Improved Quantification of Geosmin and 2-Methylisoborneol in Farmed Fish Using Stable Isotope Dilution Gas Chromatography-Mass Spectrometry.

A requisite to improving the taste and odor attributes of farmed fish is the availability of accurate and practical analytical methods to quantify 2-methylisoborneol (MIB) and geosmin (GSM). Solid-phase microextraction (SPME) enables reliable measurement of nanogram per liter quantities of MIB and GSM in water. In contrast, direct headspace (HS)-SPME of biological matrices with variable proximate compositions can increase bias and uncertainty in off-flavor determinations. Analytical recovery plays a crucial role in the accurate determination of MIB and GSM in fish, and this study investigates strategies to maximize and account for this recovery factor. MIB and GSM values in off-flavor catfish and trout were measured using direct HS-SPME and distillation as sample preparation techniques. Trout samples prepared by distillation yielded 10-fold higher GSM recoveries than those from direct HS-SPME (31% versus 3%). A stable isotope dilution method (SIDM) was implemented by routinely spiking samples with known quantities of deuterium-labeled MIB and GSM, allowing for the correction of sample-to-sample recovery deviations. SIDM-determined GSM values generated recoveries of 106 and 95% for direct HS-SPME and distilled trout, respectively. Aspects of the strategies and techniques presented can be incorporated into existing analytical methods to improve the accuracy and sample throughput. Particularly, routine inclusion of SIDM in the evaluation of MIB and GSM can facilitate identification of reliable practices to control off-flavors in aquaculture.

A naphthol hydrazone Schiff base bearing benzothiadiazole unit for fluorescent detection of Fe3+ in PC3 cells.

Naphthol hydrazone derivatives are recognized as efficient chelating agents for both qualitative and quantitative detection of metal ions. Here we design a naphthol hydrazine-based chemosensor with covalently linking a strong electron-withdrawing benzothiadiazole group to modulate the molecular electronic structure, nominated as NtHzBtd. The fluorescent probe performs excellent selectivity and sensitivity towards Fe3+ with 1:1 binding stoichiometry, while exhibiting a quick response at 55 s with a relatively low limit of detection of 0.036 µM. A series of spectroscopic measurements in tandem with theoretical calculations suggest that the probe undergoes both intramolecular charge transfer (ICT) and chelation enhanced quenching (CHEQ) processes. Successful color rendering of paper strips and bioimaging in PC3 cells demonstrate the promising applicability of NtHzBtd for portable Fe3+ detection in real samples and biosystems.

Recent advances in the green synthesis of Betti bases and their applications: a review.

Well-known Betti bases are the products obtained by the one-pot multicomponent reaction of 1-naphthol/2-naphthol, aliphatic/aromatic aldehydes, and secondary amines, and this reaction is known as the Betti reaction. During recent years, due to the unveiling of the pharmacological and synthetic potential of Betti bases, a tremendous increase in the studies reporting novel synthetic methods for the efficient synthesis of Betti bases was observed. This review presents the recent key developments in the green synthesis of the Betti bases and accounts for the significant number of the literature reported during 2019-2022. Both catalyst free as well as the catalyst promoted synthesis (nanocatalyst, biocatalyst, transition metal catalyst, etc.) along with the synthetic applications (catalyst, ligands/chiral auxiliaries, and valuable synthons), optoelectronic applications (fluorescence sensors for phosgene gas, Hg2+, and Cr3+ detection, quasi-reversible redox potential) and biological properties (anticancer agents, antioxidant, anti-inflammatory agents, antitubercular agents, pesticidal agents, anti-Alzheimer agents, Topoisomerase I inhibitors, YAP-TEAD interaction inhibitors, and DNA binding and cleavage activity) are discussed. There is a surge of interest for the development of the green and efficient Betti reaction for the construction of C-C and C-N bond in a single-step reaction accessing Betti bases as products. Along with key methodological developments for the green synthesis of Betti bases, their applications in synthetic organic chemistry, optoelectronic sensors, advanced materials synthesis, agrochemicals and pharmaceutically active scaffolds, during the period of 2019-2022, have been considered.

