The Systematic Identification of Flavonoids

ISBN-13: 9783642884603 / Angielski / Miękka / 2012 / 354 str.

T. J. Mabry; K. R. Markham; M. B. Thomas

Opis

About 1958, the late Professor R. E. ALSTON and Professor B. L. TURNER, both of the Department ofBotany, The University ofTexas at Austin, initiated a general systematic investigation ofthe legurne genus Baptisia. They found that flavonoid patterns, as revealed by two-dimensional paper chromatography, were valid criteria for the recognition of the Baptisia species and for the documentation of their numerous natural hybrids. Later, they showed that the flavonoid chemistry could be used for the analysis of gene flow among populations. At that time no attempt was made to even partially identify the flavonoids which were detected chromatographically. Neverthe1ess, it soon became apparent that the full value of the chemical data for systematic purposes required knowledge of the structures of the flavonoids. In 1962, one of us (T.J.M.) in collaboration with Drs. ALSTON and TURNER beg an the chemical analysis of the more than 60 flavonoids which had been chromatographi- cally detected in the 16 Baptisia species. In the intervening years, a number of chemists and botanists, inc1uding Drs. K. BAETCKE, B. BREHM, M. CRANMER, D. HORNE, J. KAGAN, B. KROSCHEWSKY, J. MCCLURE, H. ROSLER, and J. WALLACE, participated in the devel- opment of techniques and procedures for the rapid identification of known flavonoids and in the structure determination of new flavonoids. In addition, the flavonoid chem- istry of many plants other than Baptisia was investigated.

Spis treści

I The Isolation, Purification and Preliminary Identification of Flavonoids.- I. The Two-Dimensional Paper Chromatographic Analysis of Flavonoids.- I-1. Reagents and Materials.- I-2. Experimental Procedures for the Two-Dimensional Paper Chromatographic Analysis of Flavonoid Mixtures.- I-3. The Determination of Rf Values for Flavonoids.- I-4. The Effects of Flavonoid Structural Variations on Rf. Values.- I-5. Relationships between Spot Color and Flavonoid Structure.- I-6. The Isolation and Purification of Flavonoids by Preparative Two-Dimensional Paper Chromatography.- I-7. The One-Dimensional Paper Chromatographic Purification of a Partially Purified Flavonoid.- II. The Separation of Flavonoids by Column and Thin Layer Chromatography.- II-1. Preliminary Purification of Flavonoids in a Crude Plant Extract Using Charcoal.- II-2. The Separation of Flavonoids by Polyamide and Silica Gel Column Chromatography.- II-3. The Separation of Flavonoids by Silica Gel and Polyamide Thin Layer Chromatography.- III. The Aglycone and Sugar Analysis of Flavonoid Glycosides.- III-1. Procedures for the Acidic and Enzymatic Hydrolysis of Flavonoid Glycosides.- III-2. The Gas and Paper Chromatographic Procedures for Identifying the Sugars Obtained by Hydrolysis of Flavonoid Glycosides.- III-3. The Identification of the Aglycone and Location of the Sugar in Flavonoid Glycosides.- III-4. The Identification of the Sugars in C-Glycosylflavonoids.- II The Structure Analysis of Flavonoids by Ultraviolet Spectroscopy.- IV. Reagents and Procedures for the Ultraviolet Spectral Analysis of Flavonoids.- IV-1. Preparation of Reagent Stock Solutions and Solids.- IV-2. Procedures for Determining the Ultraviolet Absorption Spectra of Flavonoids.- V. The Ultraviolet Spectra of Flavones and Flavonols.- V-1. The UV Spectra of Flavones and Flavonols in Methanol.- V-2. The UV Spectra of Flavones and Flavonols in the Presence of NaOMe.- V-3. The UV Spectra of Flavones and Flavonols in the Presence of NaOAc.- V-4. The Detection of Ortho-dihydroxyl Groups in Flavones and Flavonols by the Effect of NaOAc/H3BO3 on the UV Spectrum.- V-5. The UV Spectra of Flavones and Flavonols in the Presence of AlCl3 and AlCl3/HCl.- V-6. Index of Ultraviolet Absorption Spectra of Flavones and Flavonols.- VI. The Ultraviolet Spectra of Isoflavones, Flavanones, and Dihydroflavonols.- VI-1. The UV Spectra of Isoflavones, Flavanones and Dihydroflavonols in Methanol.- VI-2. The UV Spectra of Isoflavones, Flavanones and Dihydroflavonols in the Presence of NaOMe.- VI-3. The UV Spectra of Isoflavones, Flavanones and Dihydroflavonols in the Presence of NaOAc.- VI-4. The Detection of A-Ring Ortho-dihydroxyl Groups in Isoflavones, Flavanones and Dihydroflavonols by the Effect of NaOAc/H3BO3 on the UV Spectrum.- VI-5. The UV Spectra of Isoflavones, Flavanones and Dihydroflavonols in the Presence of AlCl3 and AICl3/HCl.- VI-6. Index of Ultraviolet Absorption Spectra of Isoflavones, Flavanones and Dihydroflavonols.- VII. The Ultraviolet Spectra of Chalcones and Aurones.- VII-1. The UV Spectra of Chalcones and Aurones in McOH.- VII-2. The UV Spectra of Chalcones and Aurones in the Presence of NaOMe.- VII-3. The UV Spectra of Chalcones and Aurones in the Presence of NaOAc.- VII-4. The Detection of Ortho-dihydroxyl Groups in Chalcones and Aurones by the Effect of NaOAc/H3BO3 on the UV Spectrum.- VII-5. The UV Spectra of Chalcones and Aurones in the Presence of AlCl3 and AlCl3/HCl.- VII-6. Index of Ultraviolet Absorption Spectra of Chalcones and Aurones.- III The Structure Analysis of Flavonoids by Proton Nuclear Magnetic Resonance Spectroscopy.- VIII. The Determination and Interpretation of NMR Spectra of Flavonoids.- VIII-1. Introduction.- VIII-2. The Use of DMSO-d6 as Solvent for Flavonoid NMR Spectroscopy.- VIII-3. Preparation of Trimethylsilyl Ether Derivatives of Flavonoids.- VIII-4. Interpretation of the NMR Spectra of Fully and Partially Trimethylsilylated Flavonoids.- IX. The NMR Spectra of Flavonoids.- Subject-Index.