title: Sulfated pregnane glycosides from Periploca graeca.
abstract: Six new pregnane glycosides, four of them sulfated derivatives, were isolated from small branches of Periploca graeca. The compounds were identified as 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-en-20-ol-3beta-yl O-(2-O-acetyl-beta-D-digitalopyranosyl)-(1-->4)-beta-D-cymaropyranoside (1), 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-en-20-ol-3beta-yl O-beta-D-oleandropyranosyl-(1-->4)-beta-D-oleandropyranoside (2), 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-en-20-ol-3beta-yl O-beta-D-oleandropyranoside (3), 16alpha-[(6-O-sulfo-beta-D-glucopyranosyl)oxy]pregn-5-ene-3beta,20-diol (4), 20-O-[(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl-(1-->2)-beta-D-digitalopyranosyl)oxy]pregn-5-en-16beta-ol-3beta-yl O-beta-D-digitalopyranosyl-(1-->4)-beta-d-cymaropyranoside (5), and calogenin 3-O-beta-D-digitalopyranoside-20-O-beta-D-canaropyranoside (6). Three pregnane glycosides, previously reported from the genus Periploca, were also isolated. Structures were established on the basis of spectroscopic analyses, including 1D and 2D NMR experiments, HRESIMS, elemental analysis, and chemical degradation.
authors.affiliation: Dipartimento di Chimica Bioorganica e Biofarmacia, Università di Pisa, Via Bonanno 33, 56126 Pisa, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Siciliano
authors.forename: Ammar
authors.initials: A
authors.lastname: Bader
authors.forename: Nunziatina
authors.initials: N
authors.lastname: De Tommasi
authors.forename: Ivano
authors.initials: I
authors.lastname: Morelli
authors.forename: Alessandra
authors.initials: A
authors.lastname: Braca
mesh_terms: D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification*; D007558:Italy; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D031109:Periploca / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D011278:Pregnanes / Q000737:chemistry* / Q000302:isolation & purification*; D013431:Sulfates / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D006027:Glycosides; D011278:Pregnanes; D013431:Sulfates