Citreobenzofuran D-F and Phomenone A-B: Five Novel Sesquiterpenoids from the Mangrove-Derived Fungus Penicillium sp. HDN13-494.

Five new sesquiterpenoids, citreobenzofuran D-F (1-3) and phomenone A-B (4-5), along with one known compound, xylarenone A (6), were isolated from the culture of the mangrove-derived fungus Penicillium sp. HDN13-494. Their structures were deduced from extensive spectroscopic data, high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) calculations. Furthermore, the absolute structures of 1 were determined by single-crystal X-ray diffraction analysis. Citreobenzofuran E-F (2-3) are eremophilane-type sesquiterpenoids with rare benzofuran frameworks, while phomenone A (4) contains a rare thiomethyl group, which is the first report of this kind of sesquiterpene with sulfur elements in the skeleton. All the compounds were tested for their antimicrobial and antitumor activity, and phomenone B (5) showed moderate activity against Bacillus subtilis, with an MIC value of 6.25 µM.

Discovery of novel rigid analogs of 2-naphthol with potent anticancer activity through multi-target topoisomerase I & II and tyrosine kinase receptor EGFR & VEGFR-2 inhibition mechanism.

A novel oxygen-containing heterocyclic linked 1H-benzo[f]chromene moieties (4a-g) and (6a-g) with anti-proliferative activity against cancer cell lines was designed, synthesized, and established on the basis of spectral data. All the prepared compounds were evaluated in vitro for their anti-proliferative activity against MCF-7, HCT-116, HepG-2 cell lines and normal cell lines HFL-1, WI-38. Compounds 4a, 4b, and 6e exhibited good activity against MCF-7, HCT-116, and HepG-2 cell lines, comparable to that of Vinblastine and Doxorubicin, and weak active against normal cell lines. Moreover, the potential mechanisms of the cytotoxic activity of the promising compounds 4a, 4b, and 6e on the more sensitive cell line MCF-7 were studied. We found that compounds 4a, 4b, and 6e induce cell cycle arrest at G2/M phases for MCF-7 treated cells compared to untreated cells, which causes apoptosis and inhibits both the topoisomerase I and II enzymes. In addition, compounds 4a and 4b exhibited comparable inhibitory activity on tyrosine kinase receptors EGFR and VEGFR-2 kinases to that of the reference protein kinases inhibitor Sorafenib. The in silico molecular docking of the most active compounds into the active sites of EGFR kinase and Topo I & II enzymes provides us with a reasonable clarification of the interpreted biological data.

MHY2245, a Sirtuin Inhibitor, Induces Cell Cycle Arrest and Apoptosis in HCT116 Human Colorectal Cancer Cells.

Sirtuins (SIRTs), which are nicotinamide adenine dinucleotide-dependent class III histone deacetylases, regulate cell division, survival, and senescence. Although sirtinol, a synthetic SIRT inhibitor, is known to exhibit antitumor effects, its mechanism of action is not well understood. Therefore, we aimed to assess the anticancer effects and underlying mechanism of MHY2245, a derivative of sirtinol, in HCT116 human colorectal cancer cells in vitro. Treatment with MHY2245 decreased SIRT1 activity and caused DNA damage, leading to the upregulation of p53 acetylation, and increased levels of p53, phosphorylation of H2A histone family member X, ataxia telangiectasia and Rad3-related kinase, checkpoint kinase 1 (Chk1), and Chk2. The level of the breast cancer type 1 susceptibility protein was also found to decrease. MHY2245 induced G2/M phase cell cycle arrest via the downregulation of cyclin B1, cell division cycle protein 2 (Cdc2), and Cdc25c. Further, MHY2245 induced HCT116 cell death via apoptosis, which was accompanied by internucleosomal DNA fragmentation, decreased B-cell lymphoma 2 (Bcl-2) levels, increased Bcl-2-asscociated X protein levels, cleavage of poly(ADP-ribose) polymerase, and activation of caspases -3, -8, and -9. Overall, MHY2245 induces cell cycle arrest, triggers apoptosis through caspase activation, and exhibits DNA damage response-associated anticancer effects.

