Organic Analogues Research Articles

Evaluating the inhibitory activity of ferrocenyl Schiff bases derivatives on 5-lipoxygenase: Computational and biological studies

In the search for new 5-LOX inhibitors, two ferrocenyl Schiff base complexes functionalized with catechol ((ƞ5-(E)-C5H4-NCH-3,4-benzodiol)Fe(ƞ5-C5H5) (3a)) and vanillin ((ƞ5-(E)-C5H4-NCH-3-methoxy-4-phenol)Fe(ƞ5-C5H5) (3b)) were obtained. Complexes 3a and 3b were biologically evaluated as 5-LOX inhibitors showed potent inhibition compared to their organic analogs (2a and 2b) and known commercial inhibitors, with IC50 = 0.17 ± 0.05 μM for (3a) and 0.73 ± 0.06 μM for (3b) demonstrated a highly inhibitory and potent effect against 5-LOX due to the incorporation of the ferrocenyl fragment. Molecular dynamic studies showed a preferential orientation of the ferrocenyl fragment toward the non-heme iron of 5-LOX, which, together with electrochemical and in-vitro studies, allowed us to propose a competitive redox deactivation mechanism mediated by water, where Fe(III)-enzyme can be reduced by the ferrocenyl fragment. An Epa/IC50 relationship was observed, and the stability of the Schiff bases was evaluated by SWV in the biological medium, observing that the hydrolysis does not affect the high potency of the complexes, making them interesting alternatives for pharmacological applications.

John David Hunt. 12 December 1936—8 December 2012

John Hunt was a scholar of the solidification of metallic alloys, and published seminal works that are of influence today in the design of alloy casting, welding and additive manufacturing processes. John was raised in the West Country of England, and following school did National Service in the Royal Air Force. He entered the University of Cambridge in 1957, being awarded an honours BA in metallurgy in 1960, and a PhD for studies of solidification of eutectic alloys in 1963. John met Ann Carroll during his Cambridge studies; they married in 1961 and later had three children. From 1963 to 1965 John carried out research with Ken Jackson at Bell Laboratories, New Jersey, USA. They published groundbreaking papers on solidification and pioneered the use of transparent organic analogues. John returned to England and, following a year working at the UK Atomic Energy Authority at Harwell, he joined the faculty at the University of Oxford in 1966. During a 36-year academic career at Oxford, John made significant contributions to the scientific understanding of solidification on many topics, including dendritic array growth, eutectic and peritectic solidification, the columnar-to-equiaxed transition and twin roll casting. As well as being a talented experimentalist, he published many groundbreaking theoretical analyses and also pioneered the use of numerical methods for the simulation of solidification phenomena. He was an accomplished educator of undergraduate and postgraduate students, and a fellow of St Edmund Hall, Oxford. John was a family man, and kept geese and pigs, grew apples and made legendary cider at his old farmhouse home north of Oxford.

Charge-Compensated Derivatives of Nido-Carborane

This review summarizes data on the main types of charge-compensated nido-carborane derivatives. Compared with organic analogs, onium derivatives of nido-carborane have increased stability due to the stabilizing electron-donor action of the boron cage. Charge-compensated derivatives are considered according to the type of heteroatom bonded to a boron atom.

Ferrocene-Based Terpolyamides and Their PDMS-Containing Block Copolymers: Synthesis and Physical Properties

Aromatic polyamides are well-known as high-performance materials due to their outstanding properties making them useful in a wide range of applications. However, their limited solubility in common organic solvents restricts their processability and becomes a hurdle in their applicability. This study is focused on the synthesis of processable ferrocene-based terpolyamides and their polydimethylsiloxane (PDMS)-containing block copolymers, using low-temperature solution polycondensation methodology. All the synthesized materials were structurally characterized using FTIR and 1H NMR spectroscopic techniques. The ferrocene-based terpolymers and block copolymers were soluble in common organic solvents, while the organic analogs were found only soluble in sulfuric acid. WXRD analysis showed the amorphous nature of the materials, while the SEM analysis exposed the modified surface of the ferrocene-based block copolymers. The structure-property relationship of the materials was further elucidated by their water absorption and thermal behavior. These materials showed low to no water absorption along with their high limiting oxygen index (LOI) values depicting their good flame-retardant behavior. DFT studies also supported the role of various monomers in the polycondensation reaction where the electron pair donation from HOMO of diamine monomer to the LUMO of acyl chloride was predicted, along with the calculation of various other parameters of the representative terpolymers and block copolymers.

Differential Metabolomics Reveals Pathogenesis of Pestalotiopsis kenyana Causing Leaf Spot Disease of Zanthoxylum schinifolium.

