title: Flemingins G-O, cytotoxic and antioxidant constituents of the leaves of Flemingia grahamiana.
abstract: The known flemingins A-C (1-3) and nine new chalcones, named flemingins G-O (4-12), along with deoxyhomoflemingin (13) and emodin (14) were isolated from a leaf extract of Flemingia grahamiana. The isolated chalcones were found to have a geranyl substituent modified into a chromene ring possessing a residual chain, as shown by spectroscopic methods. The leaf extract showed an IC50 value of 5.9 μg/mL in a DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay. The chalcones flemingins A, B, C, G, and H were active in the DPPH radical scavenging assay (ED50 4.4-8.9 μM), while flemingins A and C showed cytotoxicity against MCF-7 human breast cancer cells (IC50 8.9 and 7.6 μM, respectively).
authors.affiliation: Department of Chemistry, University of Nairobi , POB 30197-00100, Nairobi, Kenya.
authors.forename: Ivan
authors.initials: I
authors.lastname: Gumula
authors.forename: John Patrick
authors.initials: JP
authors.lastname: Alao
authors.forename: Isaiah Omolo
authors.initials: IO
authors.lastname: Ndiege
authors.forename: Per
authors.initials: P
authors.lastname: Sunnerhagen
authors.forename: Abiy
authors.initials: A
authors.lastname: Yenesew
authors.forename: Máté
authors.initials: M
authors.lastname: Erdélyi
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001713:Biphenyl Compounds; D047188:Chalcones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D007887:Fabaceae / Q000737:chemistry*; D005260:Female; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006801:Humans; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry; D010851:Picrates; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D001713:Biphenyl Compounds; D047188:Chalcones; D016166:Free Radical Scavengers; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; C000594570:flemingin G; C000594571:flemingin H; C004931:1,1-diphenyl-2-picrylhydrazyl