Quantification of bone marrow interstitial pH and calcium concentration by intravital ratiometric imaging.

The fate of hematopoietic stem cells (HSCs) can be directed by microenvironmental factors including extracellular calcium ion concentration ([Ca2+]e), but the local [Ca2+]e around individual HSCs in vivo remains unknown. Here we develop intravital ratiometric analyses to quantify the absolute pH and [Ca2+]e in the mouse calvarial bone marrow, taking into account the pH sensitivity of the calcium probe and the wavelength-dependent optical loss through bone. Unexpectedly, the mean [Ca2+]e in the bone marrow (1.0 ± 0.54 mM) is not significantly different from the blood serum, but the HSCs are found in locations with elevated local [Ca2+]e (1.5 ± 0.57 mM). With aging, a significant increase in [Ca2+]e is found in M-type cavities that exclusively support clonal expansion of activated HSCs. This work thus establishes a tool to investigate [Ca2+]e and pH in the HSC niche with high spatial resolution and can be broadly applied to other tissue types.

Virtual Screening and Molecular Docking to Study the Mechanism of Chinese Medicines in the Treatment of Coronavirus Infection.

BACKGROUND Heat-clearing and detoxifying herbs (HDHs) play an important role in the prevention and treatment of coronavirus infection. However, their mechanism of action needs further study. This study aimed to explore the anti-coronavirus basis and mechanism of HDHs. MATERIAL AND METHODS Database mining was performed on 7 HDHs. Core ingredients and targets were screened according to ADME rules combined with Neighborhood, Co-occurrence, Co-expression, and other algorithms. GO enrichment and KEGG pathway analyses were performed using the R language. Finally, high-throughput molecular docking was used for verification. RESULTS HDHs mainly acts on NOS3, EGFR, IL-6, MAPK8, PTGS2, MAPK14, NFKB1, and CASP3 through quercetin, luteolin, wogonin, indirubin alkaloids, ß-sitosterol, and isolariciresinol. These targets are mainly involved in the regulation of biological processes such as inflammation, activation of MAPK activity, and positive regulation of NF-kappaB transcription factor activity. Pathway analysis further revealed that the pathways regulated by these targets mainly include: signaling pathways related to viral and bacterial infections such as tuberculosis, influenza A, Ras signaling pathways; inflammation-related pathways such as the TLR, TNF, MAPK, and HIF-1 signaling pathways; and immune-related pathways such as NOD receptor signaling pathways. These pathways play a synergistic role in inhibiting lung inflammation and regulating immunity and antiviral activity. CONCLUSIONS HDHs play a role in the treatment of coronavirus infection by regulating the body's immunity, fighting inflammation, and antiviral activities, suggesting a molecular basis and new strategies for the treatment of COVID-19 and a foundation for the screening of new antiviral drugs.

Synthesis, crystal structure, and in vitro evaluation of the anticancer activity of new Pt (Pd) complexes with 1-[(dimethylamino)methyl]-2-naphthol ligand.

The synthesis of new Pt(II) and Pd(II) complexes with 1-aminomethyl-2-naphtol ligands has been first performed. The adducts of [PtCl4]2- and [PdCl4]2- anions with the 1-aminomethyl-2-naphtol NH cation were synthesized. The structure for four Pt (Pd)-containing compounds was investigated using X-ray diffraction. The obtained compounds were examined for in vitro cytotoxic activity against Jurkat and K562 human leukemia cells, lymphoma U937cells, A2780 and the cisplatin-resistant A2780cis lines of human ovarian cancer, and normal fibroblasts. Study of induction of apoptosis and the effect of new palladium and platinum complexes on the cell cycle was carried out. The cells showed a higher sensitivity to Pt(II) compounds than to Pd(II) ones. All the synthesized metal complexes show much more antitumor activity compared with a platinum-containing cisplatin drug.

Cladosporols A and B, two natural peroxisome proliferator-activated receptor gamma (PPARγ) agonists, inhibit adipogenesis in 3T3-L1 preadipocytes and cause a conditioned-culture-medium-dependent arrest of HT-29 cell proliferation.

