Integrative Proteomics and N-Glycoproteomics Analyses of Rheumatoid Arthritis Synovium Reveal Immune-Associated Glycopeptides.

Rheumatoid arthritis (RA) is a typical autoimmune disease characterized by synovial inflammation, synovial tissue hyperplasia, and destruction of bone and cartilage. Protein glycosylation plays key roles in the pathogenesis of RA but in-depth glycoproteomics analysis of synovial tissues is still lacking. Here, by using a strategy to quantify intact N-glycopeptides, we identified 1260 intact N-glycopeptides from 481 N-glycosites on 334 glycoproteins in RA synovium. Bioinformatics analysis revealed that the hyper-glycosylated proteins in RA were closely linked to immune responses. By using DNASTAR software, we identified 20 N-glycopeptides whose prototype peptides were highly immunogenic. We next calculated the enrichment scores of nine types of immune cells using specific gene sets from public single-cell transcriptomics data of RA and revealed that the N-glycosylation levels at some sites, such as IGSF10_N2147, MOXD2P_N404, and PTCH2_N812, were significantly correlated with the enrichment scores of certain immune cell types. Furthermore, we showed that aberrant N-glycosylation in the RA synovium was related to increased expression of glycosylation enzymes. Collectively, this work presents, for the first time, the N-glycoproteome of RA synovium and describes immune-associated glycosylation, providing novel insights into RA pathogenesis.

Micromechanism for Copper-Deficiency Enhanced Stability: A Quasi In Situ TEM Study of Electric-Induced Structural Evolution in Cu2-x(S, Se) Liquid-Like Thermoelectric Materials.

Cu-based liquid-like thermoelectric materials have garnered tremendous attention due to their inherent ultralow lattice thermal conductivity. However, their practical application is hampered by stability issues under a large current or temperature gradient. It has been reported that introduction of copper vacancies can enhance the chemical stability, whereas the micromechanism behind this macroscopic improvement still remains unknown. Here, we have established a quasi in situ TEM method to examine and compare the structural evolution of Cu2-xS0.2Se0.8 (x = 0, 0.05) under external electric fields. It is then found that the preset Cu vacancies could favor the electric-induced formation of a more stable intermediate phase, i.e., the hexagonal CuSe-type structure in the form of either lamellar defects (majorly) or long-range order (minorly), in which ordering of S and Se also occurred. Thereby, copper and chalcogen atoms could largely be solidified into the matrix, and the elemental deposition and evaporation process is mitigated under an electric field.

Effects of different concentrations and particle sizes of nanoplastics on gut microbiology, metabolism, and immunity in Chiromantes dehaani.

This study investigated the effects of nanoplastics (NPs) of varying particle sizes (75, 500, and 1000 nm) and concentrations (2.5 and 10 mg/L) on the gut health of Chiromantes dehaani. The experimental groups included a control (Cg0), and varying combinations of particle size and concentration. Our results showed that 75 nm NPs were more likely to enhance pathogenic bacterial growth than other sized NPs. Compared with CK, Low NPs concentrations (2.5 mg/L) raised total cholesterol (T-CHO) levels in the gut, while high concentrations significantly decreased both triglyceride (TG) and T-CHO levels (p < 0.05). The enzymatic activities of intestinal lipase and amylase were inhibited by NPs exposure, with greater inhibition at higher NPs concentrations. The 500 nm NPs exhibited a notably higher inhibitory effect than the 75 and 1000 nm NPs (P < 0.05). In terms of apoptosis, NPs exposure led to reduced mRNA expression of Bcl2 and increased expression of Caspase-3, Caspase-8, and Caspase-9, indicating an induction of apoptosis. This effect was more pronounced at higher NPs concentrations, with 75 nm NPs more likely to induce apoptosis in intestinal cells than 500 nm and 1000 nm NPs. Moreover, NPs triggered intestinal inflammatory responses, evidenced by the increased mRNA expression of TNF-ß, TNF-α, IL1ß, IL6, and IL8, and the decreased expression of IL10. High NPs concentrations were more likely to induce intestinal inflammation, with 500 nm NPs imparting the strongest effect. In summary, the study demonstrated that NPs, and particularly those at higher concentrations, disrupted the gut environment of C. dehaani by altering the microflora, reducing microbial diversity, inhibiting digestion and metabolism, inducing apoptosis, and triggering inflammation. Among the sizes of NPs tested, 500 nm NPs had the most significant adverse impact on digestion, metabolism, and inflammation, while 75 nm NPs most strongly induced apoptosis in C. dehaani's intestinal cells.