Pepper leaf spot is a common disease of Zanthoxylum schinifolium. When it is serious, it directly affects the growth of Z. schinifolium, making the plant unable to blossom and bear fruit, which seriously restricts the development of the Z. schinifolium industry. Therefore, the pathogenic mechanism of leaf spots should be explored to provide a basis for a comprehensive understanding of the disease. Using liquid chromatography-mass spectrometry (LC-MS) technology combined with the data-dependent acquisition, the full spectrum analysis of pathogen mycelium samples was carried out. Partial least squares discriminant analysis (PLS-DA) was used to reveal the differences in metabolic patterns among different groups. Hierarchical clustering analysis (HCA) and PLS-DA were used to reveal the relationship between samples and metabolites, which reflected the metabolomics changes of Pestalotiopsis kenyana in the logarithmic growth phase of mycelia, the stable growth phase of mycelia, the massive spore stage, the induction culture conditions of PDA and Z. schinifolium leaves, and the possible pathogenic substances were selected for pathogenicity detection. PLS-DA had a strong predictive ability, indicating a clear analysis trend between different groups. The results of the metabolomics analysis showed that the differential metabolites of pathogenic bacteria were abundant at different stages and under different medium conditions, and the content of metabolites changed significantly. There were 3922 differential metabolites in nine groups under positive and negative ion modes, including lipids and lipid molecules, organic acids and their derivatives, organic heterocyclic compounds, organic oxygen compounds, carbohydrate polyketides, nucleosides, nucleotides, and analogs. The results of the pathogenicity test showed that the leaves treated with 3,5-dimethoxy benzoic acid, S-(5-adenosy)-l-homocysteine, 2-(1H-indol-3-yl) acetic acid, l-glutamic acid, and 2-(2-acetyl-3,5-dihydroxy phenyl) acetic acid showed different degrees of yellowish-brown lesions. This indicated that these substances may be related to the pathogenicity of P. kenyana, and the incidence was more serious when treated with 3,5-dimethoxybenzoic acid and S-(5-adenosy)- l -homocysteine. This study provides a basis for further analysis of differential metabolites and provides a theoretical reference for the prevention and treatment of Z. schinifolium leaf spot.

Effectiveness of Organic Versus Inorganic Analogues for Treating White Spot Lesions: An in Vitro Study

Effectiveness of Organic Versus Inorganic Analogues for Treating White Spot Lesions: An in Vitro Study

Health Equity Is No Spectator Sport: The Radical Rooting of a Post-Pandemic Bioethics.

The relationship between equality and equity has been theorized and described in many ways. Recently, this relationship has been popularly illustrated via a meme depicting three people watching a baseball game while standing on boxes. The meme's analogy, that achieving health equity is the ability to view a spectator sport, is a neoliberal account of health. The analogy defines equality at the expense of equity, characterizes health as individualistic, describes health equity as a static outcome, and implies that the bioethical questions for achieving health equity are about the distribution and redistribution of resources. As the SARS CoV-2 pandemic vividly reminded us, health equity is no spectator sport. Health equity is the intentional removal of obstacles to health and the enabling of human flourishing to assure that everyone has fair and just opportunities for health. That relational and radical account of health equity requires different analogies. This article reimagines and re-illustrates the relationship between equality and equity using an organic analogy of three plants. The analogy calls for bioethics to nurture communal relationships and engage community leaders in pursuit of communal flourishing.

Efficient and selective solid-phase microextraction of polychlorinated biphenyls by using a three-dimensional covalent organic framework as functional coating

Developing functional fiber coating for selective solid phase microextraction (SPME) of trace pollutants is critical in environmental analysis. Herein, the novel covalent organic frameworks (COFs) with three-dimensional (3D) frameworks and multiple interactions were designed and presented for the selective SPME of polychlorinated biphenyls (PCBs). Using tetra (p-aminophenyl) methane (TAM) and 1,3,5-triformylphloroglucinol (Tp) as the monomers, the 3D TpTAM-COF was synthesized and possessed a large specific surface area, high thermal stability, and spatial selectivity toward PCBs. Characterizations such as morphology, XPS, XRD, thermal stability, and enhancement factors (EFs) were studied. Multiple interactions including π-π conjugation, hydrophobic interaction, and selectivity toward non-planar structure were adopted, which resulted in a superior adsorption affinity toward PCBs on TpTAM-COF. Under the optimal conditions, the spatial selectivity toward PCBs, organic analogs (o-dichlorobenzene, biphenyl) and polycyclic aromatic hydrocarbons (naphthalene, pyrene, and anthracene)) was achieved. Efficient and selective adsorption of fifteen PCBs was fulfilled with the highest EF up to 10305. Using the HS-SPME-GC-MS method, the recoveries of PCBs in the river water and soil samples were determined to be 84.8 ± 7.8% ∼ 117.2 ± 8.5% (n = 3) and 84.4 ± 8.6% ∼ 114.7 ± 7.6% (n = 3), respectively. Compared with most commercial SPME fibers and other COFs-based fibers, the resultant TpTAM-COF-coated fibers possessed higher selectivity and EFs of PCBs. It proposed a promising approach for selective SPME of trace PCBs by multiple interactions in the steric structure of 3D COFs.