BACKGROUND: Obesity and type 2 diabetes mellitus, which are widespread throughout the world, require therapeutic interventions targeted to solve clinical problems (insulin resistance, hyperglycaemia, dyslipidaemia and steatosis). Several natural compounds are now part of the therapeutic repertoire developed to better manage these pathological conditions. Cladosporols, secondary metabolites from the fungus Cladosporium tenuissimum, have been characterised for their ability to control cell proliferation in human colon cancer cell lines through peroxisome proliferator-activated receptor gamma (PPARγ)-mediated modulation of gene expression. Here, we report data concerning the ability of cladosporols to regulate the differentiation of murine 3T3-L1 preadipocytes. METHODS: Cell counting and MTT assay were used for analysing cell proliferation. RT-PCR and Western blotting assays were performed to evaluate differentiation marker expression. Cell migration was analysed by wound-healing assay. RESULTS: We showed that cladosporol A and B inhibited the storage of lipids in 3T3-L1 mature adipocytes, while their administration did not affect the proliferative ability of preadipocytes. Moreover, both cladosporols downregulated mRNA and protein levels of early (C/EBPα and PPARγ) and late (aP2, LPL, FASN, GLUT-4, adiponectin and leptin) differentiation markers of adipogenesis. Finally, we found that proliferation and migration of HT-29 colorectal cancer cells were inhibited by conditioned medium from cladosporol-treated 3T3-L1 cells compared with the preadipocyte conditioned medium. CONCLUSIONS: To our knowledge, this is the first report describing that cladosporols inhibit in vitro adipogenesis and through this inhibition may interfere with HT-29 cancer cell growth and migration. GENERAL SIGNIFICANCE: Cladosporols are promising tools to inhibit concomitantly adipogenesis and control colon cancer initiation and progression.

Photochemical Reactivity of Naphthol-Naphthalimide Conjugates and Their Biological Activity.

Quinone methide precursors 1a-e, with different alkyl linkers between the naphthol and the naphthalimide chromophore, were synthesized. Their photophysical properties and photochemical reactivity were investigated and connected with biological activity. Upon excitation of the naphthol, Förster resonance energy transfer (FRET) to the naphthalimide takes place and the quantum yields of fluorescence are low (ΦF ≈ 10-2). Due to FRET, photodehydration of naphthols to QMs takes place inefficiently (ΦR ≈ 10-5). However, the formation of QMs can also be initiated upon excitation of naphthalimide, the lower energy chromophore, in a process that involves photoinduced electron transfer (PET) from the naphthol to the naphthalimide. Fluorescence titrations revealed that 1a and 1e form complexes with ct-DNA with moderate association constants Ka ≈ 105-106 M-1, as well as with bovine serum albumin (BSA) Ka ≈ 105 M-1 (1:1 complex). The irradiation of the complex 1e@BSA resulted in the alkylation of the protein, probably via QM. The antiproliferative activity of 1a-e against two human cancer cell lines (H460 and MCF 7) was investigated with the cells kept in the dark or irradiated at 350 nm, whereupon cytotoxicity increased, particularly for 1e (>100 times). Although the enhancement of this activity upon UV irradiation has no imminent therapeutic application, the results presented have importance in the rational design of new generations of anticancer phototherapeutics that absorb visible light.

Antiproliferative Properties and G-Quadruplex-Binding of Symmetrical Naphtho[1,2-b:8,7-b']dithiophene Derivatives.

