structure Also present as sulfate and glucuronide conjugates.
16β-hydroxy-3α,5β-tetrahydrolevonorgestrel structure Also present as sulfate and glucuronide conjugates.
16β-Hydroxylevonorgestrel structure Sulfate conjugate also present, as well as the sulfate conjugate of the 16α stereoisomer. Metabolite of both levonorgestrel and norgestrel.
3β,5β-tetrahydrolevonorgestrel structure Minor metabolite. Also present as a sulfate conjugate.
3α,5β-tetrahydrolevonorgestrel structure Major metabolite. Also found as sulfate and glucuronide conjugates.
3α,5α-tetrahydrolevonorgestrel structure "Much smaller" amount present than the primary metabolite 3α,5β-tetrahydrolevonorgestrel. Sulfate and glucuronide conjugates are also present. Tetrahydrometabolites of LNG are reported to show estrogenic activity in vitro.