Giant Multi-Photon Absorption by Heptazine Organometalation.

Multi‐photon absorption (MPA) is of increasing interest for applications in technologically important “windows” of the electromagnetic spectrum (near‐infrared III, NIR‐III, 1550–1870 nm; and the new 2080–2340 nm region); however, few molecules exist that display strong MPA at these long wavelengths. We herein report the syntheses of the first 2,5,8‐s‐heptazine‐cored organometallic complexes, together with organic analogues. The complexes exhibit outstanding 3PA cross‐sections in the NIR‐III and exceptional 4PA cross‐sections in the new 2080–2340 nm window. We demonstrate that replacing organic donor groups by organometallic units results in an order of magnitude increase in 3PA, the “switching on” of 4PA, and a dramatic improvement in photo‐stability. Our results highlight the impressive outcomes possible with an “organometalation” approach to NLO materials design.

Giant Multi‐Photon Absorption by Heptazine Organometalation

AbstractMulti‐photon absorption (MPA) is of increasing interest for applications in technologically important “windows” of the electromagnetic spectrum (near‐infrared III, NIR‐III, 1550–1870 nm; and the new 2080–2340 nm region); however, few molecules exist that display strong MPA at these long wavelengths. We herein report the syntheses of the first 2,5,8‐s‐heptazine‐cored organometallic complexes, together with organic analogues. The complexes exhibit outstanding 3PA cross‐sections in the NIR‐III and exceptional 4PA cross‐sections in the new 2080–2340 nm window. We demonstrate that replacing organic donor groups by organometallic units results in an order of magnitude increase in 3PA, the “switching on” of 4PA, and a dramatic improvement in photo‐stability. Our results highlight the impressive outcomes possible with an “organometalation” approach to NLO materials design.

Pinecone Analogy Approach in Designing Low Energy Apartment

Limited land available in big capital cities makes building development change from horizontal into vertical one. High demand for living space along with high-density population causes carbon emissions from electricity used for lighting and cooling increasing as well. This research is trying to invent vertical housing design concept that responsive into environment, especially Bengkulu City, as the solution and alternative for living space that low in energy used. Organic analogy was used as a method to conduct natural principles of Australian Pinecone into apartment design. Pinecone physical appearance and the structure of Pinecone transversal section were interpreted as an apartment plan configuration and exterior design of the building. First, the transversal section of Pinecone structure that consists of seed, wing, and axis, were interpret as an apartment plan configuration, which is the balcony area, apartment unit, and corridor. Next, the spike shape of Pinecone scale inspires angular shape on the outer side area of apartment floor plan and the façade as well. There are three alternatives from design process iteration that later being analyzed using Sefaira simulation to find energy use in the building. Result showed that apartment building design that use a lot of Pinecones principle analogy has lower energy consumption, which is 63 KWh/year/m2. This number is still under the average energy use intensity for apartment building in Indonesia. Nevertheless, there are still some limitations and minus point on the final design that can be further research in the future.

Recent Advances in Light‐Induced Carboxylation of Organic (Pseudo)Halides with CO2

AbstractCarbon dioxide is an ideal C1 source in organic synthesis as a precursor for the carboxyl group. With the development of photocatalysis, the carboxylation reactions with CO2 incorporation could be carried out in a more environmental and sustainable manner without the addition of stoichiometric metallic reductants. This minireview summarizes the recent development in light‐induced carboxylation of organic (pseudo)halides and analogues with CO2 via C−X (X=Br, Cl, O, N, etc.) bond cleavage.

A printed proximity-sensing surface based on organic pyroelectric sensors and organic thin-film transistor electronics

Large-area, flexible proximity-sensing surfaces are useful in a range of applications including process control, work security and robotics. However, current systems typically require rigid and thick electronics, which limit how they can be used. Here we report a flexible large-area proximity-sensing surface fabricated using printed organic materials and incorporating analogue front-end electronics in each pixel. The sensing surface is built with printed thin-film pyroelectric sensors based on poly(vinylidene fluoride-co-trifluoroethylene) co-polymers and printed organic thin-film transistors. A 5 × 10 matrix frontplane, consisting of long-wavelength infrared organic pyroelectric sensors, is laminated with an organic transistor analogue front-end backplane. The electronic front end provides sensor-signal amplification and pixel addressing to maximize the detection distance and reduce pixel crosstalk. An average yield of 82% fully working pixels for the backplane and a maximum system yield of 96%, which corresponds to 768 defect-free devices, are achieved. The system can detect a human hand approaching from different directions and track the position of a movable heat source up to a distance of around 0.4 m at a readout speed of 100 frames per second.

