title: Regiodefined synthesis of brominated hydroxyanthraquinones related to proisocrinins.
abstract: Dibromobenzoisofuranone 12, synthesized in six steps, was regiospecifically annulated with 5-substituted cyclohexenones 13/36 in the presence of LiOt-Bu to give brominated anthraquinones 14/38 in good yields. Darzens condensation of 30 was shown to give chain-elongated anthraquinone 32. Alkaline hydrolysis of 38 furnished 39 representing desulfoproisocrinin F.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur- 721302, India.
authors.forename: Joyeeta
authors.initials: J
authors.lastname: Roy
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur- 721302, India.
authors.forename: Tanushree
authors.initials: T
authors.lastname: Mal
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur- 721302, India.
authors.forename: Supriti
authors.initials: S
authors.lastname: Jana
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur- 721302, India.
authors.forename: Dipakranjan
authors.initials: D
authors.lastname: Mal
keywords: Darzens condensation; Hauser annulation; brominated anthraquinones; proisocrinins