Features Synonym: (R)-2-Amino-4-methylpentanoic acid CAS#: 61-90-5 Molecular Formula: 131.17 Molecular Weight: C₆H₁₃NO₂  

Leucine is a branched-chain α-amino acid. Leucine is classified as a hydrophobic amino acid due to its aliphatic isobutyl side chain. Leucine has been used as a molecular marker in the recovery of DNA from palaeontological samples for PCR analysis.