2-furancarboxylic Acid Research Articles

Four Tremulanes and Two Pyroglutamate-Containing Dipeptides from the Mangrove Endophytic Fungus Phaeosphaeriopsis sp. P11.

Four new tremulane sesquiterpenes, named phaeosphaerienols A-D (1-4), and two new pyroglutamate-containing dipeptides, named phaeosphaeratides A-B (5-6), were isolated from the mangrove endophytic fungus Phaeosphaeriopsis sp. P11, together with a new 2-furancarboxylic acid derivative (7). Structurally, pheaosphaerienols A-C (1-3) are rare tremulanes containing a 1,10-epoxide moiety. The structures of these compounds were established by extensive NMR spectroscopic data, single-crystal X-ray diffraction analysis, and Marfey's derivatization method. All the isolates were evaluated for their cytotoxic, antibacterial, and DPPH free radical scavenging effects. However, none of the compounds exhibited obvious activities.

Photocatalytic oxidation of benzylamines and sulfides using selected organoboron complexes as molecular oxygen activators

In this work a synthetic protocol was developed to obtain a series of diarylborinic complexes bearing a diarylboron moiety chelated with various bidentate N,O-ligands derived from 5-chloro-8-hydroxy-7-iodoquinoline, quinoline-2,4-dicarboxylic acid or 2-(2-hydroxy-5-methylphenyl)benzotriazole. The obtained complexes were characterized by NMR, IR, CV, UV–vis and single-crystal X–ray diffraction analyses. The experimental data were supported by theoretical calculations. The obtained complexes were tested as singlet oxygen sensitizers for the oxidation of 2-furancarboxylic acid, oxidative coupling of benzylamines and oxidation of sulfides. Among the studied compounds, the diarylborinic derivative bearing a 5-chloro-8-oxy-7-iodoquinolinate ligand was selected as the most economic singlet oxygen sensitizer. However, the diphenylborinic complex bearing an 8-oxyquinolinate ligand was the most efficient for the selective oxidation of various benzylamines to their respective N-benzylidene benzylamines.

Synthesis of vinyl esters of some furan carboxylic acids based on vinyl acetate

Investigation of synthesized vinyl esters of several furancarboxylic acids: 2-furancarboxylic, 3-furancarboxylic, 5-formyl-2- furancarboxylic, 5-nitro-2-furanoic and 2,5-furandicarboxylic from vinyl acetate using the reaction vinyl substitution in the presence of the system: 2- chloro-4,6-dimethoxy-1,3,5-triazine, as well as Zn(OTf)2, 3,3’-Ph2BINOL- 2Li, KOtrBu and BuLi has been carried out. At the same time increasing of the catalytic activity of these systems was identified as following: 3,3’- Ph2BINOL-2Li < BuLi < KOtrBu < Zn(OTf)2. The influence of various factors on products yield was studied. Optimal conditions for the formation of vinyl esters of carboxylic acids were: temperature -30°C, the Zn(OTf)2 system, the molar ratio of carboxylic acid and vinyl acetate is 1:1.2. The yields of vinyl esters of the studied furancarboxylic acids has increased in the following order: vinyl ester of 5-nitro-2-furancarboxylic acid < vinyl ester of 5-formyl-2-furancarboxylic acid < vinyl ester of 2-furancarboxylic acid < vinyl ester of 3-furancarboxylic acid < vinyl ester 2 ,5- furandicarboxylic acid. The structure of the synthesized compounds was confirmed by IR, 1H, 13C spectroscopy and gas chromatography-mass spectrometry.

Mild Hydrogenation of 2-Furoic Acid by Pt Nanoparticles Dispersed in a Hierarchical ZSM-5 Zeolite.

Hydrogenation of biobased compounds can add value to platform molecules obtained from biomass refining. Herein, we explore the hydrogenation of 2-furoic acid (2-furancarboxylic acid, FCA), a derivative of furfural, with H2 generated in situ by NaBH4 hydrolysis at ambient conditions. Nearly complete conversion of FCA was obtained with tetrahydrofuroic acid (THFA) and 5-hydroxyvaleric acid (5-HVA) as the only two reaction products over Pt nanoparticles supported on hierarchical ZSM-5. Small Pt nanoparticles (2 to 3 nm) were stabilized by ZSM-5 nanosheets. At an optimized Pt loading, the Pt nanoparticles can catalyze the hydrolysis of NaBH4 and the subsequent hydrogenation of FCA with the assistance of Brønsted acid sites. Nanostructuring ZSM-5 into nanosheets and its acidity contributes to the stability of the dispersed Pt nanoparticles. Deactivation due to NaBO2 deposition on the Pt particles can be countered by a simple washing treatment. Overall, this approach shows the promise of mild hydrogenation of biobased feedstock coupled with NaBH4 hydrolysis.

