ABSTRACT
Two new pyrroloiminoquinone alkaloids of the discorhabdin class, along with 12 compounds including one previously described synthetic derivative of the same and related skeletal classes, were isolated from the sponge Sceptrella sp., collected from Gageodo, Korea. The structures of these new compounds, designated as (-)-3-dihydrodiscorhabdin D (11) and (-)-discorhabdin Z (12), were determined by combined spectroscopic analyses. Compound 12 possesses an unusual hemiaminal group among the discorhabdin alkaloids. These compounds exhibited moderate to significant cytotoxicity, antibacterial activity, and inhibitory activity against sortase A.
Subject(s)
Alkaloids/isolation & purification , Alkaloids/pharmacology , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Heterocyclic Compounds, 4 or More Rings/isolation & purification , Heterocyclic Compounds, 4 or More Rings/pharmacology , Porifera/chemistry , Quinones/isolation & purification , Quinones/pharmacology , Alkaloids/chemistry , Aminoacyltransferases/antagonists & inhibitors , Animals , Anti-Bacterial Agents/chemistry , Antineoplastic Agents/chemistry , Bacillus subtilis/drug effects , Bacterial Proteins/antagonists & inhibitors , Cysteine Endopeptidases , Drug Screening Assays, Antitumor , Escherichia coli/drug effects , Heterocyclic Compounds, 4 or More Rings/chemistry , Humans , K562 Cells , Marine Biology , Micrococcus luteus/drug effects , Nuclear Magnetic Resonance, Biomolecular , Proteus vulgaris/drug effects , Quinones/chemistry , Salmonella typhimurium/drug effects , Staphylococcus aureus/drug effects , StereoisomerismABSTRACT
Five new dihydroxystyrene metabolites and six known compounds of the same structural class were isolated from an association of the sponges Poecillatra wondoensis and Jaspis sp., collected from Keomun Island, Korea. The structures of novel compounds were determined to be the sodium or N, N-dimethyl guanidinium salts of a dihydroxystyrene dimer (5) and two trimers (6, 7). Two dimers (10, 11) containing imidazole moieties were also identified on the basis of the results of combined spectroscopic analyses. Several compounds exhibited weak to moderate inhibitory effects against isocitrate lyase and sortase A enzymes derived from microorganisms.
Subject(s)
Aminoacyltransferases/antagonists & inhibitors , Bacterial Proteins/antagonists & inhibitors , Enzyme Inhibitors/isolation & purification , Isocitrate Lyase/antagonists & inhibitors , Porifera/chemistry , Styrenes/isolation & purification , Animals , Cysteine Endopeptidases , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Humans , Korea , Microbial Sensitivity Tests , Molecular Structure , Styrenes/chemistry , Styrenes/pharmacologyABSTRACT
Four sesquiterpene glucosides were isolated from Ixeris sonchifolia Hance. The structure of a new compound (1) was assigned as 9beta-monohydroxy-2,12-dioxo-guaia-3,11(13)-dien-1alpha,5alpha,6beta,7alpha,9beta,10alphaH-12,6-olide-9-O-beta-D- glucopyranoside (ixerinoside). In addition, unambiguous and complete assignments of (1)H NMR chemical shifts for crepidiaside A (2), ixerin Z (3), and 11,13alpha-dihydroixerin Z (4) are presented. The assignments were achieved by two-dimensional NMR (gCOSY, gHSQC, gHMBC, NOESY) and one-dimensional nuclear Overhauser effect (NOE) experiments.