Absolute configuration assignment of caffeic acid ester derivatives from Tithonia diversifolia by vibrational circular dichroism: the pitfalls of deuteration - Ccana-Ccapatinta, Gari V.; Sampaio, Bruno L.; Santos Júnior, Fernando M. dos; Batista Júnior, João M.; Costa, Fernando Batista da (Tetrahedron: Asymmetry, 2017)