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Abstract: The ethanol extract and its solvent subfractions, partitioned by n-hexane (HX), chloroform (CF) and ethylacetate (EA), from Enteromorpha prolifera were measured for antioxidant activities, and a structural identification of the active compound was performed using spectroscopic techniques. The CF fraction showed the most potent 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl (OH) radical scavenging activities with strong reducing ability. The DPPH and hydroxyl radical scavenging capacities of the CF fraction were comparable to the capacities of the positive controls, BHA and α-tocopherol, at concentrations ranging from 0.25 to 1.0mg/mL. However, little correlation (r 2 =0.03–0.48) was observed between antioxidant activities and total phenolic contents of the extracts. Further fractionation and spectroscopic analysis of the CF fraction suggested that the strong antioxidant activity of the extracts from E. prolifera was because of a chlorophyll compound, pheophorbide a, rather than phenolic compounds. [Copyright &y& Elsevier]

Abstract: Two sesterterpene sulfates (1–2) were isolated from tropical sponge Hippospongia sp. and their inhibitory activities against isocitrate lyase (ICL) from the rice blast fungus Mgnaporthe grisea were evaluated. Compound 3 was obtained by hydrolysis of compound 1. Compounds 1 and 3 were found to be potent ICL inhibitors, which inhibited appressorium formation and C2 carbon utilization in M. grisea. Our results suggest that ICL plays crucial role in appressorium formation of M. grisea and is a new target for the protection of rice blast disease. [Copyright &y& Elsevier]

Psammaplin A (PsA) is a phenolic natural product isolated from a marine sponge, which showed a potent cytotoxicity against several cancer cell lines. In present study, PsA was found to inhibit mammalian aminopeptidase N (APN) that plays a key role in tumor cell invasion and angiogenesis. PsA inhibited the APN activity with an IC50 of 18 μM in a non-competitive manner. Moreover, PsA potently inhibited the proliferation of several cancer and endothelial cells. Interestingly, the anti-proliferative effect of PsA was dependent on the cellular amount of APN expression. Finally, PsA suppressed the invasion and tube formation of endothelial cells stimulated by basic fibroblast growth factor. These data demonstrate that PsA is a new inhibitor of APN and can be developed as a novel anti-angiogenic agent. [Copyright &y& Elsevier]

Gagunins A–G, seven new diterpenoids were isolated from the sponge Phorbas sp. collected from Gagu-Do, Korea. The carbon skeleton of these highly oxygenated metabolites was determined to be an unusual 10,13-bis-epi-homoverrucosane on the basis of combined chemical and spectral methods. Stereochemical assignments of these diterpenoids were accomplished by extensive ROESY and 1D NOESY experiments. The novel compounds exhibited significant cytotoxicity with values ranging from 0.03 to 51 μg/mL, toward a human leukemia cell-line (K-562). [Copyright &y& Elsevier]

Background and Purpose: Mitochondrial dysfunction contributes to the pathogenesis and maintenance of chemotherapy‐induced peripheral neuropathy (CIPN), a significant limitation of cancer chemotherapy. Recently, the stimulation of mitophagy, a pivotal process for mitochondrial homeostasis, has emerged as a promising treatment strategy for neurodegenerative diseases, but its therapeutic effect on CIPN has not been explored. Here, we assessed the mitophagy‐inducing activity of 3,5‐dibromo‐2‐(2′,4′‐dibromophenoxy)‐phenol (PDE701), a diphenyl ether derivative isolated from the marine sponge Dysidea sp., and investigated its therapeutic effect on a CIPN model. Experimental Approach: Mitophagy activity was determined by a previously established mitophagy assay using mitochondrial Keima (mt‐Keima). Mitophagy induction was further verified by western blotting, immunofluorescence, and electron microscopy. Mitochondrial dysfunction was analysed by measuring mitochondrial superoxide levels in SH‐SY5Y cells and Drosophila larvae. A thermal nociception assay was used to evaluate the therapeutic effect of PDE701 on the paclitaxel‐induced thermal hyperalgesia phenotype in Drosophila larvae. Key Results: PDE701 specifically induced mitophagy but was not toxic to mitochondria. PDE701 ameliorated paclitaxel‐induced mitochondrial dysfunction in both SH‐SY5Y cells and Drosophila larvae. Importantly, PDE701 also significantly ameliorated paclitaxel‐induced thermal hyperalgesia in Drosophila larvae. Knockdown of ATG5 or ATG7 abolished the effect of PDE701 on thermal hyperalgesia, suggesting that PDE701 exerts its therapeutic effect through mitophagy induction. Conclusion and Implications: This study identified PDE701 as a novel mitophagy inducer and a potential therapeutic compound for CIPN. Our results suggest that mitophagy stimulation is a promising strategy for the treatment of CIPN and that marine organisms are a potential source of mitophagy‐inducing compounds. [ABSTRACT FROM AUTHOR]

