Synthesis and Spectroscopic Characterization of [5-13C]- and [6-13C]Ubiquinone-10 for Studies of Bacterial Photosynthetic Reaction Centers

Abstract

This paper presents the synthesis and characterization by mass spectrometry and NMR spectroscopy of [2-13 C]-and [3-13 C]ubiquinone-0 and of [5-13 C]-and [6-13 C]ubiquinone-10. A scheme based on the synthetic approach to [5-13 C]ubiquinone-10 has been worked out for the synthesis of ubiquinones 13 C-labeled at any individual position and at every combination of positions in the quinone ring. The [5-13 C]-and [6-13 C]ubiquinone-10 isotopomers were incorporated

Antioxidant Properties of Natural and Synthetic Chromanol Derivatives: Study by Fast Kinetics and Electron Spin Resonance Spectroscopy

“…The structures of 6 and 7 have been confirmed by 1 H and 13 C NMR. The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, ubichromenol-1, ubichromenol-6, and the polyprenyl chain of UQ-10 …”

“…The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, 28 ubichromenol-1, 27 ubichromenol-6, 29 and the polyprenyl chain of UQ-10. 30 For transport processes in biological systems, the distribution of drugs between the aqueous phase and lipid membranes is of importance. Therefore, the lipophilicity of all compounds was assessed both by a theoretical approach and by experimental measurement of the octanol/water partition coefficients (P).…”

Antioxidant Properties of Natural and Synthetic Chromanol Derivatives: Study by Fast Kinetics and Electron Spin Resonance Spectroscopy

“…The structures of 6 and 7 have been confirmed by 1 H and 13 C NMR. The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, ubichromenol-1, ubichromenol-6, and the polyprenyl chain of UQ-10 …”

“…The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, 28 ubichromenol-1, 27 ubichromenol-6, 29 and the polyprenyl chain of UQ-10. 30 For transport processes in biological systems, the distribution of drugs between the aqueous phase and lipid membranes is of importance. Therefore, the lipophilicity of all compounds was assessed both by a theoretical approach and by experimental measurement of the octanol/water partition coefficients (P).…”

Short Syntheses of some ‘Decalin‐1,8‐diones’ and their Derivatives: Breaking the Pretended Symmetry

“…With 3,3,5,5-tetramethylcyclohexanone [19] (S8) as a model, the δ av values of C(2) and C(3) in 6b/6b' are also somewhat lower through averaging, whereas the C(4) values of 6b and S8 are almost equal. The observed δ av (C(1)) = 196.4 ppm of 6b/6b' is rather close to the limiting value of δ lim = 198.9 ppm in the model [20] S2; this and the larger difference Δδ av = δ av (C(1)) -δ av (C(8)) = 12.8 ppm point to (but do not quantify) a preponderant fraction of 6b along with 6b' in Scheme 5. However, the limiting NMR data of 6a, 6a', 6b, and 6b' must be estimated from constitutionally more similar model compounds as follows.…”

Tumor Cell Proliferation and Cyclooxygenase Inhibitory Constituents in Horseradish (Armoracia rusticana) and Wasabi (Wasabia japonica)

“…The hexane extract of wasabi rhizomes was purified by chromatographic methods and afforded α-tocopherol and ubiquinone-10 which were not active in our assays. Their structures were identified by NMR spectroscopic analyses and further confirmed by comparison with published spectral data ( , ).…”

Antioxidant Properties of Natural and Synthetic Chromanol Derivatives: Study by Fast Kinetics and Electron Spin Resonance Spectroscopy

“…The structures of 6 and 7 have been confirmed by 1 H and 13 C NMR. The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, ubichromenol-1, ubichromenol-6, and the polyprenyl chain of UQ-10 …”

“…The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, 28 ubichromenol-1, 27 ubichromenol-6, 29 and the polyprenyl chain of UQ-10. 30 For transport processes in biological systems, the distribution of drugs between the aqueous phase and lipid membranes is of importance. Therefore, the lipophilicity of all compounds was assessed both by a theoretical approach and by experimental measurement of the octanol/water partition coefficients (P).…”

Short Syntheses of some ‘Decalin‐1,8‐diones’ and their Derivatives: Breaking the Pretended Symmetry

“…With 3,3,5,5-tetramethylcyclohexanone [19] (S8) as a model, the δ av values of C(2) and C(3) in 6b/6b' are also somewhat lower through averaging, whereas the C(4) values of 6b and S8 are almost equal. The observed δ av (C(1)) = 196.4 ppm of 6b/6b' is rather close to the limiting value of δ lim = 198.9 ppm in the model [20] S2; this and the larger difference Δδ av = δ av (C(1)) -δ av (C(8)) = 12.8 ppm point to (but do not quantify) a preponderant fraction of 6b along with 6b' in Scheme 5. However, the limiting NMR data of 6a, 6a', 6b, and 6b' must be estimated from constitutionally more similar model compounds as follows.…”

Tumor Cell Proliferation and Cyclooxygenase Inhibitory Constituents in Horseradish (Armoracia rusticana) and Wasabi (Wasabia japonica)

“…The hexane extract of wasabi rhizomes was purified by chromatographic methods and afforded α-tocopherol and ubiquinone-10 which were not active in our assays. Their structures were identified by NMR spectroscopic analyses and further confirmed by comparison with published spectral data ( , ).…”

Antioxidant Properties of Natural and Synthetic Chromanol Derivatives: Study by Fast Kinetics and Electron Spin Resonance Spectroscopy

“…The structures of 6 and 7 have been confirmed by 1 H and 13 C NMR. The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, ubichromenol-1, ubichromenol-6, and the polyprenyl chain of UQ-10 …”

“…The peak assignments are in agreement with chemical shifts reported for ubichromanol-0, 28 ubichromenol-1, 27 ubichromenol-6, 29 and the polyprenyl chain of UQ-10. 30 For transport processes in biological systems, the distribution of drugs between the aqueous phase and lipid membranes is of importance. Therefore, the lipophilicity of all compounds was assessed both by a theoretical approach and by experimental measurement of the octanol/water partition coefficients (P).…”

Short Syntheses of some ‘Decalin‐1,8‐diones’ and their Derivatives: Breaking the Pretended Symmetry

“…With 3,3,5,5-tetramethylcyclohexanone [19] (S8) as a model, the δ av values of C(2) and C(3) in 6b/6b' are also somewhat lower through averaging, whereas the C(4) values of 6b and S8 are almost equal. The observed δ av (C(1)) = 196.4 ppm of 6b/6b' is rather close to the limiting value of δ lim = 198.9 ppm in the model [20] S2; this and the larger difference Δδ av = δ av (C(1)) -δ av (C(8)) = 12.8 ppm point to (but do not quantify) a preponderant fraction of 6b along with 6b' in Scheme 5. However, the limiting NMR data of 6a, 6a', 6b, and 6b' must be estimated from constitutionally more similar model compounds as follows.…”

Tumor Cell Proliferation and Cyclooxygenase Inhibitory Constituents in Horseradish (Armoracia rusticana) and Wasabi (Wasabia japonica)

“…The hexane extract of wasabi rhizomes was purified by chromatographic methods and afforded α-tocopherol and ubiquinone-10 which were not active in our assays. Their structures were identified by NMR spectroscopic analyses and further confirmed by comparison with published spectral data ( , ).…”