Chemical synthesis and some properties of 6-substituted flavins

• Published in: Biochemistry (Easton) Vol. 19; no. 12; pp. 2537 - 2544
• Main Authors: Ghisla, Sandro, Kenney, William C, Knappe, Wolfgang R, McIntire, William, Singer, Thomas P
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 10.06.1980
• Subjects: Electron Spin Resonance Spectroscopy; Flavins - chemical synthesis; Indicators and Reagents; Magnetic Resonance Spectroscopy; Mass Spectrometry; Methods; Riboflavin - analogs & derivatives; Riboflavin - chemical synthesis; Spectrophotometry; Structure-Activity Relationship
• ISSN: 0006-2960; 1520-4995
• DOI: 10.1021/bi00553a001

A number of derivatives of riboflavin and of 3-methyllumiflavin substituted in the 6 position have been synthesized starting with 6-nitro flavins, reduction to the 6-amino flavin, and diazotization, followed by reaction with the appropriate nucleophile. The absorption spectra, oxidation-reduction potentials, and the electron spin resonance spectra of the radical cationic forms of several of these synthetic compounds have been determined, including 6-S-cysteinyl-3-methyllumiflavin and 6-S-cysteinylriboflavin. The latter has been shown to be identical with the dephosphorylated form of the aminoacyl flavin isolated from trimethylamine dehydrogenase [Steenkamp, D. J., Kenney, W. C. & Singer, T. P. (1978) J. Biol. Chem. 253, 2812-2817; Steenkamp, D. J., McIntire, W., & Kenney, W. C. (1978) J. Biol. Chem. 253, 2818-2824] in regard to absorption specturm, photochemical properties, and mobility in high-voltage electrophoresis and in thin-layer chromatography. An unusually pronounced interaction between the amino group and the isoalloxazine ring system was deduced from the absorption spectra of 6-amino-3-methyllumiflavin and 6-aminoriboflavin.