Abstract: Chemical investigations of the tropical marine sponge Hyrtios sp. have resulted in the isolation of a new alkaloid, 1-carboxy-6-hydroxy-3,4-dihydro-β-carboline (1) together with the known metabolites, 6-hydroxy-3,4-dihydro-1-oxo-β-carboline (2), 5-hydroxy-1H-indole-3-carboxylic acid methyl ester (3), serotonin (4), hyrtiosin A (5), 5-hydroxyindole-3-carbaldehyde (6), and hyrtiosin B (7). Their structures were elucidated on the basis of mass spectrometry and detailed 2D NMR spectroscopic data. Hyrtiosin B (7) displayed a potent inhibitory activity against isocitrate lyase (ICL) of Candida albicans with an IC50 value of 89.0μM. [Copyright &y& Elsevier]

isolation and structure elucidation of three new polyprenyl chromenes (I) [ABSTRACT FROM AUTHOR]

The new polyketides lopouzanones A and B, as well as the new 1-O-acetyl and 2-O-acetyl derivatives of dendrodochol B, were isolated from the sponge-derived marine fungus Lopadostoma pouzarii strain 168CLC-57.3. Moreover, six known polyketides, gliorosein, balticolid, dendrodolide G, dihydroisocoumarine, (–)-5-methylmellein, and dendrodochol B, were identified. The structures of the isolated compounds were determined by a combination of NMR and ESIMS techniques. The absolute configurations of the lopouzanones A and B were determined using the Mosher's method. The cytotoxicity of the isolated compounds against human prostate cancer cells PC-3 and normal rat cardiomyocytes H9c2 was investigated. Gliorosein showed weak DPPH radical-scavenging activity and in vitro cardioprotective effects toward rotenone toxicity and CoCl2-mimic hypoxia. [ABSTRACT FROM AUTHOR]

The motility of zoospores is critical in the disease cycles of the peronosporomycetes that cause devastating diseases in plants, fishes, vertebrates, and microbes. In the course of screening for secondary metabolites regulating the motility of zoospores of Phytophthora capsici , we discovered two new inhibitors from the ethyl acetate extract of the fermentation broth of a marine-derived strain Bacillus sp. 109GGC020. The structures of these novel metabolites were elucidated as new cyclic lipopeptides and named gageopeptins A ( 1 ) and B ( 2 ) by spectroscopic analyses including high resolution MS and extensive 1D and 2D NMR. The stereoconfigurations of 1 and 2 were assigned based on the chemical derivatization studies and reviews of the literature data. Although compounds 1 and 2 impaired the motility of zoospores of P. capsici in dose- and time-dependent manners, compound 1 (IC 50 = 1 μg/ml) was an approximately 400-fold stronger motility inhibitor than 2 (IC 50 = 400 μg/ml). Interestingly, the zoospores halted by compound 1 were subsequently lysed at higher concentrations (IC 50 = 50 μg/ml). Compounds 1 and 2 were also tested against some bacteria and fungi by broth dilution assay, and exhibited moderate antibacterial and good antifungal activities. [ABSTRACT FROM AUTHOR]

Gageotetrins A–C (1–3),a unique class of linear lipopeptides, consisting of di- and tetrapeptidesand a new fatty acid were isolated from a Marine Bacillussubtilis. The structures of 1–3were assigned by spectroscopic data and their absolute stereochemistrieswere ascertained by chemical derivatization. Compounds 1–3displayed good antimicrobial activities withMIC values of 0.01–0.06 μM. However, these compoundsfailed to register any cytotoxicity (GI50> 30 μg/ml)against human cancer cell lines. [ABSTRACT FROM AUTHOR]