Enhanced production of anteiso-branched chain fatty acids rich bacterial oil using Lentibacillus salarius strain BPIITR under furan aldehydes induced oxidative stress

Monomethyl branched-chain fatty acids (mBCFAs) are highly valuable compounds in the oleochemical industry, with diverse industrial applications including pharmaceuticals, biofuels and lubricants. In the current study, the medium components of L. salarius BPIITR were statistically optimized to produce mBCFAs-rich lipid, yielding up to 227.16 ± 16.2 mg/g dcw. The supplementation of 2-methyl butyric acid increased the lipid content to 276.42 ± 7.46 mg/g dcw, with anteiso fatty acids up to 87.59 ± 1.56 % w/w of the total lipid. The addition of 5-hydroxymethyl furfural (5-HmF) and furfural induced oxidative stress, resulting in the synthesis of lipids rich in anteiso-mBCFAs. Furfural supplementation led to a lipid accumulation of 256.49 ± 7.91 mg/g dcw, whereas with 5-HmF, it increased to 284.75 ± 8.98 mg/g dcw. Furthermore, the elongation of mBCFAs from C15:0 to C17:0 was significantly affected during oxidative stress. This study suggests that under oxidative stress conditions, the synthesis of anteiso fatty acids is favored over iso-fatty acids in L. salarius BPIITR. Additionally, value-added products such as trehalose and furan carboxylic acids were identified as potential co-products in this study, with trehalose reaching up to 255.84 ± 8.04, 163.65 ± 20.94, and 217.46 mg/g dcw in the presence of 2-methylbutyric acid, furfural, and 5-HmF, respectively. The concentration of 2-furan carboxylic acid and 2,5-furan dicarboxylic acids in the fermentation broth reached up to 4.37 ± 0.28 g/L and 2.48 ± 0.35 g/L, respectively. The utilization of short-chain fatty acids and furan aldehydes not only provided a cost-effective carbon source but also modulated the metabolic flux towards specific mBCFAs rich bacterial oil production.

Alkylation of furancarboxylic acid derivatives with alkenes catalyzed by nickel complexes with N-heterocyclic carbenes

Alkylation of furancarboxylic acid derivatives with alkenes catalyzed by nickel complexes with N-heterocyclic carbenes

Selective two-electron electrocatalytic conversion of 5-Hydroxymethylfurfural boosting hydrogen production under neutral condition over Co(OH)2-CeO2 catalyst

The coupling of electrocatalytic oxidation of biomass derivatives with hydrogen evolution reaction (HER) is a promising strategy to promote hydrogen production, but it is extremely challenging to control the mild electrocatalytic conversion of biomass to high value-added chemicals simultaneously. A Co(OH)2-CeO2 self-supported catalyst is constructed and used as anode for selective electrocatalytic conversion of biomass derivative 5-hydroxymethylfurfural (HMF) coupled with HER in two-chamber electrolysis system. The adjusting of pH and potential regulates the oxidation ability of hydroxyl and aldehyde groups, achieving selective two-electron electrocatalytic conversion of HMF to 2-furancarboxylic acid (HMFCA) with a selectivity of 89.4%. In situ Raman spectroscopy reveals that the evolution of Co multivalent active species at different electrolysis conditions is key to the selective oxidation of HMF. In addition, the hydrogen production coupled with selective electrocatalytic conversion of HMF is 4.1 times that of the water splitting system, revealing its potential in developing clean energy.

Efficient Oxidation of Furfural to Furancarboxylic Acid over CuO‐MnCO3 Catalyst

AbstractIt is of great significance to efficiently produce furancarboxylic acid (FA) by furfural oxidation at room temperature. Here in, based on an available CuO‐MnCO3 bimetallic catalyst, an efficient and sustainable heterogeneous catalyst system in sodium hypochlorite solution was designed to be served for the selective oxidation of furfural to FA. Interestingly, Cu6‐Mn4 showed 100 % furfural conversion and quantitative selectivity to FA (96.9 %). Especially, we demonstrate the CuO exhibited main catalytic performance in this experiment. In particular, the introduction of MnCO3 into Cu‐Mn catalyst resulted in an increase reactivity of the lattice oxygen in the catalyst. More importantly, Cu6‐Mn4 also showed excellent stability in reusability test. This study provides a simple and rapid catalytic strategy and scientific basis for the development of an efficient and mild aerobic oxidation of furfural.