Accelerating the Hydrogen Production via Modifying the Fermi Surface.

The design of catalysts has attracted a great deal of attention in the field of electrocatalysis. The accurate design of the catalysts can avoid an unnecessary process that occurs during the blind trial. Based on the interaction between different metal species, a metallic compound supported by the carbon nanotube was designed. Among these compounds, RhFeP2CX (R-RhFeP2CX-CNT) was found to be in a rich-electron environment at the Fermi level (denoted as a flat Fermi surface), beneficial to the hydrogen evolution reaction (HER). R-RhFeP2CX-CNT exhibits a small overpotential of 15 mV at the current density of 10 mA·cm-2 in acidic media. Moreover, the mass activity of R-RhFeP2CX-CNT is 21597 A·g-1, which also demonstrates the advance of the active sites on R-RhFeP2CX-CNT. Therefore, R-RhFeP2CX-CNT can be an alternative catalyst applied in practical production, and the strategies of a flat Fermi surface will be a reliable strategy for catalyst designing.

Peer Stress Spills Over to Family Stress in the Context of Emotion Regulation Difficulties: A Daily Diary Study with Chinese Adolescents.

Conflict in peer and family relationships becomes more common in the adolescent period when compared to previous developmental periods. These typical developmental challenges can be exacerbated in the context of poor emotion regulation skills. Using daily diary data, the current study examined the stress spillover effects of peer and family stress on one another, as well as the moderating role of emotion regulation challenges (i.e., emotional inhibition, dysregulation). A sample of 310 Chinese adolescents (Mage = 13.02 years, SD = 0.76 years, 50.7% boys) completed an initial measure of emotion regulation difficulties, then reported on peer and family stress for 10 consecutive weekdays. Results indicated that there was an overall same-day peer stress spillover effect in which adolescents' peer stress on a given day was negatively associated with later conflictual interactions with their parents. Further, the relation between peer stress and same- and next-day family stress was exacerbated in the context of high levels of emotional inhibition. Family stress did not significantly relate to next-day peer stress, nor was this association moderated by difficulties with emotion regulation. These results highlight the temporal sequence of daily peer-to-family stress spillover. Though emotional inhibition may be culturally adaptive for maintaining interpersonal harmony, it can be maladaptive in managing stress for Chinese adolescents.

A Simple Organo-Electrocatalysis System for the Chlor-Related Industry.

Consuming a substantial quantum of energy (~165 TW h), the chlor-alkali industry garners considerable scholarly and industrial interest, with the anode reaction involving the oxidation of chloride ions being a paramount determinant of reaction rates. While the dimensionally stable anode (DSA) displays commendable catalytic activity and longevity, they rely on precious metals and exhibit a non-negligible side reaction in sodium hypochlorite (NaClO) production, underscoring the appeal of metal-free alternatives. However, the molecules and systems currently available are characterized by intricate complexity and are not amenable to large-scale production. Herein, we have successfully developed an economical and highly efficient molecular catalyst, demonstrating superior performance compared with the former organic molecules in the chloride ion oxidation process (COP) for the production of both chlorine gas (Cl2) and NaClO. The molecule of 2N only needs 92 mV to reach a current density of 1000 mA cm-2, with a small cost of only 0.002 $ g-1. Furthermore, we propose a novel mechanism underpinned by non-covalent interactions, serving as the foundation for an innovative approach to the design of efficient anodes for the COP.

Organocatalyst Supported by a Single-Atom Support Accelerates both Electrodes used in the Chlor-Alkali Industry via Modification of Non-Covalent Interactions.

Consuming one of the largest amount of electricity, the chlor-alkali industry supplies basic chemicals for society, which mainly consists of two reactions, hydrogen evolution (HER) and chlorine evolution reaction (CER). Till now, the state-of-the-art catalyst applied in this field is still the dimensional stable anode (DSA), which consumes a large amount of noble metal of Ru and Ir. It is thus necessary to develop new types of catalysts. In this study, an organocatalyst anchored on the single-atom support (SAS) is put forward. It exhibits high catalytic efficiency towards both HER and CER with an overpotential of 21 mV and 20 mV at 10 mA cm-2 . With this catalyst on both electrodes, the energy consumption is cut down by 1.2 % compared with the commercial system under industrial conditions. Based on this novel catalyst and the high activity, the mechanism of modifying non-covalent interaction is demonstrated to be reliable for the catalyst's design. This work not only provides efficient catalysts for the chlor-alkali industry but also points out that the SACs can also act as support, providing new twists for the development of SACs and organic molecules in the next step.

