Antimicrobial metabolite of Cordyceps tenuipes targeting MurE ligase and histidine kinase via in silico study.

Cordyceps spp. are widely healthy foods around the world with several traditional uses and bio-functionalities. The chemical characterization of ethyl acetate-soluble extract of the entomopathogenic fungus Cordyceps tenuipes NBRC 111,630 afforded two new metabolites with 1,6-dioxaspiro[4.4]nonane motif, tenuipesone A (1) and tenuipesone B (2), along with four well-known metabolites (3-6). The elucidation of the chemical structures was carried out via extensive spectroscopic experiments including FTIR, HRMS, 1D-NMR, and 2D-NMR. The probable biosynthetic pathway of 1 and 2 was hypothesized. From the six isolates, beauvericin (6) exhibited antimicrobial activity against Bacillus subtilis and Staphylococcus aureus with respective MIC of 6.25 and 12.5 µM. Docking results exhibited that beauvericin (6) has significant binding affinities against MurE and HK proteins with ΔG = - 8.021 and - 8.585 kcal/mol, respectively. KEY POINTS: • Six compounds, including two new, were isolated from the entomopathogenic fungus Cordyceps tenuipes. • Plausible biosynthetic pathway of compounds 1, 2, 4, and 5 was hypothesized. • Beauvericin (6) exhibited significant antimicrobial activity against Bacillus subtilis and Staphylococcus aureus alongside binding affinities against MurE and HK proteins in MOE study.

A Concise Total Synthesis of Dehydroantofine and Its Antimalarial Activity against Chloroquine-Resistant Plasmodium falciparum.

The total synthesis of dehydroantofine was achieved by employing a novel, regioselective, azahetero Diels-Alder reaction of easily accessible 3,5-dichloro-2H-1,4-oxazin-2-one with 14 a as a key step. Furthermore, it is demonstrated that dehydroantofine is a promising candidate as a new antimalarial agent in a biological assay with chloroquine-resistant Plasmodium falciparum.

Design and synthesis of dual active neovibsanin derivatives based on a chemical structure merging method.

A hybrid compound consisting of neovibsanin and trans-banglene was designed according to a structure merging method and synthesized via a sequence of key steps including a Diels-Alder cycloaddition, stereoselective alkynylation, and intramolecular oxa-Michael addition reaction. The biological activity of the synthetized acetal compound and its hemiacetal analogue was investigated in PC12 cells. These studies revealed that the designed hybrid compounds displayed neuritogenic activity. Furthermore, a relatively strong neurite outgrowth promoting activity was observed in the presence of NGF. These results suggest that the designed hybrid compound exhibited a dual activity.

Asymmetric Total Syntheses and Structure Elucidations of (+)-Eurotiumide F and (+)-Eurotiumide G.

Asymmetric total syntheses of dihydropyran containing natural products, (+)-eurotiumide F and (+)-eurotiumide G have been described. These total syntheses revealed the absolute configuration of eurotiumide F and G, and confirmed the reported structure of eurotiumide F and revised the reported structure of eurotiumide G. Highlight of these syntheses is thermal rearrangement with 4-methoxyisochroman-1-one derivative having propargyl ether on phenolic ether under thermal condition to construct dihydropyran ring. X-Ray crystallographic analysis of (+)-eurotiumide G clarified the stereochemistry at the C1-position.

Marylosides A-G, Norcycloartane Glycosides from Leaves of Cymbidium Great Flower 'Marylaurencin'.

Seven novel norcycloartane glycosides, maryloside A-G (1-7), were isolated from the leaves of Cymbidium Great Flower 'Marylaurencin', along with a known norcycloartane glycoside, cymbidoside (8). These structures were determined on the basis of mainly NMR experiments as well as chemical degradation and X-ray crystallographic analysis. The isolated compounds (1-6 and 8) were evaluated for the inhibitory activity on lipopolysaccharide (LPS) and interferon-γ (IFN-γ)-stimulated nitric oxide (NO) production in RAW 264.7 cells. Consequently, 1 and 3 exhibited moderate activity.

Vizantin inhibits endotoxin-mediated immune responses via the TLR 4/MD-2 complex.

