title: Complete 1H and 13C NMR assignments for two new monodesmoside saponins from Pentaclethra macroloba (Willd.) Kuntze.
abstract: A detailed NMR study and full assignments of the 1H and 13C spectral data for two novel triterpenoid saponins isolated from the stem bark of Pentaclethra macroloba (Willd.) Kuntze are described. Their structures were established using a combination of 1D and 2D NMR techniques including 1H,1H-COSY, TOCSY, NOESY, gs-HMQC and gs-HMBC, and also electrospray ionization mass spectrometry and chemical methods. The structures were established as 3beta-O-([O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-[O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)])-alpha-L-arabinopyranosylhederagenin (1) and 3beta-O-)[O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-[O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)])-alpha-L-arabinopyranosyloleanolic acid (2).
authors.affiliation: Universidade do Estado do Rio Grande do Norte, Mossoró, RN 59610-210, Brazil.
authors.forename: Francisco Arnaldo
authors.initials: FA
authors.lastname: Viana
authors.forename: Yvone Brígido M
authors.initials: YB
authors.lastname: Pouliquen
authors.forename: Manoel
authors.initials: M
authors.lastname: Andrade-Neto
authors.forename: Gilvandete Maria P
authors.initials: GM
authors.lastname: Santiago
authors.forename: Otília Deusdênia L
authors.initials: OD
authors.lastname: Pessoa
authors.forename: Edson
authors.initials: E
authors.lastname: Rodrigues-Filho
authors.forename: Raimundo
authors.initials: R
authors.lastname: Braz-Filho
mesh_terms: D002240:Carbohydrate Sequence; D002247:Carbon Isotopes; D007887:Fabaceae / Q000737:chemistry*; D006859:Hydrogen; D008969:Molecular Sequence Data; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D024301:Plant Bark / Q000737:chemistry; D012502:Sapogenins / Q000737:chemistry / Q000302:isolation & purification; D012503:Saponins / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: C498379:3-O-((O-glucopyranosyl--1-2-O-glucopyranosyl-1-4-glucopyranosyl-1-3-O-rhamnopyranosyl-1-2)(O-glucopyranosyl-1-3-O-glucopyranosyl-1-4))arabinopyranosyloleanolic acid; C498376:3-O-((O-glucopyranosyl-1-2-O-glucopyranosyl-1-4-glucopyranosyl-1-3-O-rhamnopyranosyl-1-2)(O-glucopyranosyl-1-3-O-glucopyranosyl-1-4))arabinopyranosylhederagenin; D002247:Carbon Isotopes; D012502:Sapogenins; D012503:Saponins; D006859:Hydrogen