Background: G-quadruplex (G4) forming sequences are recurrent in telomeres and promoter regions of several protooncogenes. In normal cells, the transient arrangements of DNA in G-tetrads may regulate replication, transcription, and translation processes. Tumors are characterized by uncontrolled cell growth and tissue invasiveness and some of them are possibly mediated by gene expression involving G-quadruplexes. The stabilization of G-quadruplex sequences with small molecules is considered a promising strategy in anticancer targeted therapy. Methods: Molecular virtual screening allowed us identifying novel symmetric bifunctionalized naphtho[1,2-b:8,7-b']dithiophene ligands as interesting candidates targeting h-Telo and c-MYC G-quadruplexes. A set of unexplored naphtho-dithiophene derivatives has been synthesized and biologically tested through in vitro antiproliferative assays and spectroscopic experiments in solution. Results: The analysis of biological and spectroscopic data highlighted noteworthy cytotoxic effects on HeLa cancer cell line (GI50 in the low µM range), but weak interactions with G-quadruplex c-MYC promoter. Conclusions: The new series of naphtho[1,2-b:8,7-b']dithiophene derivatives, bearing the pharmacophoric assumptions necessary to stabilize G-quadruplexes, have been designed and successfully synthesized. The interesting antiproliferative results supported by computer aided rational approaches suggest that these studies are a significant starting point for a lead optimization process and the isolation of a more efficacious set of G-quadruplexes stabilizers.

Design, Synthesis, and Molecular Docking of Paracyclophanyl-Thiazole Hybrids as Novel CDK1 Inhibitors and Apoptosis Inducing Anti-Melanoma Agents.

Three new series of paracyclophanyl-dihydronaphtho[2,3-d]thiazoles and paracyclophanyl-thiazolium bromides were designed, synthesized, and characterized by their spectroscopic data, along with X-ray analysis. One-dose assay results of anticancer activity indicated that 3a-e had the highest ability to inhibit the proliferation of different cancer cell lines. Moreover, the hybrids 3c-e were selected for five-dose analyses to demonstrate a broad spectrum of antitumor activity without apparent selectivity. Interestingly, series I compounds (Z)-N-substituted-4,9-dihydronaphtho[2,3-d]thiazol-3(2H)-yl)-4'-[2.2]paracyclophanylamide) that are carrying 1,4-dihydronaphthoquinone were more active as antiproliferative agents than their naphthalene-containing congeners (series II: substituted 2-(4'-[2.2]paracyclophanyl)hydrazinyl)-4-(naphth-2-yl)-thiazol-3-ium bromide hybrids) and (series III: 3-(4'-[2.2]paracyclophanyl)amido-2-(cyclopropylamino)-4-(naphth-2-yl)thiazol-3-ium bromide) toward the SK-MEL-5 melanoma cell line. Further antiproliferation investigations of 3c and 3e on the healthy, normal unaffected SK-MEL-5 cell line indicated their relative safety. Compound 3c showed an inhibition of eight isoforms of cyclin-dependent kinases (CDK); however, it exhibited the lowest IC50 of 54.8 nM on CDK1 in comparison to Dinaciclib as a reference. Additionally, compound 3c revealed a remarkable downregulation of phospho-Tyr15 with a level (7.45 pg/mL) close to the reference. 3c mainly showed cell cycle arrest in the pre-G1 and G2/M phases upon analysis of the SK-MEL-5 cell line. The sequential caspase-3 assay for 3c indicated a remarkable overexpression level. Finally, a molecular docking study was adopted to elucidate the binding mode and interactions of the target compounds with CDK1.

Luminescent Chemosensor Based on Ru(II) Bipyridine Complex for Detection of Sudan I through Inner Filter Effect.

Presence of Sudan I in food stuff can be problematic and need to be checked in order to protect our health from possible carcinogen. Therefore, it is essential to detect Sudan I by efficient, rapid and reliable method. In this work, we have designed a Ru(II) polypyridyl complex, [Ru(bpy)2(CIP)]2+ probe for the selective and sensitive detection of Sudan I. Upon addition of Sudan I to the solution of [Ru(bpy)2(CIP)]2+ in ethanol, the luminescence quenched rapidly, and linear concentration range with analyte has been obtained from 0.8 to 100 µM with the limit of detection as low as 0.26 µM (S/N = 3). The effective luminescence quenching was resulted due to the inner filter effect (IFE) between luminophore, [Ru(bpy)2(CIP)]2+ and quencher, Sudan I. Our spectroscopic study was essentially provided sufficient analytical evidences in order to prove occurrence of IFE mechanism. As there were no interferences observed in luminescence measurement from the other substances the present probe has been successfully applied for the detection of Sudan I in commercial chili powder sample, making the probe suitable for practical usage.