Abstract: Bioactivity-guided isolation for the new/novel metabolites from the EtOAc extract obtained from the culture broth of a marine Bacillus sp. 09ID194 followed by chromatographic fractionations and subsequently HPLC purifications led to the isolation of two known macrolides, macrolactins A (1) and Q (2), together with a new glycosylated marcrolide, macrolactin W (3). The chemical structures of compounds 1–3 were assigned based on extensive MS and NMR spectral data analysis and literature review. Compound 3 showed potent antibacterial activity against both Gram-positive and Gram-negative pathogenic bacteria. [Copyright &y& Elsevier]

Abstract: Streptopyrrolidine, a benzyl pyrrolidine derivative, was isolated as an angiogenesis inhibitor from the fermentation broth of a marine Streptomyces sp. isolated from the deep sea sediment. Its structure was elucidated by extensive 2D NMR and mass spectroscopic analyses. Streptopyrrolidine exhibited significant anti-angiogenesis activity. [Copyright &y& Elsevier]

Fucoidans are an interesting group of bioactive sulfated polysaccharides abundant in brown seaweeds. The current study highlights the enrichment and extraction of fucoidan from Chnoospora minima by means of enzyme-assistant extraction using Celluclast and evaluation of its anti-inflammatory potential through in vitro and in vivo studies. The purified C. minima fucoidan (F2,4) inhibited the nitrous oxide (NO) production (IC 50 = 27.82 ± 0.88 μg/ml) and expression of PGE 2 through the subsequent downregulation of iNOS and COX-2 expression in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophages. F2,4 downregulated TNF-α, IL1-β, and IL-6 in RAW 264.7 macrophages in a dose-dependent manner and suppressed NO and ROS production in LPS stimulated zebrafish embryos while exerting a protective effect against the cell damage caused by LPS. Polysaccharide structural characterization was performed using FTIR, HPAE-PAD analysis of the monosaccharide content and NMR spectroscopy. Current findings confirm the potential anti-inflammatory activity of fucoidan purified from C. minima and elaborate its potential application as a functional ingredient in consumer products. [ABSTRACT FROM AUTHOR]

In this study, we isolated and purified secondary metabolites from an edible brown seaweed, Undariopsis peterseniana, and evaluated their anti-inflammatory effects in vitro and in vivo. Apo-9′-fucoxanthinone (Apo-9′), a main anti-inflammatory compound found in the chloroform fraction of U. peterseniana extracts, was first isolated by one-step centrifugal partition chromatography and identified by nuclear magnetic resonance. Apo-9′ significantly decreased nitric oxide (NO), prostaglandin E, pro-inflammatory proteins (inducible NO synthase [iNOS] and cyclooxygenase [COX-2]), and pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-6, and interleukin-1β) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells without exhibiting any cytotoxicity. In vivo, Apo-9′ protected LPS-stimulated zebrafish embryos against inflammatory stress and suppressed the expression of pro-inflammatory proteins such as COX-2 and iNOS. These findings suggest that U. peterseniana extract and Apo-9′ could be used as an anti-inflammatory agent in health care. [ABSTRACT FROM AUTHOR]

Abstract: Acremolin (1), a novel modified base, was isolated from the culture broth of the marine fungus Acremonium strictum. Based on combined spectroscopic analyses, the structure of this compound was that of a methyl guanine base containing an isoprene unit. In addition, the presence of a 1H-azirine moiety is unprecedented among natural products. This compound exhibited weak cytotoxicity against an A549 cell line. [Copyright &y& Elsevier]

