33. Physical properties of anthraquinone and its derivatives. Part I. Infrared spectra

Anthraquinone ß-D-glucoside from Cassia grandis

“…A spot of the aglycon on filter paper, sprayed with glacial AcOH, was viewed under UV light: appearance of characteristic fluorescence indicated the presence of 1,4-dihydroxy system (Rastrick et al, 1934) which was also supported by absorption at 482 nm in the visible region of UV spectrum and the peak at 1625 cm -1 in the IR spectrum (Thomson, 1971). A sharp and strong IR peak at 1600 cm -1 suggested that both carbonyl groups were chelated with hydroxyl groups (Bloom et al, 1959). IR peak at 2940 cm -1 and 2880 cm -1 indicated the presence of methoxyl and C-methyl groups, respectively.…”

Influence of cetophenolic and diphenolic intramolecular hydrogen bonding on the chromatographic and spectroscopic properties of hydroxyanthraquinones

“…Thus, the C]O stretching vibration is shifted to lower frequencies by the modification of the bond force constant induced by the electronic delocalisation. Indeed, previous works [26] show a diminution of free C]O stretching vibration wavenumber from 1675 cm À1 for anthraquinone to 1625 cm À1 for its amino substituted derivates. This phenomenon is consequent to the presence of amino group that supports electronic delocalisation.…”

Separation of Historical Dyes Using Capillary Electrophoresis With Laser-Induced Fluorescence Detection

“…A number of instrumental techniques have been used for studying natural dyes including infrared, [2] Raman spectroscopy, [3] and thin layer chromatography. [4] In the last 20 years separation techniques and, in particular, those utilizing gas chromatography (GC) and high performance liquid chromatography (HPLC) have been used extensively for identifying dyes in historical objects such as textiles and painted materials.…”