title: Luteolin, a compound with adenosine A(1) receptor-binding activity, and chromone and dihydronaphthalenone constituents from Senna siamea.
abstract: Activity-guided fractionation led to the isolation of luteolin (1) from the leaves of Senna siamea (syn. Cassia siamea). This compound was found to be an antagonist at the adenosine A(1) receptor with a K(i) value in the low micromolar range. Four additional nonactive compounds (2-5) were also isolated, and their structures were elucidated. One compound was identified as cassia chromone (5-acetonyl-7-hydroxy-2-methylchromone) (2). Three other compounds are new, and they were identified as 5-acetonyl-7-hydroxy-2-hydroxymethyl-chromone (3), 4-(trans)-acetyl-3,6,8-trihydroxy-3-methyldihydronaphthalenone (4), and 4-(cis)-acetyl-3,6,8-trihydroxy-3-methyldihydronaphthalenone (5).
authors.affiliation: Division of Pharmacognosy and Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA, Leiden, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Ingkaninan
authors.forename: A P
authors.initials: AP
authors.lastname: IJzerman
authors.forename: R
authors.initials: R
authors.lastname: Verpoorte
mesh_terms: D002867:Chromones / Q000737:chemistry / Q000302:isolation & purification*; D005419:Flavonoids / Q000378:metabolism*; D047311:Luteolin; D009281:Naphthalenes / Q000737:chemistry / Q000302:isolation & purification*; D010946:Plants, Medicinal / Q000737:chemistry*; D018047:Receptors, Purinergic P1 / Q000378:metabolism*; D013057:Spectrum Analysis
chemical_list: D002867:Chromones; D005419:Flavonoids; D009281:Naphthalenes; D018047:Receptors, Purinergic P1; D047311:Luteolin