title: Agapanthussaponins A-D, new potent cAMP phosphodiesterase inhibitors from the underground parts of Agapanthus inapertus.
abstract: The saponin fraction prepared from the methanolic extract of the underground parts of Agapanthus inapertus was found to exhibit inhibitory activity on cAMP phosphodiesterase (55.2%) at a concentration of 100 micrograms/ml. From this fraction, four new steroidal saponins, designated as agapanthussaponin A (1), B (2), C (3) and D (4), were isolated as the active principles, along with an inactive new furostanol saponin (5). The structures of 1-5 were determined by spectroscopic data and hydrolysis. The IC50 of 1-4 on cAMP phosphodiesterase were 0.7, 1.2, 1.1 and 2.0 (x 10(-5) M), respectively, which are more potent than that of papaverine (IC50 3.0 x 10(-5) M).
authors.affiliation: Tokyo College of Pharmacy, Japan.
authors.forename: O
authors.initials: O
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Mimaki
authors.forename: Y
authors.initials: Y
authors.lastname: Sashida
authors.forename: T
authors.initials: T
authors.lastname: Nikaido
authors.forename: T
authors.initials: T
authors.lastname: Ohmoto
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors*; D002240:Carbohydrate Sequence; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D010840:Phytosterols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010944:Plants / Q000737:chemistry*; D012503:Saponins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D010840:Phytosterols; D012503:Saponins; D015105:3',5'-Cyclic-AMP Phosphodiesterases