title: Pregnane steroidal glycosides and their cytostatic activities.
abstract: Four new steroidal glycosides such as 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1 → 4)-β-D-oleandropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside-12-β-tigloyl-14-β-hydroxy-17-β-pregnane (1), 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1 → 4)-β-D-oleandropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside-12-β-(2'-amino)-benzoyl-14-β-hydroxy-17-β-pregnane (2), 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1 → 4)-β-D-oleandropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside-12-β-14-β-dihydroxy-17-α-pregnane (3) and 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1 → 4)-β-D-oleandropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside-12-β-14-β-dihydroxy-17-β-pregnane (4) were isolated from the aerial parts of Ceropegia fusca Bolle (Asclepiadaceae), a crassulacean acid metabolism plant, an endemic species to the Canary Islands that has been used in traditional medicine as a cicatrizant, vulnerary and disinfectant. The dichloromethane extract exhibited significant cytostatic activity against HL-60, A-431 and SK-MEL-1 cells, human leukemic, epidermoid carcinoma and melanoma cells, respectively. As shown in Table I, compounds 1 and 2 showed very similar IC(50) values. The acetylation of 1 to give the diacetate 5 increases 5-fold the cytotoxicity against HL-60 cells. Compounds 3 and 4 did not show cytotoxicity at the assayed concentrations. With respect to the compounds containing only the steroid ring (6-8), the presence of a charged O-amino-benzoyl but not a tigloyl group improved the cytotoxicity.
authors.affiliation: Departamento de Química de Productos Naturales y Biotecnología, Instituto de Productos Naturales y Agrobiología de Canarias, La Laguna, Tenerife, Canary Islands. vpergarw@gobiernodecanarias.org
authors.forename: Víctor P
authors.initials: VP
authors.lastname: García
authors.forename: Jaime
authors.initials: J
authors.lastname: Bermejo
authors.forename: Sara
authors.initials: S
authors.lastname: Rubio
authors.forename: José
authors.initials: J
authors.lastname: Quintana
authors.forename: Francisco
authors.initials: F
authors.lastname: Estévez
mesh_terms: D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D054697:Cytostatic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D030012:Gentiana / Q000737:chemistry / Q000378:metabolism; D006027:Glycosides / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D035261:Plant Components, Aerial / Q000737:chemistry / Q000378:metabolism; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D011278:Pregnanes / Q000302:isolation & purification / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D000970:Antineoplastic Agents; D054697:Cytostatic Agents; D006027:Glycosides; D010936:Plant Extracts; D011278:Pregnanes