Vibrational analysis of flavin derivatives: Normal coordinate treatments of lumiflavin

Abstract

Normal coordinate calculations were carried out for lumiflavin (Lf) and isotope- or methyl-substituted derivatives of it; [3-ND]Lf, [3-NMe]Lf, [2- 13C]Lf, [4a- 13C]Lf, [5- 15N]Lf, [1, 3- 15N]Lf and [1, 3, 5- 15N]Lf. Using 69 force constants of the modified local symmetry force field, the observed resonance Raman bands and i.r. bands of these molecules could be assigned to the normal modes. The vibrational modes are represented in terms of the calculated atomic displacement vectors.