title: A new antibacterial benzophenone glycoside from Psidium guajava (Linn.) leaves.
abstract: Bioactivity-guided fractionation of methanol extract from the leaves of Psidium guajava L. (Myrtaceae) yielded a new benzophenone glycoside, Guajaphenone A (2) together with two known compounds, Garcimangosone D (1) and Guaijaverin (3). Their structures were elucidated by analysis of spectroscopic data including 1D and 2D NMR and electrospray ionisation mass spectrometry (ESI-MS). The isolated compounds were screened against standard strains of Gram-positive and Gram-negative bacteria using broth dilution assay method, and the MIC values determined and compared with reference antibiotic ceftriaxone. They were found to have significant antibacterial activities against Escherichia coli and Staphylococcus aureus with all of them showing better activities against S. aureus, but displaying weaker activities, in comparison to ceftriaxone. However, despite reduced effect of these compounds against the organisms, this work opens the perspective to use these molecules as 'leads' for the design of novel and selective drug candidates for some tropical infectious diseases.
authors: a Department of Pharmaceutical and Medicinal Chemistry , Faculty of Pharmaceutical Sciences, University of Port Harcourt , Port Harcourt , Nigeria.
authors: Stanley E
authors: SE
authors: Ukwueze
authors: Patience O
authors: PO
authors: Osadebe
authors: Festus B C
authors: FB
authors: Okoye
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification; D001577:Benzophenones / Q000737:chemistry* / Q000302:isolation & purification; D004926:Escherichia coli / Q000187:drug effects; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D031647:Psidium / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D001577:Benzophenones; D006027:Glycosides; D010936:Plant Extracts; C000602383:guajaphenone A
keywords: Guajaphenone A; Psidium guajava; antibacterial; benzophenone glycoside; ceftriaxone