Intrinsically Low Thermal Conductivity in a Novel Cu-S Modified ZrS2 Compound with Asymmetric Bonding.

Materials with low thermal conductivity have received significant attention across various research fields, including thermal insulation materials, thermal barrier coatings, and thermoelectric materials. Exploring novel materials with intrinsically low thermal conductivity and investigating their phonon transport properties, chemical bonding, and atomic coordination are crucial. In this study, a novel ternary sulfide is successfully discovered, Cu2 ZrS3 , which is achieved by introducing copper ions into both the interlayer and intralayer of ZrS2 . The resulting structure encompasses various coordination forms within each layer, such as [CuS4 ], [ZrS6 ], and [CuS3 ], leading to pronounced phonon anharmonicity induced by the asymmetric bonding of tri-coordinated Cu atoms within the [ZrS6 ] layer. As a result, Cu2 ZrS3 exhibits intrinsically low lattice thermal conductivity (κL ) of about 0.83 W m-1 K-1 at 300 K and 0.35 W m-1 K-1 at 683 K, which are in the exceptionally low level among sulfides. In comparison to the conventional approach of inserting guests between layers, the substitution of atoms within layers provides a novel and effective strategy for designing low κL materials in transition metal dichalcogenides (TMDCs).

Polarization-independent and reciprocity-unbroken multifunctional device with composite symmetrical structure.

A design method for a dynamically tunable multifunctional device, which is insensitive to polarization while maintaining unbroken reciprocity, is proposed. The device utilizes a multilayer composite symmetrical structure incorporating vanadium dioxide (VO2). This design enables dynamic switching among the functions of linear polarization conversion, filtering, and absorption. In the polarization conversion state, the device achieves orthogonal deflection of incident waves at any polarization angle, with a polarization conversion ratio (PCR) exceeding 95%. When switched to the filtering function, a band-stop filter with a -20 dB bandwidth of 0.56 THz is obtained. In the absorption function, the device exhibits a peak absorption efficiency of up to 99%. Furthermore, the paper discusses the potential for a dual-band device based on the proposed structure. The device maintains reciprocity in all functions and effectively handles incident waves from both positive and negative directions. This adaptability and flexibility make it suitable for various applications, including switches, sensors, and modulators.

Immunogenicity and protective efficacy of a recombinant adenovirus containing the fusion protein of bovine parainfluenza virus type 3 genotype C in mice.

Bovine parainfluenza virus type 3 (BPIV3) is a viral respiratory pathogen of cattle that causes substantial economic losses. A replicating-defective recombinant human adenovirus type 5 (HAd5), carrying a fusion protein of BPIV3 genotype C (HAd5-F), was constructed and evaluated for its immunogenicity and protective efficacy in mice. After intramuscular injection with the HAd5-F, the IgG titers against F proteins increased to 1:102,400, and virus-neutralizing titers increased to 1:256, significantly higher than those in the group injected with inactivated BPIV3C in mice (p<0.05). The splenic CD4+/CD8+T lymphocytes and IFN-γ+/IL-4+ cytokine percentages were more significant in the HAd5-F group than those in the control group. A BPIV3C challenge in a mouse model was used to assess protective efficacy of the HAd5-F. The viral loads in the lungs and tracheas of mice immunized with the HAd5-F were significantly lower than those in the control group (p<0.0001). There were no significant histopathological alterations in the lungs of mice vaccinated with the HAd5-F. These findings suggested that the HAd5-F elicited excellent immunity against BPIV3C infection.

Association between fibrinogen-to-albumin ratio and prognosis of patients with heart failure.