Saxitoxin (STX) is a highly toxic marine neurotoxin produced by phytoplankton and a growing threat to ecosystems worldwide due to the spread of toxic algae. Although STX is an established sodium channel blocker, the overall profile of transcriptional levels in STX-exposed organisms has yet to be described. Here, we describe a toxicity assay and transcriptome analysis of the copepod Tigriopus japonicus exposed to STX. The half-maximal lethal concentration of STX was 12.35 μM, and a rapid mortality slope was evident at concentrations between 12 and 13 μM. STX induced changes in swimming behavior among the copepods after 10 min of exposure. In transcriptome analysis, gene ontology revealed that the genes involved in nervous system and gene expression were highly enriched. In addition, the congenital neurological disorder and nuclear factor erythroid 2-related factor 2–mediated oxidative stress pathways were identified to be the most significant in network analysis and toxicity pathway analysis, respectively. This study provides valuable information about the effects of STX and related transcriptional responses in T. japonicus. [Display omitted] • Saxitoxin exposure induced mortality and behavioral changes in Tigriopus japonicus. • Genes involved in neuron system-related pathways were deregulated. • NRF2-mediated oxidative stress response was predicted as the main toxicity pathway. [ABSTRACT FROM AUTHOR]

Although various anticancer drugs have been developed for the treatment of nonsmall cell lung cancer, chemotherapeutic efficacy is still limited. Natural products such as phytochemicals have been screened as novel alternative materials, but alternative funds such as marine bioresources remain largely untapped. Of these resources, marine sponges have undergone the most scrutiny for their biological activities, including antiinflammatory, antiviral, and anticancer properties. However, the biological mechanisms of the activities of these marine sponges are still unclear. We investigated the anticancer activity of marine sponges collected from Kosrae in Micronesia and examined their mechanisms of action using nonsmall cell lung cancer A549 cells as a model system. Of 20 specimens, the Haliclona sp. (KO1304-328) showed both dose- and time-dependent cytotoxicity. Further, methanol extracts of Haliclona sp. significantly inhibited cell proliferation and cell viability. A549 cells treated with Haliclona sp. demonstrated induced expression of c-Jun N-terminal kinase (JNK), p53, p21, caspase-8, and caspase-3. The percentage of apoptotic cells significantly increased in A549 cultures treated with Haliclona sp. These results indicate that Haliclona sp. induces apoptosis via the JNK-p53 pathway and caspase-8, suggesting that this marine sponge is a good resource for the development of drugs for treatment of nonsmall cell lung cancer. [ABSTRACT FROM AUTHOR]

Gold(I)-catalyzed intramolecular 6- endo- dig cyclization of tert-butyl ynoates afforded α-pyrone cores of violapyrones. Moreover, this reaction was successfully applied to the stereospecific syntheses of (+)- and (-)-violapyrone C, which allowed the absolute configuration of natural (+)-violapyrone C to be assigned by comparison of the optical rotations. This first total synthesis, which proceeded in 22 % yield over 10 steps from ( S)-(-)-2-methylbutanol, features silver(I) oxide promoted monobenzylation of 1,4-butanediol, Wittig olefination, Claisen condensation, Corey-Fuchs reaction, and gold(I)-catalyzed α-pyrone synthesis. [ABSTRACT FROM AUTHOR]

Highlights: [ • ] 5β-hydroxypalisadin B was isolated from red seaweed Laurencia snackeyi. [ • ] In vivo anti-inflammatory activity was evaluated in LPS-induced zebrafish embryo. [ • ] The isolated compound could be considered as an effective anti-inflammatory agent. [•] 5β-hydroxypalisadin B could be further developed as a functional ingredient. [ABSTRACT FROM AUTHOR]

Three new 5-hydroxyindole alkaloids ( 1, 2, 3) along with seven known analogs ( 4, 5, 6, 7, 8, 9, 10) were isolated from a Dokdo marine sponge Scalarispongia sp. The elucidation of the structures of the new compounds by spectroscopic analyses indicated that these compounds were an indole glyoxylate ( 1), a mono-indole analog of hyrtinadine A ( 2), and a symmetrical bis-indole with pyridine linker ( 3). The comparison of IC50 values for obtained compounds against a human leukemia cell line revealed that the bis-indole structure is a requirement for cytotoxicity. [ABSTRACT FROM AUTHOR]

