title: Structure-molluscicidal activity relationships of acylphloroglucinols from ferns.
abstract: The molluscicidal activity of 12 phloroglucinol derivatives previously isolated from Elaphoglossum piloselloides, E. gayanum, E. yungense, and E. lindbergii, as well as 3 known acylphloroglucinols, now reported from an Argentine collection of Dryopteris wallichiana, was evaluated against the schistosomiasis vector snail Biomphalaria peregrina. Molluscicidal effects were analyzed and compared with those previously observed for 4 acylphloroglucinols from E. piloselloides and their corresponding peracetylated derivatives, in order to draw structure-activity relationships. The most active compounds were the prenylated desaspidins elaphogayanin B and elaphopilosins A and B (LD50 = 1.90, 2.90, and 0.94 ppm, respectively), together with the only evaluated prenylated para-aspidin, elaphopilosin C (LD50 = 2.15 ppm). Quantitative structure-activity relationships (QSAR) were studied by means of a semiempirical method (PM3) for the 24 natural phloroglucinol derivatives included in this paper. The descriptor molecular volume was found to have good correlation with the observed molluscicidal activity (r2 = 0.77). The derived equation can be considered useful to predict the molluscicidal activity of bi and tricyclic acylphloroglucinols. The QSAR analysis showed that there is an optimum volume for high activity, probably related to the size of a receptor's active site. Bigger molecules display lower activity.
authors.affiliation: INQUINOA - CONICET, Ayacucho 471, San Miguel de Tucumán, Tucumán 4000, Argentina. csocolsky@gmail.com
authors.forename: Cecilia
authors.initials: C
authors.lastname: Socolsky
authors.forename: Susana
authors.initials: S
authors.lastname: Borkosky
authors.forename: Alicia
authors.initials: A
authors.lastname: Bardón
mesh_terms: D000818:Animals; D001118:Argentina; D001688:Biological Products; D002850:Chromatography, Gel; D002855:Chromatography, Thin Layer; D029624:Ferns / Q000737:chemistry*; D007928:Lethal Dose 50; D009682:Magnetic Resonance Spectroscopy; D008975:Molluscacides; D010696:Phloroglucinol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000633:toxicity*; D021281:Quantitative Structure-Activity Relationship; D027343:Rhizome / Q000737:chemistry; D012908:Snails; D013329:Structure-Activity Relationship
chemical_list: D001688:Biological Products; D008975:Molluscacides; D010696:Phloroglucinol