title: Chemical transformation of terpenoids. X. Ionophoretic activities of macrocyclic lactone epoxides synthesized from geraniol.
abstract: Two coronand-type 18-membered lactone epoxides, i.e., geranyl dimeric lactone diepoxide (GL2E2, 10) and tetraepoxide (GL2E4, 11), were synthesized from geraniol as diastereomeric mixtures. Among them, GL2E4 (11) was shown to exhibit ion-transport activity for Ca2+ ion in the test using a W-07 (liquid-membrane type) apparatus and ion-permeation activities for Ca2+ and K+ ions across the human erythrocyte membrane. Isolation of six component diastereomers of GL2E4 (11) [GL2E4-1 (11c), -2 (11d), -3 (11e), -4 (11f), -5 (11g), -6 (11h)], was effected by HPLC separation of two diastereomeric tetraepoxides (11a, 11b) which were prepared from two diepoxides (GL2E2-1, 10a and GL2E2-2, 10b). The relative stereostructures of these diastereomers were determined by a combination of X-ray diffraction and 1H-NMR analyses. Among the six diastereomers, S2-symmetrical GL2E4-4 (11f) exhibited the strongest ion-transport activity for Ca2+ ion while C2-symmetrical GL2E4-6 (11h) exhibited the strongest ion-permeation activity for Ca2+ ion across the human erythrocyte membrane.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Hiroshima, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shibuya
authors.forename: K
authors.initials: K
authors.lastname: Ohashi
authors.forename: N
authors.initials: N
authors.lastname: Narita
authors.forename: T
authors.initials: T
authors.lastname: Ishida
authors.forename: I
authors.initials: I
authors.lastname: Kitagawa
mesh_terms: D000080462:Acyclic Monoterpenes; D004852:Epoxy Compounds / Q000138:chemical synthesis* / Q000494:pharmacology; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007476:Ionophores / Q000138:chemical synthesis* / Q000494:pharmacology; D007783:Lactones / Q000138:chemical synthesis* / Q000494:pharmacology; D013729:Terpenes / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000080462:Acyclic Monoterpenes; D004852:Epoxy Compounds; D007476:Ionophores; D007783:Lactones; D013729:Terpenes; C007836:geraniol