A novel antibacterial iridoid and triterpene from Caiophora coronata.
Bioassay-guided fractionation of the antibacterial CH(2)Cl(2)-MeOH extract obtained from the aerial parts of the Argentinean plant Caiophora coronata led to the isolation of a new triterpene, 1beta,3beta-dihydroxyurs-12-en-27-oic acid, 1, and a new iridoid, 1alpha-methoxy-6alpha,10-dihydroxyisoepiiridomyrmecin (caiophoraenin), 2, along with the known iridoid isoboonein 3. Their structures were established by spectroscopic techniques (1D and 2D NMR, HRFABMS, FTIR). The MIC values of isolated compounds were determined against methicillin-sensitive (MSSA) and -resistant (MRSA) strains of Staphylococcus aureus, Bacillus subtilis (BS), vancomycin-resistant Enterococcus faecium (VREF), Escherichia coli (EC), E. coli imp (ECimp), and Candida albicans (CA). Compound 1 was found active against BS, MSSA, MRSA, VREF, and ECimp with MIC values of 2, 4, 4, 4, and 16 microg/mL, respectively.
Khera
Smriti
S
Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 E Mabel Street, Tucson, Arizona 85721, USA.
Woldemichael
Girma M
GM
Singh
Maya P
MP
Suarez
Enrique
E
Timmermann
Barbara N
BN
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001118:Argentina; D001412:Bacillus subtilis / Q000187:drug effects; D016984:Enterococcus faecium / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D039823:Iridoids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
C482834:1beta,3beta-dihydroxyurs-12-en-27-oic acid; D000900:Anti-Bacterial Agents; D039823:Iridoids; D014315:Triterpenes; C482835:caiophoraenin