title: Geranins A and B, new antiprotozoal A-type proanthocyanidins from Geranium niveum.
abstract: Bioassay-guided fractionation of the antiprotozoal extract of Geranium niveum led to the isolation of two new A-type proanthocyanidins, epi-afzelechin-(4beta-->8, 2beta-->O-->7)-afzelechin (1) and epi-catechin-(4beta-->8, 2beta-->O-->7)-afzelechin (2). Compounds 1 and 2 were given the trivial names of geranins A and B, respectively. In addition, five known compounds, mahuannin B (3), reynoutrin (4), hyperin (5), methyl gallate (6), and 3-beta-caffeoyl-12-oleanen-28-oic acid (7), were obtained. The structures of the new proanthocyanidins were elucidated by spectroscopic and chemical methods as well as CD measurements. Compounds 1, 2, and 4-7 were tested against axenically grown trophozoites of Giardia lamblia and Entamoeba histolytica.
authors.affiliation: Facultad de Química, Universidad Nacional Autónoma de México, Coyoacán 04510, México D.F., México.
authors.forename: F
authors.initials: F
authors.lastname: Calzada
authors.forename: C M
authors.initials: CM
authors.lastname: Cerda-García-Rojas
authors.forename: M
authors.initials: M
authors.lastname: Meckes
authors.forename: R
authors.initials: R
authors.lastname: Cedillo-Rivera
authors.forename: R
authors.initials: R
authors.lastname: Bye
authors.forename: R
authors.initials: R
authors.lastname: Mata
mesh_terms: D000818:Animals; D000872:Anthocyanins / Q000302:isolation & purification / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification / Q000494:pharmacology; D000981:Antiprotozoal Agents / Q000302:isolation & purification / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D004748:Entamoeba histolytica / Q000187:drug effects; D016829:Giardia lamblia / Q000187:drug effects; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D019684:Magnoliopsida / Q000737:chemistry*; D008800:Mexico; D008958:Models, Molecular; D008968:Molecular Conformation; D018517:Plant Roots / Q000737:chemistry; D044945:Proanthocyanidins; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014407:Tumor Cells, Cultured
chemical_list: D000872:Anthocyanins; D000972:Antineoplastic Agents, Phytogenic; D000981:Antiprotozoal Agents; D044945:Proanthocyanidins; C120205:geranin A; C120206:geranin B