Marine sponges are relatively less explored for their chemical features but highly anticipated resource for bioactive compounds. In this paper we report the screening of marine sponges crude extracts for their potential to bind the adenosine A1 receptor. Many samples showed very promising activity and in order to identify the active components, a metabolomics-chemometrics approach is employed. Nuclear magnetic resonance spectroscopy is used for the metabolic profiling of the marine sponges and partial least squares (PLS) and orthogonal PLS (OPLS) algorithms are used to correlate the metabolomics with bioactivity data. Using several two dimensional-NMR techniques, the resonances responsible for the separation of high activity samples from the medium and low activity samples were identified as associated to metabolites like halisulfate 1, halisulfate 3-5, and suvanine (1-5), all belongs to sesterterpenes class. The reference compounds for these metabolites are also tested for the activity, which endorse the findings of the applied methodology. [ABSTRACT FROM AUTHOR]

Abstract: A new marine guanidine-containing compound, pulchranin A (1) was isolated from the marine sponge Monanchora pulchra. Its structure was elucidated by detailed NMR and MS analyses. The Mosher’s method did not allow determination of the absolute configuration of the carbinol center in 1, but after conversion of 1 into the bis-MTPA esters of 1,3-diol 2, the same method was successfully used to solve the problem. Compound 1 was active as an inhibitor of the TRPV1 receptor with an EC50 value of 41.2μM. [Copyright &y& Elsevier]

The component is inactive against Gram-positive and Gram-negative bacteria, but exhibits weak cytotoxicity against an A54 cell line. [ABSTRACT FROM AUTHOR]

Abstract: Three cDNAs encoding allatostatin-like peptides (two myoinhibitory peptides; Paj-MIPI and Paj-MIPII, and one C-type AST; Paj-ASTC) were identified from Pandalopsis japonica through a combination of bioinformatic analysis and PCR-based gene cloning strategy. Paj-MIPI and Paj-MIPII encoded proteins with 189 and 117 amino acid residues, respectively, and a total of 10 mature peptides are putatively produced from the two MIP cDNAs (seven from Paj-MIPI and three from Paj-MIPII). Among the MIPs from various arthropods, their size and organization varied and it was unable to establish the monophyletic evolutionary relationship, which is mainly due to difference in the number and location of the mature peptide W(X6)W motif of each MIP gene. Based on the sequence similarity of six residues flanked by two conserved tryptophan (W) residues, crustacean MIPs could be further classified into at least four groups. Paj-ASTC cDNA (648bp) encoded a protein with 143 amino acid residues. The prepropeptide of Paj-ASTC showed conserved C-type AST characteristics including a signal sequence, two dibasic cleavage sites, and a mature peptide sequence with two cysteine residues at the 7th and 14th positions, creating a disulfide bridge. Based on the sequence similarity in the mature peptides, the ASTCs in arthropods could be further classified into two subgroups, AVSCF-ASTC and PISCF-ASTC. Phylogenetic and sequence similarity analysis showed that Paj-ASTC belonged to the PISCF-ASTC subgroup. Expression studies revealed that AST-like peptides from P. japonica were mainly expressed in neuronal tissues, and the expression of Paj-ASTC was also detected in the intestine. Eyestalk ablation (ESA) altered the mRNA expression levels of both Paj-MIPs and Paj-ASTC, suggesting that factors from the sinus gland/X organ complex had a transient effect on AST-like peptide transcription. Correlation analysis of three allatostatin-like peptides revealed a strong positive correlation in brain tissues, suggesting that transcriptional regulation of three allatostatin-like peptides from P. japonica is influenced by the similar physiological condition. [Copyright &y& Elsevier]

Abstract: As a part of an ongoing search for novel antioxidants from the salt marsh plants, bioactivity-isolation and structure determination of constituents from Salicornia herbacea were performed. One new triterpenoid saponin (4), along with three known saponins (1–3), has been isolated from n-BuOH fraction of S. herbacea. On the basis of the spectroscopic methods, the structure of the new saponin 4 was elucidated as 3β-hydroxy-23-oxo-30-noroleana-12, 20(29)-diene-28-oic acid 3-O-β-d-glucuronopyranosyl-28-O-β-d-glucopyranoside. Scavenging effects of saponins 1-4 were examined on 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical and peroxynitrite. Particularly, saponin 3 exerted significant antioxidant activity on both authentic peroxynitrite and peroxynitrite generated from morpholinosydnonimine (SIN-1). [Copyright &y& Elsevier]