Vizantin has immunostimulating properties and anticancer activity. In this study, we investigated the molecular mechanism of immune activation by vizantin. THP-1 cells treated with small interfering RNA for TLR-4 abolished vizantin-induced macrophage activation processes such as chemokine release. In addition, compared with wild-type mice, the release of MIP-1ß induced by vizantin in vivo was significantly decreased in TLR-4 knockout mice, but not in TLR-2 knockout mice. Vizantin induced the release of IL-8 when HEK293T cells were transiently cotransfected with TLR-4 and MD-2, but not when they were transfected with TLR-4 or MD-2 alone or with TLR-2 or TLR-2/MD-2. A dipyrromethene boron difluoride-conjugated vizantin colocalized with TLR-4/MD-2, but not with TLR-4 or MD-2 alone. A pull-down assay with vizantin-coated magnetic beads showed that vizantin bound to TLR-4/MD-2 in extracts from HEK293T cells expressing both TLR-4 and MD-2. Furthermore, vizantin blocked the LPS-induced release of TNF-α and IL-1ß and inhibited death in mice. We also performed in silico docking simulation analysis of vizantin and MD-2 based on the structure of MD-2 complexed with the LPS antagonist E5564; the results suggested that vizantin could bind to the active pocket of MD-2. Our observations show that vizantin specifically binds to the TLR-4/MD-2 complex and that the vizantin receptor is identical to the LPS receptor. We conclude that vizantin could be an effective adjuvant and a therapeutic agent in the treatment of infectious diseases and the endotoxin shock caused by LPS.

Chemical Hybridization of Vizantin and Lipid A to Generate a Novel LPS Antagonist.

Lipopolysaccharide (LPS) antagonists have attracted considerable interest as promising candidates for the treatment of severe sepsis triggered by Gram-negative bacteria. In this article, we describe the development of a novel LPS antagonist based on chemical hybridization of vizantin and the hydrophobic molecular unit of LPS (lipid A). Vizantin, 6,6'-bis-O-(3-nonyldodecanoyl)-α,α'-trehalose, was designed as an immunostimulator from a structure-activity relationship (SAR) study with trehalose 6,6'-dicorynomycolate (TDCM). Our recent study indicated that vizantin displays adjuvant activity by specifically binding to the Toll-like receptor 4 (TLR4)/MD2 protein complex. Because lipid A unit (or LPS) is also known to trigger an inflammatory response via the same TLR4/MD2 complex as vizantin, we designed a hybrid compound of vizantin and lipid A with the aim of developing a novel biofunctional glycolipid. Focusing on the antagonism to Escherichia coli LPS in an in vitro model with human macrophages (THP-1 cells), we identified a potent LPS antagonist among the synthesized hybrid compounds. The novel LPS antagonist effectively inhibited LPS-induced release of tumor necrosis factor-alpha (TNF-α) in a dose-dependent manner with an IC50 value of 3.8 nM, making it a candidate for the treatment drug of Gram-negative sepsis and/or septic shock.

A new polyoxygenated cyclohexene and a new megastigmane glycoside from Uvaria grandiflora.

A new polyoxygenated cyclohexene, (-)-3-O-debenzoylzeylenone (1), and a new megastigmane glycoside, grandionoside A (2), were isolated from the aerial parts of Uvaria grandiflora collected in Vietnam, together with ten known compounds including polyoxygenated cyclohexenes (3-6), a triterpenoid (7), an alkaloid (8), a long chain alcohol (9), hexenyl glycopyranoside (10), and saponins (11-12). Their chemical structures were elucidated by a combination of extensive NMR spectroscopy with X-ray crystallographic analysis for 1, and chemical conversion for 2. Compound 1 exhibited significant cytotoxicity against the LU-1 and SK-Mel-2 cell lines with IC50 values of 4.68 and 3.63 µM, respectively. Remarkably, the cytotoxicity of 12 against the LU-1, KB, Hep-G2, MKN-7, and SW-480 cell lines was comparable to that of ellipticine, the positive control, with IC50 values ranging from 1.24 to 1.60 µM.

Kaempulchraols A-H, Diterpenoids from the Rhizomes of Kaempferia pulchra Collected in Myanmar.

Eight new diterpenoids, kaempulchraols A-H (1-8), along with five known analogues were isolated from the CHCl3-soluble extract of rhizomes of Kaempferia pulchra of Myanmar. The structures of these compounds were elucidated using extensive spectroscopic techniques including X-ray diffraction analysis. All the isolates were tested for their antiproliferative activity against a panel of five human cancer cell lines (A549, human lung cancer; HeLa, human cervix cancer; PANC-1 and PSN-1, human pancreatic cancer; MDA-MB-231, human breast cancer) and TIG-3, normal human primary fibroblast cells. Kaempulchraol F (6) exhibited weak activity against the human pancreatic PSN-1 cell line with an IC50 value of 12.3 µM.

Total synthesis of (-)-thallusin: utilization of enzymatic hydrolysis resolution.

(-)-Thallusin, isolated from a marine bacterium, is the only known natural product to act as an algal morphogenesis inducer. Because (-)-thallusin can only be obtained in exceedingly limited amounts from microbial cultivation, a synthetic supply of this compound is highly desirable. Here, we describe a novel synthetic pathway to (±)-thallusin and the first asymmetric synthesis of (-)-thallusin utilizing the enzymatic hydrolysis resolution with the combination of lipase PS-30 and lipase M Amamo-10.