Honeycomb 3D Coordination Barium Polymer with 2-Furancarboxylic Acid Anions: Effect of Thermal Stability

Honeycomb 3D Coordination Barium Polymer with 2-Furancarboxylic Acid Anions: Effect of Thermal Stability

GC–MS screening of the phytochemical composition of Ziziphus honey: ADME properties and in vitro/in silico study of its antimicrobial activity

A revival interest has been given to natural products as sources of phytocompounds to be used as alternative treatment against infectious diseases. In this context, we aimed to investigate the antimicrobial potential of Ziziphus honey (ZH) against twelve clinical bacterial strains and several yeasts and molds using in vitro and computational approaches. The well-diffusion assay revealed that ZH was able to induce growth inhibition of most Gram-positive and Gram-negative bacteria. The high mean growth inhibition zone (mGIZ) was recorded in E. coli (Clinical strain, 217), S. aureus followed by E. coli ATCC 10536 (mGIZ values: 41.00 ± 1 mm, 40.67 ± 0.57 mm, and 34.67 ± 0.57 mm, respectively). The minimal bactericidal concentrations (MBCs) and minimal fungicidal concentration values (MFCs) from approximately 266.33 mg/mL to over 532.65 mg/mL. Molecular docking results revealed that the identified compounds maltose, 2-furoic acid, isopropyl ester, 2,4-imidazolidinedione, 5-(2-methylpropyl)-(S)- and 3,4,5-trihydroxytoluene, S-Methyl-L-Cysteine, 2-Furancarboxylic acid, L-Valine-N-ethoxycarbonyl, Hexanoic acid, 3,5,5-trimethyl-, Methyl-beta-D-thiogalactoside, gamma-Sitosterol, d-Mannose, 4-O-Methylmannose, 2,4-Imidazolidinedione, 5-(2-methylpropyl)- (S) were found to have good affinity for targeted receptor, respectively. Through a 100-ns dynamic simulation research, binding interactions and stability between promising phytochemicals and the active residues of the studied enzymes were confirmed. The ADMET profiling of all identified compounds revealed that most of them could be qualified as biologically active with good absorption and permeation. Overall, the results highlighted the efficiency of ZH against the tested clinical pathogenic strains. The antimicrobial potential and the potency displayed by the identified compounds could imply their further pharmacological applications. Communicated by Ramaswamy H. Sarma

Herbivore induced fruit volatiles guide the solitary tephritid endoparasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae) in selecting an oviposition substrate.

Oviposition in a generalist parasitoid is a complex process that involves interactions among its host, host plant, and spatiotemporal environment. Our study was aimed at exploring the ability of a generalist parasitic wasp, Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae), in perceiving odor cues from its host insect [Oriental fruit fly Bactrocera dorsalis (Hendel, Diptera: Tephritidae)] in infested mango fruits. A series of experiments involving behavioral and electrophysiological studies suggest that D. longicaudata is able to distinguish host infested fruit volatiles from uninfested. Additionally, we found that D. longicaudata can distinguish between high and low-level infestations using specific cues emanating from fruits. Coupled gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS) analysis of infested mango fruit head space volatiles identified compounds such as ethyl butanoate, ethyl 3-hydroxybutyrate, β-myrcene, trans-β-ocimene, allo-ocimene, ethyl octanoate, ethyl-α-toulate, β-elemene, β-caryophyllene, humulene, caryophyllene oxide, ethyl dodecanoate, ethyl hexadecanoate, 2-furancarboxylic acid, 3-hydroxy-2-methyl-4-pyrone, and phenethyl alcohol emanated from three different host treatments with different levels of larval infestation which elicited antennal responses in D. longicaudata. We suggest that these cues might play a significant role in attracting D. longicaudata in the field.

Microbispofurans A-C, plant growth-promoting furancarboxylic acids from plant root-derived Microbispora sp.

Microbispofurans A-C (1-3), new alkyl/alkenyl furancarboxylic acids, were isolated from the culture extract of the plant root-derived Microbispora sp. RD004716. The planar structures of 1-3 were determined by extensive analysis of 1D and 2D NMR spectroscopic data. Although 1-3 showed no appreciable antimicrobial activity or cytotoxicity, strong plant growth-promotion activity of the germinated red leaf lettuce seeds was observed at 10 μM. Furancarboxylic acids and their methyl esters were found in actinomycetes and fungi; however, the isolation of furandicarboxylic acid was unprecedented.