Abstract: Dibrominated resorcinol dimers were synthesized by reaction of 4-bromoresorcinol with aldehydes under reflux in ethanol in the presence of HCl. Subsequent dehalogenation yielded the corresponding monobrominated compounds and a fully dehalogenated dimer. Of the dimers, 6,6′-((4-hydroxyphenyl)methylene)bis(4-bromobenzene-1,3-diol) (4) displayed potent antibacterial activity and inhibitory activity against isocitrate lyase Candida albicans. [Copyright &y& Elsevier]

Abstract: In this study, the potent anti-tumor effects of brown algae on human leukemia HL-60 cells were investigated. The Sargassum siliquastrum extract among the 14 species of brown algae exhibited profound growth inhibitory effect on HL-60 cells in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, therefore, S. siliquastrum was selected for use in further experiments. The highest inhibitory activity of S. siliquastrum on HL-60 cells was detected in the chloroform fraction, and the active compound was identified as a kind of chromene, sargachromanol E (SE). SE treatment showed significant growth inhibitory effects on HL-60 cells in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies, fragmented DNA ladder, and the accumulation of DNA in the sub-G1 phase of cell cycle. SE induced apoptosis was accompanied by downregulation of Bcl-xL, upregulation of Bax, activation of caspase-3, and cleavage of poly (ADP-ribose) polymerase (PARP). Moreover, z-DEVD-fmk, a caspase-3 inhibitor, significantly inhibited cell cytotoxicity, apoptotic characteristics such as apoptotic bodies, sub-G1 DNA content, and cleavage of PARP induced by SE. These results suggest that SE exerts its growth inhibitory effects on HL-60 cells through caspase-3-mediated induction of apoptosis. Therefore, SE offers promising chemotherapeuric potential to prevent cancers such as human leukemia. [Copyright &y& Elsevier]

Abstract: Guided by the inhibitory activities of indole-containing natural products against isocitrate lyase (ICL) from Candida albicans and sortase A (SrtA) from Staphylococcus aureus, a series of compounds structurally analogous to natural products were synthesized. Eight SrtA inhibitors and an ICL inhibitor having higher activities than the natural products were discovered by screening the enzyme inhibitory activities of synthesized compounds. Among the SrtA inhibitors discovered, six exhibited higher activities than p-hydroxymercuribenzoic acid, which suggests that these compounds have great potential as alternative antibacterial agents. [Copyright &y& Elsevier]

Abstract: A new series of bromophenols was synthesized by reactions of corresponding phenol analogs with bromine. The synthesized compounds were tested for inhibitory activity against isocitrate lyase (ICL) of Candida albicans and antimicrobial activity against Gram-positive and, Gram-negative bacteria and fungi. Among the synthesized bromophenols, bis(3-bromo-4,5-dihydroxyphenyl)methanone (11) and (3-bromo-4,5-dihydroxyphenyl)(2,3-dibromo-4,5-dihydroxyphenyl)methanone (12) displayed potent inhibitory activities against ICL, showing a stronger inhibitory effects than were found with natural bromophenol 1. The preliminary structure–activity relationships were investigated in order to determine the essential structural requirements for the inhibitory activities of these compounds against ICL of C. albicans. [Copyright &y& Elsevier]

Abstract: A series of halophenols was prepared by the reaction of bis(hydroxyphenyl)methanes with effective halogenating agents such as bromine and sulfuryl chloride. One of these compounds, a biologically active halophenol—2,2′,3,3′-tetrabromo-4,4′,5,5′-tetrahydroxydiphenylmethane (1)—frequently isolated from red algae, was synthesized for the first time. Other halophenols included several novel compounds, together with known derivatives that were synthesized from the phenolic intermediates, bis(3,4-dihydroxyphenyl)methane (5) and bis(2-hydroxyphenyl)methane (14). All of the synthesized compounds were tested for antimicrobial activity against Gram-positive, Gram-negative bacteria and fungi. The preliminary structure–activity relationship was investigated in order to determine the essential structural requirements for their antimicrobial activity. Of all these halophenols, 2,2′,3,3′,6-pentabromo-4,4′,5,5′-tetrahydroxydiphenylmethane (8) was found to be the most active against Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, and Trichophyton mentagrophytes while 3,3′,5,5′-tetrachloro-2,2′-dihydroxydiphenylmethane (18) exerted a powerful antibacterial effect against Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Proteus vulgaris, and Salmonella typhimurium. [Copyright &y& Elsevier]

