Crystal structures of 1-hydroxy-4-propyloxy-9,10-anthraquinone and its acetyl derivative

Abstract

1-Hydroxy-4-propyloxy-9,10-anthraquinone, C17H14O4, (I), and its acetyl derivative, 4-acetyloxy-4-propyloxy-9,10-anthraquinone, C19H16O5, (II), were synthesized from the commercially available dye quinizarin. In both compounds, the anthraquinone frameworks are close to planarity. There is a large difference in the conformation of the propyloxy group; the molecule of (I) adopts agaucheconformation [O—C—C—C = −64.4 (2)°], although the molecule of (II) takes atrans-planar conformation (zigzag) [O—C—C—C = 176.1 (3)°]. In the molecule of (I), there is an intramolecular O—H...O hydrogen bond. In both crystals, the molecules are linked by C—H ...O hydrogen bonds. A difference in the molecular arrangements of (I) and (II) is found along the stacking directions.

Crystal structure and Hirshfeld surface analysis of 3,4-dihydro-2H-anthra[1,2-b][1,4]dioxepine-8,13-dione

“…Anthraquinone derivatives, which are extracted from the seeds of the Rubiaceae family of shrubs, include alizarin (1,2dihydroxyanthraquinone; C 14 H 8 O 4 ) and other polycyclic aromatic hydrocarbons. The colour of anthraquinone-based compounds can be modified by the type and position of the substituents attached to the anthraquinone nucleus (Nakagawa et al 2017;Cheuk et al, 2015;Tonin et al, 2017). Besides their application as pigments or dyes in textile, photographic, cosmetic and other industries (Wang et al, 2011), anthraquinone derivatives have been used for centuries for medical applications, for example, as laxatives (Oshio et al, 1985), antioxidants (Yen et al, 2000), antimicrobial (Xiang et al, 2008;Yadav et al, 2010) and anitiviral (Alves et al, 2004) agents.…”