Novel inhibitor of bacterial sphingomyelinase, SMY-540, developed based on three-dimensional structure analysis.

CONTEXT: Bacterial sphingomyelinase (SMase) is thought to play a crucial role in bacterial evasion of the immune response during the early stages of infections. OBJECTIVE: The objective of this study was to predict the chemical structure required for competitive SMase inhibition, then synthesize and test the effect of potential inhibitors on the hydrolysis of sphingomyelin (SM) and protection against infection by Bacillus cereus. MATERIALS AND METHODS: We synthesized 10 potential SMase inhibitors, derivatives of RY221B-a analogues, based on predictions from three-dimensional structural analysis. We then tested the effect of these compounds on the inhibition of SM hydrolysis and protection of mice inoculated with B. cereus. RESULTS: One compound, SMY-540, displayed a strong inhibitory effect (IC50 = 0.8 µM) upon SMase and prevented mortality in mice. CONCLUSION: SMY-540 is an effective inhibitor of Bc-SMase and has potential for use in the development of drugs to treat infectious diseases caused by bacteria that produce SMase.

Estimation of inferior-superior vocal fold kinematics from high-speed stereo endoscopic data in vivo.

Despite being an indispensable tool for both researchers and clinicians, traditional endoscopic imaging of the human vocal folds is limited in that it cannot capture their inferior-superior motion. A three-dimensional reconstruction technique using high-speed video imaging of the vocal folds in stereo is explored in an effort to estimate the inferior-superior motion of the medial-most edge of the vocal folds under normal muscle activation in vivo. Traditional stereo-matching algorithms from the field of computer vision are considered and modified to suit the specific challenges of the in vivo application. Inferior-superior motion of the medial vocal fold surface of three healthy speakers is reconstructed over one glottal cycle. The inferior-superior amplitude of the mucosal wave is found to be approximately 13 mm for normal modal voice, reducing to approximately 3 mm for strained falsetto voice, with uncertainty estimated at σ ≈ 2 mm and σ ≈ 1 mm, respectively. Sources of error, and their relative effects on the estimation of the inferior-superior motion, are considered and recommendations are made to improve the technique.

Isolation of C-29 oxygenated oleanane triterpenoids and a (+)-muurolene type sesquiterpenoid from the fruiting bodies of Fuscoporia torulosa and their bioactivities.

Basidiomycetes with a wide variety of skeletons of secondary metabolites can be expected to be the source of new interesting biological compounds. During our research on basidiomycetes, two new C-29 oxygenated oleanane-type triterpenes (1 and 2) and torulosacid (3), a muurolene type sesquiterpenoid with a five-membered ether ring along with nine known compounds (4-12), were isolated from the MeOH extract of the fruiting bodies of Fuscoporia torulosa. The structures of 1-3 were determined by NMR and HREIMS analysis. Further studies on the stereochemistry of 3 were conducted using X-ray crystallographic analysis and comparison of experimental and calculated ECD spectra. In the antimicrobial assay of isolates, 1, 7, and 9 showed growth inhibitory activity against methicillin-resistant Staphylococcus aureus and other gram-positive strains. Isolation of oleanane type triterpenes from fungi including basidiomycetes, is a unique report that could lead to further isolation of new compounds and the discovery of unique biosynthetic enzymes.

Concise synthesis of a probe molecule enabling analysis and imaging of vizantin.

Trehalose 6,6'-dicorynomycolate (TDCM) was first characterized in 1963 as a cell surface glycolipid of Corynebacterium spp. by Ioneda and co-workers. TDCM shows potent anti-tumor activity due to its immunoadjuvant properties. Furthermore, the toxicity of TDCM in mice is much weaker than the related trehalose diester of mycolic acid; trehalose 6,6'-dimycolate (TDM, formerly known as cord factor). We have investigated the chemical modification of this class of compound to generate novel agents that display increased immunoadjuvant activity with minimal associated toxicity. During the course of this work we recently developed 6,6'-bis-O-(3-nonyldodecanoyl)-α,α'-trehalose (designated as vizantin). Our results show that vizantin exhibited a potent prophylactic effect on experimental lung metastasis of B16-F0 melanoma cells without a loss of body weight and death in mice. Furthermore, vizantin effectively stimulated human macrophages in an in vitro model, making it a promising candidate for a safe adjuvant in clinical applications. In order to elucidate the pharmacokinetics of vizantin, a probe molecule with similar activity was developed on the basis of a structure-activity relationship (SAR) study with vizantin. The distribution of the probe molecule after intravenous administration into a mouse was assessed by macro confocal microscopy, where it was found to accumulate in the lungs and liver.

Yellow pigments, fomitellanols A and B, and drimane sesquiterpenoids, cryptoporic acids P and Q, from Fomitella fraxinea and their inhibitory activity against COX and 5-LO.