Simple and reliable method to simultaneously determine urinary 1- and 2-naphthol using in situ derivatization and gas chromatography-mass spectrometry for biological monitoring of naphthalene exposure in occupational health practice.

OBJECTIVES: The aim of this study was to develop and validate a simple and reliable gas chromatography-mass spectrometry (GC-MS) method to simultaneously determine urinary 1-naphthol (1-NAP) and 2-naphthol (2-NAP) for biological monitoring of occupational exposure to naphthalene. METHODS: NAPs were derivatized in situ with acetic anhydride after enzymatic hydrolysis, extracted with n-hexane, and analyzed using GC-MS. Validation of the proposed method was conducted in accordance with US Food and Drug Administration guidance. A final validation was performed by analyzing a ClinChek® -Control for phenolic compounds. RESULTS: The linearity of calibration curves was indicated by a high correlation coefficient (>0.999) in the concentration range 1-100 µg/L for each NAP. The limits of detection and quantification for each NAP were 0.30 and 1.00 µg/L, respectively. The recovery was 90.8%-98.1%. The intraday and interday accuracies, expressed as the deviation from the nominal value, were 92.2%-99.9% and 93.4%-99.9%, respectively. The intraday and interday precision, expressed as the relative standard deviation, was 0.3%-3.9% and 0.4%-4.1%, respectively. The ClinChek® values obtained using our method were sufficiently accurate. CONCLUSIONS: The proposed method is simple, reliable, and appropriate for routine analyses, and is useful for biological monitoring of naphthalene exposure in occupational health practice.

2-Naphthol Moiety of Neocarzinostatin Chromophore as a Novel Protein-Photodegrading Agent and Its Application as a H2 O2 -Activatable Photosensitizer.

A 2-naphthol derivative 2 corresponding to the aromatic ring moiety of neocarzinostatin chromophore was found to degrade proteins under photo-irradiation with long-wavelength UV light without any additives under neutral conditions. Structure-activity relationship studies of the derivative revealed that methylation of the hydroxyl group at the C2 position of 2 significantly suppressed its photodegradation ability. Furthermore, a purpose-designed synthetic tumor-related biomarker, a H2 O2 -activatable photosensitizer 8 possessing a H2 O2 -responsive arylboronic ester moiety conjugated to the hydroxyl group at the C2 position of 2, showed significantly lower photodegradation ability compared to 2. However, release of the 2 from 8 by reaction with H2 O2 regenerated the photodegradation ability. Compound 8 exhibited selective photo-cytotoxicity against high H2 O2 -expressing cancer cells upon irradiation with long-wavelength UV light.

Ring-Substituted 1-Hydroxynaphthalene-2-Carboxanilides Inhibit Proliferation and Trigger Mitochondria-Mediated Apoptosis.

Ring-substituted 1-hydroxynaphthalene-2-carboxanilides were previously investigated for their antimycobacterial properties. In our study, we have shown their antiproliferative and cell death-inducing effects in cancer cell lines. Cell proliferation and viability were assessed by WST-1 assay and a dye exclusion test, respectively. Cell cycle distribution, phosphatidylserine externalization, levels of reactive oxygen or nitrogen species (RONS), mitochondrial membrane depolarization, and release of cytochrome c were estimated by flow cytometry. Levels of regulatory proteins were determined by Western blotting. Our data suggest that the ability to inhibit the proliferation of THP-1 or MCF-7 cells might be referred to meta- or para-substituted derivatives with electron-withdrawing groups -F, -Br, or -CF3 at anilide moiety. This effect was accompanied by accumulation of cells in G1 phase. Compound 10 also induced apoptosis in THP-1 cells in association with a loss of mitochondrial membrane potential and production of mitochondrial superoxide. Our study provides a new insight into the action of salicylanilide derivatives, hydroxynaphthalene carboxamides, in cancer cells. Thus, their structure merits further investigation as a model moiety of new small-molecule compounds with potential anticancer properties.

Development of a Reversible Indicator Displacement Assay Based on the 1-(2-Pyridylazo)-2-naphthol for Colorimetric Determination of Cysteine in Biological Samples and Its Application to Constructing the Paper Test Strips and a Molecular-Scale Set/Reset Memorized Device.