BACKGROUND: Systemic inflammation is closely associated with the development and progression of heart failure (HF), increasing vulnerability to thromboembolic events. This retrospective cohort study assessed the potential of the fibrinogen-to-albumin ratio (FAR), a new inflammatory biomarker, as a prognostic indicator for HF risk. METHODS: One thousand one hundred and sixty six women and 826 men with a mean age of 70.70 ± 13.98 years were extracted from the Medical Information Mart for Intensive Care-IV (MIMIC-IV v2.0) database. Additionally, a second cohort was obtained, including 309 patients from the Second Affiliated Hospital of Wenzhou Medical University. The relationship between FAR and the prognosis of HF was evaluated using multivariate analysis, propensity score-matched analysis, and subgroup analysis. RESULTS: Fibrinogen-to-albumin ratio was an independent risk factor for 90-day all-cause mortality (hazard ratio: 1.19; 95% confidence interval (CI): 1.01-1.40), 1-year all-cause mortality (hazard ratio: 1.23; 95% confidence interval: 1.06-1.41), and length of hospital stay (LOS) (ß: 1.52; 95% CI: 0.67-2.37) in the MIMIC-IV dataset, even after adjusting for potential covariates. These findings were verified in the second cohort (ß: 1.82; 95% CI: 0.33-3.31) and persisted after propensity score-matching and subgroup analysis. FAR was positively correlated with C-reactive protein, NT-proBNP, and Padua score. The correlation between FAR and NT-proBNP (R = .3026) was higher than with fibrinogen (R = .2576), albumin (R = -.1822), platelet-to-albumin ratio (R = .1170), and platelet-to-lymphocyte ratio (R = .1878) (ps < .05). CONCLUSIONS: Fibrinogen-to-albumin ratio is an independent risk prognostic factor for 90-day, 1-year all-cause mortality and LOS among HF patients. Inflammation and prothrombotic state may underlie the relationship between FAR and poor prognosis in HF.

Transcriptomic analysis following polystyrene nanoplastic stress in the Pacific white shrimp, Litopenaeus vannamei.

Plastics are widely produced for industrial and domestic applications due to their unique properties, and studies on the toxic effects of nanoplastics (NPs) on aquatic animals are essential. In this study, we investigated the transcriptomic patterns of Litopenaeus vannamei after NPs exposure. We found that the lysosome pathway was activated when after NPs exposure, with up-regulated DEGs, including glucocerebrosidase (GBA), hexosaminidase A (HEXA), sphingomyelin phosphodiesterase-1 (SMPD1), and solute carrier family 17 member 5 (SLC17A5). In addition, the PI3K-Akt signaling pathway was strongly affected by NPs, and the upstream genes of PI3K-Akt, including epidermal growth factor receptor (EGFR), integrin subunit beta 1 (ITGB1) and heat shock protein 90 (HSP90) were up-regulation. Other genes involved in lipogenesis, such as sterol regulatory element binding transcription factor 1 (SREBP-1c), fatty acid synthase (FASN) and stearoyl-CoA desaturase (SCD-1), were down-regulated. However, the contents of triglycerides (TG) and total cholesterol (TCH) in L. vanname hepatopancreas were reduced, which indicated that the ingestion of NPs led to the disturbance of hepatic lipid metabolism. What more, NPs treatment of L. vannamei also caused oxidative stress. In addition, NPs can damage part of the tissue structure and affect the physiological function of shrimps. The results of this study provide valuable ecotoxicological data to improve the understanding of the biological fate and effects of nanoplastics in L. vannamei.

Metal-free recycling of waste polyethylene terephthalate mediated by TBD protic ionic salts: the crucial role of anionic ligands.

The structure-activity relationships of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) based protic ionic salts for polyethylene terephthalate (PET) glycolysis by ethylene glycol (EG) were comprehensively investigated through theoretical prediction and experimental verification. The proton capture ability of the anionic ligand from EG is positively correlated with the activity of the catalyst, as the generation of EG- was crucial for the chain breaking reaction via nucleophilic attack on the carbonyl group. Furthermore, density functional theory calculations demonstrated that the HTBD cation and anionic ligands work in a cooperative manner in the PET glycolysis reaction, where the ligands abstract a proton from EG to generate EG- and provide a proton to produce the bis(hydroxyalkyl)terephthalate (BHET) product. The rate-determining step is the nucleophilic attack step, where the Gibbs energy barriers (ΔG≠) increase in the order of 29.7 kcal mol-1 (HTBD-OAc) < 30.2 kcal mol-1 (HTBD-CH3CH2COO) < 31.4 kcal mol-1 (HTBD-HCOO) < 35.7 kcal mol-1 (HTBD-CH3COCOO) < 36.9 kcal mol-1 (HTBD-NO3). This is confirmed from the experimental results that the BHET yields decrease in the order of 84.8% (HTBD-OAc) > 82.4% (HTBD-CH3CH2COO) > 80.2% (HTBD-HCOO) > 73.6% (HTBD-CH3COCOO) > 4.7% (HTBD-NO3). These findings offer valuable guidance for designing more efficient metal-free protic ionic salts, promoting sustainable PET recycling.