Peniandranoids A-E: Meroterpenoids with Antiviral and Immunosuppressive Activity from a Penicillium sp.

Peniandranoids A-E (1-5), five new meroterpenoids, together with three known analogues (6-8), were isolated from the fermentation of a soil-derived fungus, Penicillium sp.sb62. Their structures including absolute configurations were determined by extensive spectroscopic analysis, and the absolute configurations of compounds 1 and 5 were further elucidated by single-crystal X-ray diffraction. Peniandranoids A-E belong to a rare class of andrastin-type meroterpenoids incorporating an extra polyketide unit (a C10 polyketide unit for 1 and 2, a C9 polyketide unit for 3 and 4, and a furancarboxylic acid unit for 5). Compounds 1 and 6 exhibited favorable inhibitory activities against influenza virus A (H1N1) with EC50 values of 19 and 14 μg/mL, respectively. Compounds 3-8 exhibited potent immunosuppressive activities against concanavalin A-induced T cell proliferation with EC50 values ranging from 4.3 to 27 μM and lipopolysaccharide-induced B cell proliferation with EC50 values ranging from 7.5 to 23 μM, respectively.

Insight into the noble-metal-free NiCoAl catalyst boosting the reductive esterification of furancarboxylic acid to methyl 2-tetrahydrofuroate

Reduction of high oxidation level furancarboxylic acid (FA) with the retention of the carboxyl group is particularly important for the utilization, however, it has been rarely explored over non-precious catalysts and is challenging. Here, we demonstrate an excellent noble-metal-free trimetallic NiCoAl catalyst for the reductive esterification of FA to methyl 2-tetrahydrofuroate (MeTHFC), which delivers the complete conversion of FA and MeTHFC yield of up to 99%. More importantly, Ni0.5Co0.5Al could offer YMeTHFC > 90% over five reusability cycles. Detailed investigations suggest that the high activity originates from the synergistic of Ni-Co alloys sites and acid sites in Ni0.5Co0.5Al. The Ni-Co alloy sites were mainly responsible for the adsorption and dissociation of H2, which in turn improved hydrogenation activity, while the acid sites facilitated the esterification of FA and the adsorption and further activation of the furan ring. This work provides an eco-friendly noble-metal-free catalyst to enrich the strategies for the reductive esterification process.

Base-Free Aerobic Oxidation of Furfuralcohols and Furfurals to Furancarboxylic Acids over Nitrogen-Doped Carbon-Supported AuPd Bowl-Like Catalyst.

Upgrading furfuralcohols and furfurals to furancarboxylic acids is of great significance for high value-added downstream chemicals synthesis and biomass conversion. Developing an efficient catalyst is the key to acquiring a completely sustainable process. Herein, nitrogen-doped carbon-supported bimetallic AuPd bowl-like catalysts were synthesized. The surface wettability of nitrogen-doped carbon was well adjusted by the nitrification process. Benefiting from the alloying effect of bimetallic AuPd catalyst and the formation of hydroxyl radical initiated by H2 O dissociation on the hydrophilic surface of nitrated nitrogen-doped carbon, base-free aerobic oxidation of 5-hydroxymethylfurfural (HMF) could produce the highest 2,5-furandicarboxylic acid (FDCA) yield of 93.9 %. In-situ infrared spectroscopy uncovered adsorption configuration of HMF, and the nitrated carbon surface was favorable for HMF and intermediates to enter the active sites, greatly promoting the catalytic oxidation process. Employing other furfuralcohols (furfuryl alcohol, furan-2,5-diyldimethanol, 2,5-bishydroxymethylfuran) as well as furfural and 5-methylfurfural as starting materials, 35.6-95.4 % yield of furancarboxylic acids (FDCA, 2-furoic acid, 5-methyl-2-furoic acid) were also obtained. Moreover, the developed catalysts could maintain excellent stability and activity after four successive runs. This deep insight into the role of bimetallic synergy and surface wettability provides a basis for the rational design of the highly efficient catalysts for the oxidation of furfuralcohols and furfurals and related reactions.

