title: Isolation of natural compounds from Phlomis stewartii showing α-glucosidase inhibitory activity.
abstract: Stewartiiside (1), a phenylethanoid glycoside and three 28-nortriterpenoids: stewertiisins A-C [(17R)-19(18→17)-abeo-3α,18β,23,24-tetrahydroxy-28-norolean-12-ene, 2; (17R)-19(18→17)-abeo-2α,16β,18β,23,24-pentahydroxy-28-norolean-12-en-3-one, 3; (17R)-19(18→17)-abeo-2α,3α,23,24-tetrahydroxy-28-noroleane-11,13-diene, 4] together with eight known compounds: lunariifolioside (5), notohamosin A (6), phlomispentanol (7), isorhamnetin 3-(6-p-coumaroyl)-β-D-glucopyranoside (8), tiliroside (9), caffeic acid (10), p-hydrxybenzoic acid (11) and oleanolic acid (12) were isolated from the ethyl acetate soluble fraction of the methanolic extract of whole plant of Phlomis stewartii. The structures of these isolates (1-12) were elucidated by the combination of 1D ((1)H and (13)C NMR), 2D (HMQC, HMBC COSY, NOESY) NMR spectroscopy and mass spectrometry (EIMS, HREIMS, FABMS, HRFABMS) and in comparison with literature data of related compounds. All the isolates (1-12) showed α-glucosidase inhibitory activity with IC50 values ranging between 14.5 and 355.4 μM, whereas, compounds 1, 5, 9 and 10 showed promising α-glucosidase inhibitory activity with IC50 values below 30 μM.
authors.affiliation: Department of Chemistry, Baghdad-ul-Jadeed Campus, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
authors.forename: Bushra
authors.initials: B
authors.lastname: Jabeen
authors.forename: Naheed
authors.initials: N
authors.lastname: Riaz
authors.forename: Muhammad
authors.initials: M
authors.lastname: Saleem
authors.forename: Muhammad Akram
authors.initials: MA
authors.lastname: Naveed
authors.forename: Muhammad
authors.initials: M
authors.lastname: Ashraf
authors.forename: Umber
authors.initials: U
authors.lastname: Alam
authors.forename: Hafiza Mehwish
authors.initials: HM
authors.lastname: Rafiq
authors.forename: Rasool Bakhsh
authors.initials: RB
authors.lastname: Tareen
authors.forename: Abdul
authors.initials: A
authors.lastname: Jabbar
mesh_terms: D002109:Caffeic Acids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D002396:Catechols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010154:Pakistan; D010616:Phenanthrenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D031345:Phlomis / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: C494157:2-(3,4-dihydroxyphenyl)ethylO-beta-apiofuranosyl-(1-6)-O-(O-beta-apiofuranosyl-(1-4)-alpha-rhamnopyranosyl-(1-3))-4-O-(E)-caffeoyl-beta-glucopyranoside; D002109:Caffeic Acids; D002396:Catechols; D065089:Glycoside Hydrolase Inhibitors; D006027:Glycosides; D010616:Phenanthrenes; C000589149:stewartiiside; C040048:caffeic acid
keywords: 28-Nortriterpenoids; Phenylethanosids; Phlomis stewartii; α-Glucosidase inhibition