Conformational analysis of difluoromethylornithine: factors influencing its gas-phase and bioactive conformations

• Matheus P. Freitas

Beilstein J. Org. Chem. 2026, 22, 237–243, doi:10.3762/bjoc.22.17

• Matheus P. Freitas Department of Chemistry, Institute of Natural Sciences, Federal University of Lavras, 37200-900, Lavras, MG, Brazil 10.3762/bjoc.22.17 Abstract Difluoromethylornithine (DFMO, eflornithine) is a fluorinated analogue of ornithine that serves both as an inhibitor of ornithine

• intermolecular interactions in biological environments. This study clarifies the electronic origin of DFMO’s gauche effect and provides insight into how local electronic factors determine the structure of fluorinated amino acid derivatives. Keywords: conformational analysis; difluoromethylornithine; gauche

• effect; hyperconjugation; Introduction Difluoromethylornithine (DFMO, in its racemic form, also known as eflornithine – Figure 1) is a fluorinated analogue of ornithine that has attracted considerable attention due to its dual relevance in medicine and structural chemistry. Clinically, DFMO has been