Preparation of a novel metal-free polypyrrole-red phosphorus adsorbent for efficient removal of Cr(VI) from aqueous solution.

The toxicity and carcinogenicity of Cr(VI) makes it a major threat to the health of animals and people. However, how to efficiently remove Cr(VI) still faces important challenges. In this study, a new metal-free polypyrrole-red phosphorus (PPy-RP) composite is successfully synthesized by in-situ oxidation polymerization for Cr(VI) removal from wastewater. The maximum adsorption capacity (qm) of Cr(VI) on PPy-RP-1 is 513.2 mg/g when the pH value is 2, which is far superior to RP nanosheets (207.8 mg/g) and PPy (294.9 mg/g). The improved qm can be ascribe to the good dispersion and increased specific surface area of PPy-RP adsorbent. Encouragingly, PPy-RP adsorbent still exhibits excellent stability after 7 cycles tests without a significant decline in removal efficiency, and remain above 81.4%. Based on the fittings of adsorption isotherms and kinetics, the process conforms to the pseudo-first-order kinetic model and the single-layer adsorption of the Langmuir model with an R2 value of 0.98533. The adsorption process is chemical and monolayer. The experimental result demonstrates that the PPy-RP can efficient removal Cr(VI) by electrostatic attraction and complexation reaction (formation of N-Cr(VI) bond) through the PPy on the surface. The results of this study indicate that PPy-RP is a promising adsorbent to remove the Cr(IV).

3,4-benzopyrene aggravates myocardial ischemia-reperfusion injury-induced pyroptosis through inhibition of autophagy-dependent NLRP3 degradation.

Polycyclic aromatic hydrocarbons (PAHs) are produced during combustion of organic matter, such as during cigarette smoking, and they exist widely in the environment. Exposure to 3,4-benzo[a]pyrene (BaP), as the most widely studied PAHs, relates to many cardiovascular diseases. However, the underlying mechanism of its involvement remains largely unclear. In this study, we developed a myocardial ischemia-reperfusion (I/R) injury mouse model and an oxygen and glucose deprivation-reoxygenation H9C2 cell model to evaluate the effect of BaP in I/R injury. After BaP exposure, the expression of autophagy-related proteins, the abundance of NLRP3 inflammasomes, and the degree of pyroptosis were measured. Our results show that BaP aggravates myocardial pyroptosis in a autophagy-dependent manner. In addition, we found that BaP activates the p53-BNIP3 pathway via the aryl hydrocarbon receptor to decrease autophagosome clearance. Our findings present new insights into the mechanisms underlying cardiotoxicity and reveal that the p53-BNIP3 pathway, which is involved in autophagy regulation, is a potential therapeutic target for BaP-induced myocardial I/R injury. Because PAHs are omnipresent in daily life, the toxic effects of these harmful substances should not be underestimated.

Facile synthesis of NiAl2O4/g-C3N4 composite for efficient photocatalytic degradation of tetracycline.

Designing high-efficiency photocatalysts responsive to visible light is important for the degradation of antibiotics in water. Heterojunction engineering is undoubtedly an effective strategy to improve the photocatalytic performance. In this work, spinel-type metal oxides (NiAl2O4, NAO) are synthesized by a simple sol-gel and calcination process. After compounding graphitic carbon nitride (g-C3N4), NAO/g-C3N4 heterojunction is obtained, which then is used as the photocatalyst for tetracycline hydrochloride (TC). The effects of photocatalyst dosage, the initial concentration of TC, and solution pH on photodegradation performance are systematically studied. The removal rate of TC on NAO/g-C3N4 reach up to ∼90% after visible light irradiation for 2 hr and the degradation rate constant is ∼7 times, and ∼32 times higher than that of pure NAO and g-C3N4. The significantly improved photocatalytic activity can be attributed to the synergistic effect between well matched energy levels in NAO/g-C3N4 heterojunctions, improvement of interfacial charge transfer, and enhancement of visible light absorption. This study provides a way for the synthesis of efficient photocatalysts and an economic strategy for removing antibiotics contamination in water.

Effects of berberine hydrochloride on immune response in the crab Charybdis japonica.

