T R Rajagopalan
Articles written in Proceedings – Section A
Volume 44 Issue 6 December 1956 pp 418-422
Starting from chrysophanol and frangula-emodin the corresponding ω-hydroxy compounds, alœ-emodin and citreorosein have been prepared adopting the N-bromosuccinimide method. Partial methylation of frangulaemodin to physcion is effected most conveniently by the methyl sulphatepotassium carbonate method. Physcion can be demethylated directly to frangula-emodin by long boiling with hydrobromic acid.
Volume 49 Issue 1 January 1959 pp 1-5
A sample of
Volume 49 Issue 4 April 1959 pp 234-240
2-Methylanthraquinones with the 1∶4-dihydroxy system are conveniently prepared by the persulphate oxidation of the intermediate benzoylbenzoic acids and subsequent ring closure. 2-Methylquinizarin, islandicin and cynodontin have been prepared by this method as typical examples.