A new colorimetric chemosensor for naked-eye detection and determination of cysteine (Cys) based on indicator displacement assay (IDA) was designed using 1-(2-pyridylazo)-2-naphthol (PAN). The indicator exchange occurred between PAN and Cys by the addition of Cys to the Cu(PAN)2 complex, which is accomplished by an immediate visible color change from magenta to yellow, in the solution phase and paper-based test strips. The proposed method exhibits 0.35 µmol L-1 detection limit and good linearity in the range of 2.25-42.91 µmol L-1. Paper test strips presented a detection limit of 38.0 µmol L-1, fabricating an easy to use test kit for compatible "in-the-field" detection of Cys. The computer image analysis of the paper test strips, obtained from the CMYK color analysis system, showed a linear increase in Y (yellow) intensity with enhancement in the Cys concentration of 50.0-550.0 µmol L-1. Additionally, the absorption and color change obtained in this chemosensor operate as an "INHIBIT" logic gate considering Cu2+ and Cys as inputs. Eventually, based on such a fast, reversible, and reproducible signal, a molecular-scale sequential memory unit was designed displaying "Writing-Reading-Erasing-Reading" and "Multi-Write" behavior. The developed chemosensor presented a satisfactory repeatability, intermediate precision, and successful application for the selective determination of Cys in human biological fluids. Graphical abstract .

Cohnella fermenti sp. nov., isolated from a fermentation process.

A novel Gram-stain-positive, aerobic, motile with peritrichous flagella, rod-shaped bacterium, designated CC-MHH1044T, was isolated from a preserved vegetable sample. A polyphasic taxonomic approach was applied to the isolates in order to clarify its taxonomic position. Growth of the strain CC-MHH1044T occurred at 15-50 °C (optimum, 30 °C), pH 6.0-8.0 (optimum, pH 7.0) and with 0-2.0 % (w/v) NaCl (optimum, 1 %, w/v). The genome of strain CC-MHH1044T consisted of 8.5 Mb and the genomic DNA G+C content was 58.5 mol%. Comparison of the 16S rRNA gene sequences showed that CC-MHH1044T belonged to the genus Cohnella and showed a close relationship with the type strains of Cohnella damuensis (96.2 %) and Cohnella panacarvi (95.9 %), and lower sequence similarity to other species. Average nucleotide identity values calculated from whole-genome sequencing data proved that CC-MHH1044T represents a distinct Cohnella species. The dominant cellular fatty acids (>5 %) included iso-C14 : 0(7.4 %), iso-C15 : 0 (6.4 %), anteiso-C15 : 0(40.3 %), C16 : 0 (6.6 %) and iso-C16 : 0 (27.0 %). The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified aminophospholipids, one unidentified phospholipid and glycolipid. The major polyamine was spermidine. The predominant isoprenoid quinone was menaqinone 7 (MK-7). Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits, together with results of comparative 16S rRNA gene sequence, average nucleotide identity and digital DNA-DNA hybridization analyses, we conclude that strain CC-MHH1044T represents a novel member of the genus Cohnella, for which the name Cohnella fermenti sp. nov. is proposed. The type strain is CC-MHH1044T (=BCRC 81147T=JCM 32834T).

Enantioselective Iron/Bisquinolyldiamine Ligand-Catalyzed Oxidative Coupling Reaction of 2-Naphthols.

An iron-catalyzed asymmetric oxidative homo-coupling of 2-naphthols for the synthesis of 1,1'-Bi-2-naphthol (BINOL) derivatives is reported. The coupling reaction provides enantioenriched BINOLs in good yields (up to 99%) and moderate enantioselectivities (up to 81:19 er) using an iron-complex generated in situ from Fe(ClO4)2 and a bisquinolyldiamine ligand [(1R,2R)-N1,N2-di(quinolin-8-yl)cyclohexane-1,2-diamine, L1]. A number of ligands (L2-L8) and the analogs of L1, with various substituents and chiral backbones, were synthesized and examined in the oxidative coupling reactions.