title: Preparative production of spinochrome E, a pigment of different sea urchin species.
abstract: A concise route to spinochrome E (1) (2,3,5,6,7,8-hexahydroxy-1,4-naphthoquinone), a pigment isolated from sea urchins of different species, has been developed starting from either commercially available 5,8-dihydroxy-1,4-naphthoquinone (11) or 2,3-dichloro-5,8-dihydroxy-1,4-naphthoquinone (12). The protocol involves 3 steps, the chlorination of either 11 or 12 to tetrachloronaphthazarin (13), the total nucleophilic substitution of the chlorine atoms in 13 by methoxy groups, and hydrolysis of tetramethyl ether14; this makes possible the preparation of the target compound in overall yields from 41 to 46%.
authors.forename: Olga P
authors.initials: OP
authors.lastname: Shestak
authors.forename: Victor Ph
authors.initials: VP
authors.lastname: Anufriev
authors.forename: Vyacheslav L
authors.initials: VL
authors.lastname: Novikov
mesh_terms: D000818:Animals; D015394:Molecular Structure; D009285:Naphthoquinones / Q000138:chemical synthesis* / Q000737:chemistry; D012617:Sea Urchins / Q000737:chemistry*
chemical_list: D009285:Naphthoquinones; C009304:spinochrome A