title: Cyclopeptide alkaloids from Scutia buxifolia Reiss.
abstract: Scutianene E (1), 3,4,28-tris-epi-scutiaene E (2), 28-epi-scutianene E (3) and scutianene L (4), four neutral cyclopeptide alkaloids, were isolated from Scutia buxifolia Reiss, together with four known cyclopeptide alkaloids, scutianines B, C, D and E. Scutianenes 1-3 are diastereoisomeric compounds, with 3-hydroxyleucine as a β-hydroxy amino acid unit, which is connected to the styryl fragment via an ether bridge, β-phenylserine, as a common ring-bonded amino acid residue. Attached to the amino group of β-hydroxyamino acid is a side chain [trans-CH=CH-Ph]. The structures of the peptides were elucidated by means of spectroscopic analysis, including extensive 2D NMR studies. The stereochemistry for the diastereomeric 3,4,28-tris-epi-scutiaene E and 28-epi-scutianene E was confirmed by X-ray diffraction analysis of their O-acetyl derivatives.
authors.affiliation: Departamento de Química (NPPN), Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Graciela
authors.initials: G
authors.lastname: Maldaner
authors.forename: Patricia
authors.initials: P
authors.lastname: Marangon
authors.forename: Vinicius
authors.initials: V
authors.lastname: Ilha
authors.forename: Miguel S Balparda
authors.initials: MS
authors.lastname: Caro
authors.forename: Robert A
authors.initials: RA
authors.lastname: Burrow
authors.forename: Ionara Irion
authors.initials: II
authors.lastname: Dalcol
authors.forename: Ademir F
authors.initials: AF
authors.lastname: Morel
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification*; D018360:Crystallography, X-Ray; D008968:Molecular Conformation; D015394:Molecular Structure; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification*; D027823:Rhamnaceae / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D010456:Peptides, Cyclic; C432973:scutianine C