Berberine hydrochloride is the main effective component of Coptis spp. used in Chinese herbal medicine and its underlying molecular mechanisms, responsible for inducing effects in crustacean species, are not fully understood. In this study, the molecular response of the crab Charybdis japonica to berberine hydrochloride exposure was studied using transcriptome sequencing. The survival rate, gene expression and activities of several immune enzymes were measured after berberine hydrochloride treatments, with or without injection of the pathogenic bacterium Aeromonas hydrophila. A total of 962 differentially expressed genes (464 up-regulated and 498 down-regulated) were observed during exposure to 100 mg/L of berberine hydrochloride and in the control group after 48 h. Enrichment analysis revealed that these genes are involved in metabolism, cellular processes, signal transduction and immune functions, indicating that exposure to berberine hydrochloride activated the immune complement system. This bioactive compound simultaneously activated fibrinogen beta (FGB), fibrinogen alpha (FGA), alpha-2-macroglobulin (A2M), kininogen (KNG), fibrinogen gamma chain (FGB), alpha-2-HS-glycoprotein (AHSG), caspase-8 (CASP8), cathepsin L (CTSL), adenylate cyclase 3 (Adcy3) and MMP1. Its action could significantly increase the survival rate of the crabs injected with A. hydrophila and promote the activity of LZM, Caspas8, FGA, ACP and AKP in the hepatopancreas. When A. hydrophila was added, the neutralization of 300 mg/L berberine hydrochloride maximized the activities of Caspas8, LZM, ACP and AKP. Our results provide a new understanding of the potential effects of berberine hydrochloride on the immune system mechanisms in crustaceans.

Simulating electrical fields in the orbital angular momentum space of light.

We study a system of coupled degenerate cavities with a switchable beam rotator embedded in the optical path of the main cavity. By exploiting the phase shift of the beam rotator dependent on the orbital angular momentum of the optical modes, and modulating the phase imbalance in the auxiliary cavity, it is shown that the system dynamics is equivalent to that of a charged particle in a 1D lattice subject to both static and time-dependent electrical fields. We investigate interesting physics and phenomena such as Bloch oscillations that arise due to the simulated electrical fields, and discuss how they can be used for practical purposes such as storing optical signals in a quantum memory. We also present a powerful measurement scheme to detect the system dynamics that is non-intrusive and technically easy to perform.

Enhanced Thermoelectric Performance in Ge0.955- x Sbx Te/FeGe2 Composites Enabled by Hierarchical Defects.

Manipulations of carrier and phonon scatterings through hierarchical structures have been proved to be effective in improving thermoelectric performance. Previous efforts in GeTe-based materials mainly focus on simultaneously optimizing the carrier concentration and band structure. In this work, a synergistic strategy to tailor thermal and electrical transport properties of GeTe by combination with the scattering effects from both Ge vacancies and other defects is reported. The addition of Fe in GeTe-based compounds introduces the secondary phase of FeGe2 , synchronously increasing the concentration of Ge vacancies and arousing more Ge planar defects. These hierarchical defects contribute to a large scattering factor, leading to a significant enhancement of Seebeck coefficient and further a splendid power factor. Meanwhile, benefiting from the reinforced phonon scatterings by multiscale hierarchical structures, an extremely low lattice thermal conductivity is successfully achieved. With simultaneously optimized electrical and thermal transport properties, a maximum figure of merit, zT, value of 2.1 at 750 K and an average zT value of 1.5 in 400-800 K are realized in Ge0.875 Sb0.08 Te/1.5%FeGe2 . This work demonstrates that manipulation of hierarchical defects is an effective strategy to optimize the thermoelectric properties.

Total Synthesis of Chalaniline B: An Antibiotic Aminoxanthone from Vorinostat-Treated Fungus Chalara sp. 6661.

Chalaniline B [1-anilino-2,8-dihydroxy-3-(hydroxymethyl)xanthone], an antibiotic previously isolated from vorinostat-treated Chalara sp., was prepared in 7 steps from 2-hydroxyxanthone by a route incorporating regioselective oxidative transformations (bromination at C1/C3, ketone directed Pd(II)-catalyzed hydroxylation at C8), installation of the C1-anilino moiety by a regioselective Buchwald-Hartwig amination reaction from 1,3-dibromo-2,8-dimethoxyxanthone, and late-stage hydroxymethylation at C3 using a Stille cross-coupling. Biological evaluation of deshydroxymethylchalaniline B (1-anilino-2,8-dihydroxyxanthone) revealed MIC values of 8 µg mL-1 (25 µM) against both methicillin resistant S. aureus and B. subtilis.