Heterogeneously-catalyzed aerobic oxidation of furfural to furancarboxylic acid with CuO-Promoted MnO2

A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn–Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid (FA). Interestingly, Mn2Cu1Ox exhibited an excellent furfural conversion of 99% with quantitative selectivity toward FA. Especially, we demonstrate the significant weakening of the Mn–O bonds with the incorporation of CuO into the Mn–Cu oxides, resulting in an improved OL reactivity of Mn2Cu1Ox, which brings about a higher catalytic activity for furfural oxidation. More importantly, Mn2Cu1Ox could exhibit YFA>90% over 5 cycles of reusability test. Through this study, the relationship between the morphology, surface chemistry, and catalytic activity of Mn–Cu bimetallic oxides are elucidated, providing a simple and environmentally friendly catalytic strategy and scientific basis for the development of Mn–Cu bimetallic oxides bioderived molecular aerobic oxidation materials.

Oxidation of 5-hydroxymethylfurfural with a novel aryl alcohol oxidase from Mycobacterium sp. MS1601.

SummaryBio‐based 5‐hydroxymethylfurfural (HMF) serves as an important platform for several chemicals, among which 2,5‐furan dicarboxylic acid (FDCA) has attracted considerable interest as a monomer for the production of polyethylene furanoate (PEF), a potential alternative for fossil‐based polyethylene terephthalate (PET). This study is based on the HMF oxidizing activity shown by Mycobacterium sp. MS 1601 cells and investigation of the enzyme catalysing the oxidation. The Mycobacterium whole cells oxidized the HMF to FDCA (60% yield) and hydroxymethyl furan carboxylic acid (HMFCA). A gene encoding a novel bacterial aryl alcohol oxidase, hereinafter MycspAAO, was identified in the genome and was cloned and expressed in Escherichia coli Bl21 (DE3). The purified MycspAAO displayed activity against several alcohols and aldehydes; 3,5 dimethoxy benzyl alcohol (veratryl alcohol) was the best substrate among those tested followed by HMF. 5‐Hydroxymethylfurfural was converted to 5‐formyl‐2‐furoic acid (FFCA) via diformyl furan (DFF) with optimal activity at pH 8 and 30–40°C. FDCA formation was observed during long reaction time with low HMF concentration. Mutagenesis of several amino acids shaping the active site and evaluation of the variants showed Y444F to have around 3‐fold higher kcat/Km and ~1.7‐fold lower Km with HMF.

Insight into the catalytic mechanism of core–shell structured Ni/Ni-N/CN catalyst towards the oxidation of furfural to furancarboxylic acid

Developing low-cost and sustainable non-noble-metal catalysts for the efficient oxidation conversion of biomass-derived furfural to high value-added chemicals has evoked considerable interest. In this contribution, we report a facile and green core–shell structure N-doped carbon-supported nickel catalyst (Ni/Ni-N/CN), which exhibits excellent activity for the oxidation of furfural and other investigated aldehydes to corresponding carboxylic acid. Based on experimental studies, the synergy of Ni and Ni-N species in Ni/Ni-N-CN boosted the outstanding catalytic efficiency. The Ni site in Ni/Ni-N-CN contributes to the adsorption and activation of the aldehyde group in furfural, while the Ni-N site provides a stronger electron transfer ability and basicity of the Ni/Ni-N/CN catalyst, thus facilitates the activation of oxygen and abstraction of hydrogen during furfural oxidation process. Remarkably, Ni/Ni-N/CN-5 offered an outstanding FA formation rate of 4.13 molFA·molNi−1·h−1, which was far more than that of the ever-reported non-noble catalysts. More importantly, the as-prepared Ni/Ni-N/CN catalyst also presents great stability and reusability. The present work provides an efficient catalytic strategy toward selective oxidation reactions.

Insight into the Noble-Metal-Free Nicoal Catalyst Boosting the Reductive Esterification of Furancarboxylic Acid to Methyl 2-Tetrahydrofuroate

Insight into the Noble-Metal-Free Nicoal Catalyst Boosting the Reductive Esterification of Furancarboxylic Acid to Methyl 2-Tetrahydrofuroate

Binuclear Complexes of Cu(II) and Mg(II) with 2-Furancarboxylic Acid: Synthesis, Structure, EPR Spectroscopy, and Results of In Vitro Biological Activity against Mycolicibacterium Smegmatis and SCOV3

Binuclear Complexes of Cu(II) and Mg(II) with 2-Furancarboxylic Acid: Synthesis, Structure, EPR Spectroscopy, and Results of In Vitro Biological Activity against Mycolicibacterium Smegmatis and SCOV3