Abstract: Seven sesterterpene sulfates (1–7) were isolated from the tropical sponge Dysidea sp. and their inhibitory activities against isocitrate lyase (ICL) from Candida albicans were evaluated. Among the isolated natural products compound 6 and 7 were found to be strong ICL inhibitors. The isolated compounds (1–7) also showed potent antibacterial effect against Bacillus subtilis and Proteus vulgaris, but did not display antifungal activity. [Copyright &y& Elsevier]

Abstract: A series of bromophenols was obtained by isolation from red alga Odonthalia corymbifera and by reactions of bis(hydroxyphenyl)methanes with bromine. New bromophenols including 3,3′,5,5′-tetrabromo-2,2′,4,4′-tetrahydroxydiphenylmethane (10), a regioisomer of the potent antimicrobial natural product, together with known derivatives were synthesized in high yield. All of the isolated and synthesized compounds were tested for antimicrobial activity against Gram-negative, Gram-positive bacteria and fungi. The preliminary structure–activity relationship, to elucidate the essential structure requirements for antimicrobial activity, has been described. Among the isolated natural products 2,2′,3,3′-tetrabromo-4,4′,5,5′-tetrahydroxydiphenylmethane (4) was found to be the most active derivative against Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, and Trichophyton mentagrophytes. The synthetic bromophenols 3,3′-dibromo-6,6′-dihydroxydiphenylmethane (13) and 3,3′,5,5′-tetrabromo-6,6′-dihydroxydiphenylmethane (14) showed potent antibacterial effect against Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Proteus vulgaris, and Salmonella typhimurium. [Copyright &y& Elsevier]

Abstract: Four aaptamines (1–4), 1H-benzo[de][1,6]-naphthyridine alkaloids, were isolated from the marine sponge Aaptos aaptos and their inhibitory activities against sortase A (SrtA), an enzyme that plays a key role in cell wall protein anchoring and virulence in Staphylococcus aureus, were evaluated. Isoaaptamine (2) was a potent inhibitor of SrtA, with an IC50 value of 3.7±0.2μg/mL. The suppression of fibronectin-binding activity by isoaaptamine (2) highlights its potential for the treatment of S. aureus infections via inhibition of SrtA activity. Our studies have identified a series of SrtA inhibitors, providing the basis for further development of potent inhibitors. [Copyright &y& Elsevier]

A facile and efficient method has been developed for the synthesis of novel thiazolyl carboxamide derivatives by direct reaction of the corresponding esters and 2-aminothiazole. Treatment of 2-aminothiozole with various carboxylic esters in the presence of t -butylmagnesium chloride provides the biologically significant thiazolyl carboxamide derivatives in good to excellent yields. [ABSTRACT FROM AUTHOR]

Three furan-containing scalarane sesterterpenoids (1–3) and a novel pyrrole-containing analog (4) were isolated from the sponge Scalarispongia species. Compound 3, reported in the literature as a synthetic derivative of furoscalarol 2, was for the first time isolated from a natural source. During the separation performed using a silica column in the presence of methanol, 16-methoxy derivatives (5, 6) were obtained from the unintended reaction of 2. The isolated natural products 3 and 4 and the artifact 5 showed moderate to high cytotoxicity against six human cancer cell lines, whereas compound 6, the C-16 epimer of 5, showed no cytotoxicity at a concentration of 60 μΜ. [ABSTRACT FROM AUTHOR]

An abstract of the article "Total Synthesis and Configurational Validation of (+)-Violapyrone C" by Jong Seok Lee and colleagues is presented.

[isolation, structure determination and cytotoxicity of three new 5-hydroxyindole alkaloids, i.e. [ABSTRACT FROM AUTHOR]

Isolation and structure elucidation of three new macrolactins (I)-(III) are described. [ABSTRACT FROM AUTHOR]

The new halenaquinone derivative (I) is isolated from the extract of the Micronesian marine sponge of the genus Xestospongia along with seven known related polyketides. [ABSTRACT FROM AUTHOR]