Yellow pigments, fomitellanols A (1a) and B (2a), and drimane-type sesquiterpenoid ethers of isocitric acid, cryptoporic acids P (3) and Q (4), have been isolated from the fruiting bodies of Fomitella fraxinea (Polyporaceae). Their structures were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analyses, and their biological activity against COX-1, COX-2, and 5-LO was investigated.

Report on the 1st and 2nd Japan Young Psychiatrists Organization Online International Networking Meetings (JOIN meetings) in 2021 and 2022.

Since 2002, the Japan Young Psychiatrists Organization (JYPO) has conducted an annual face-to-face Course for Academic Development of Psychiatrists (CADP). Since 2021, we held two international online meetings and studied whether it was possible to acquire professional and leadership skills. We found that participants were able to acquire knowledge and become acquainted with professional and leadership skills in online meetings. However, they didn't enough enable participants to get to know each other, develop friendships, or acquire professional and leadership skills. The advantages of online meetings included lower cost, avoiding infection during the pandemic, and the easy use of course materials.

Ternifolipyrons A-J: new cytotoxic α-pyrones from Isodon ternifolius (D. Don) Kudô.

Isodon ternifolius (D.Don) Kudô is an important Asian herb used in traditional medicine against several diseases. Nineteen compounds were isolated from the dichloromethane-methanol (1 : 1) extract of I. ternifolius roots, including ten new α-pyrone derivatives, named ternifolipyrons A-J. The chemical structures of the isolates were determined by a combination of 1D and 2D NMR, along with LR- and HRMS spectroscopy. The absolute configurations of the α-pyrone derivatives were constructed based upon the X-ray signal crystal of the bromobenzoyl derivative of 1 as well as the electronic circular dichroism (ECD). All isolates (1-19) were investigated for their growth-inhibitory potential towards CCRF-CEM-leukemia cells at a fixed concentration of 30 µM. The compounds which exerted more than 50% inhibition at this concentration, compounds (7, 10, 12, 15-17), were tested at a different concentration range to determine their IC50 values in CCRF-CEM leukemia, MDA-MB-231 triple-negative breast cancer, and MCF7 breast cancer cell lines. Ursolic acid (16) showed the most potent activity against the three cancer cell lines with IC50 values of 8.37, 18.04, and 18.93 µM, respectively.

Bifusicoumarins A-D: Cytotoxic 3S-dihydroisocoumarins from the entomopathogenic fungus Cordyceps bifusispora (NBRC 108997).

Cordyceps is a genus of ascomycete fungi with some of them being edible and/or having a long tradition in Chinese medicine. The chemical characterization of a solvent extract of the entomopathogenic fungus Cordyceps bifusispora afforded four undescribed coumarins, bifusicoumarin A-D (1-4), along with previously reported metabolites (5-8). Structural elucidation was performed via NMR, UV and HRMS analyses, X-ray single crystal diffraction and experimental ECD. A high throughput resazurin reduction assay, that measures cell viability, indicated that 5 has a IC50 between 1 and 15 µM for several assayed tumor lines. Moreover, a protein-interaction network indicated that C. bifusispora is a promising source of additional antitumor metabolites based on SwissTargetPrediction software predictions.

Syntheses of structurally-simplified and fluorescently-labeled neovibsanin derivatives and analysis of their neurite outgrowth activity in PC12 cells.

The syntheses of several neovibsanin derivatives were carried out in order to elucidate the simple structure required for displaying neurite outgrowth activity. In addition, a fluorescent probe molecule was synthesized and the analysis of its behavior in the PC12 cell line showed that the neovibsanins accumulate on the outer edge of the cell at the site of formation of prominences.

Phenanthrene derivatives from Cymbidium Great Flower Marie Laurencin and their biological activities.

A new phenanthrendione, ephemeranthoquinone B (1), two phenanthrenes, marylaurencinols A (2) and B (3), and a phenanthrene glucoside, marylaurencinoside A (4), were isolated from the roots of Cymbidium Great Flower Marie Laurencin, along with six known phenanthrenes, 5-10. The structures of these compounds were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analysis and chemical degradation. The compounds were tested for antibacterial activities against Bacillus subtilis and Klebsiella pneumoniae and for cytotoxic activity against the human promyelocytic leukemia (HL-60) cell line. Compounds 1, 3, and 6 showed antibacterial activities with minimum inhibitory concentration (MIC) values in the range of 4.88 to 65.10 µM. Notably, ephemeranthoquinone B (1) had a strong antibacterial effect on B. subtilis. Furthermore, 1 exhibited moderate cytotoxic activity (IC(50) 2.8 µM) against HL-60 cells. Compounds 4-9 also showed weak cytotoxic activity against the HL-60 cell line with IC(50) values of 19.3-52.4 µM.