title: Cinnamoyl shikonin.
abstract: The title compound, 1-(5,8-dihydro-1,4-dihydroxy-5,8-dioxo-2-naphthyl)-4-methylpent-3-en-1-yl cinnamate, C(25)H(22)O(6), crystallizes in space group P2(1). The phenyl ring of the cinnamate is anti to the carbonyl group of the same moiety [C-C-C-C = -175.6 (2) degrees] and is nearly parallel to the naphthyl ring system. Two six-membered rings formed by intramolecular hydrogen bonds, with O-H...O distances of 2.587 (2) and 2.589 (2) A, occur on either side of the fused ring system, creating a tetracyclic pyrene-shaped system. The phenyl ring forms an intermolecular stack with the benzoquinone ring, as a result of aromatic pi-pi interactions.
authors.affiliation: Molecular and Structural Biology Division, Central Drug Research Institute, Lucknow 226 001, India.
authors.forename: S
authors.initials: S
authors.lastname: Sarkhel
authors.lastname: Shefali
authors.forename: V T
authors.initials: VT
authors.lastname: Mathad
authors.forename: K
authors.initials: K
authors.lastname: Raj
authors.forename: A P
authors.initials: AP
authors.lastname: Bhaduri
authors.forename: P R
authors.initials: PR
authors.lastname: Maulik
authors.forename: C K
authors.initials: CK
authors.lastname: Broder
authors.forename: J A
authors.initials: JA
authors.lastname: Howard
mesh_terms: D002934:Cinnamates / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009285:Naphthoquinones; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry
chemical_list: C441506:1-(5,8-dihydro-1,4-dihydroxy-5,8-dioxo-2-naphthyl)-4-methylpent-3-en-1-yl cinnamate; D002934:Cinnamates; D009285:Naphthoquinones