Facile Synthesis of Ferrocene-Based Polyamides and Their Organic Analogues Terpolyamides: Influence of Aliphatic and Aromatic Sequences on Physico-Chemical Characteristics

Efforts have been devoted to synthesize and characterize processable polymers with desired properties. Herein, four different series of aromatic and aliphatic terpolyamides were prepared via solution phase polycondensation of 4,4′-oxydianiline and hexamethylenediamine (HMDA) with various diacids chlorides (isophthalyol dichloride, terepthalyol dichloride, 1, 1′-ferrocene dicarboxylic acid chloride and trans-azobenzene-4, 4′-dicarbonyl chloride). The structural, morphological and physico-chemical nature of as prepared polymers was explored by Fourier-transform infrared spectroscopy, scanning electron microscopy, thermal analysis (TGA and DSC), and wide-angle x-ray diffraction. Moreover, an aliphatic diamine was incorporated in varying concentration as a flexible methylene spacer and the effect of its concentration on the properties of polyamides was also studied. Changes in various physico-chemical properties such as solubility, inherent viscosity, surface morphology and flame retarding behaviour were investigated. Marked difference in morphology and solubility was observed with the change in the ratio of segments in the chain. Inherent viscosities of polymers ranged from 1.8052–1.6274 dl/g indicating reasonably moderate molecular weights. Interestingly, ferrocene based aromatic polymers were more thermally stable (Tg 260 °C, Ti 310 °C, Th 525 °C, Tf 720 °C, for PF0), and also found to exhibit best flame retarding behavior (limiting oxygen index value for PF0is LOI 33.15%).

Cyrhetrenyl and cymantrenyl N-acylhydrazone complexes based on isoniazid: Synthesis, characterization, X-ray crystal structures and antitubercular activity evaluation

Four organometallic N-acylhydrazones of the general formulae [M{(η5-C5H4)-CHNNHC(O)-(C5H4N)}(CO)3] [(with M = Re (5a) or Mn (6a)] and [M{(η5-C5H4)-C(Me)=NNHC(O)-(C5H4N)}(CO)3] [(with M = Re (5b) or Mn (6b)] were prepared by reaction of aldehyde/methyl ketone organometallic precursors with isoniazid (INH). All compounds were fully characterized using conventional spectroscopic techniques (FT-IR, 1H and 13C{1H} NMR, mass spectrometry, and high-resolution mass spectrometry). The X-ray crystal structures of cyrhetrenyl compounds (5a and 5b) are also reported. This structural analysis indicated that both compounds exhibited an E-configuration of the substituents on the -C(R1)=N- (R1 = H or Me). The biological activity of the four analogous organometallic compounds (5 and 6) to INH and their organics counterpart {[(C6H5)-C(R)=NNHC(O)-(C5H4N)] where R = H (NAHH) or R = Me (NAH-Me)} were evaluated on Mycobacterium tuberculosis (M. tuberculosis) in the standard strain H37Rv ATCC 27,294. The replacement of a hydrogen atom by a methyl group on the acylhydrazone moiety led to a significant increase in antitubercular properties. The compounds 5b and 6b (R1 = Me) were at least 36- and 18-fold more effective than 5a and 6a (R1 = H), respectively. The cyrhetrenyl derivative (5b) was the most active complex against M. tuberculosis. This compound was shown to be about 2-times more effective than its organic analog (NAH-Me) and showed activity comparable to antitubercular drug INH. In vitro toxicity assays against murine macrophage cells J774A.1 (ATCC TIB-67) were also conducted, and selectivity indexes were determined for the most promising compounds. All N-acylhydrazones showed a moderated cytotoxic profile, similar to the isoniazid and rifampicin (RIF) control drugs, while 5b exhibited better selectivity index (SI) concerning the organic counterpart NAH-Me. Based on the anti-TB activity, cytotoxicity, and selectivity index, compound 5b has more potential for evolution as a new antitubercular agent.

Advanced Strategies for 3D Bioprinting of Tissue and Organ Analogs Using Alginate Hydrogel Bioinks.

Alginate is a natural polysaccharide that typically originates from various species of algae. Due to its low cost, good biocompatibility, and rapid ionic gelation, the alginate hydrogel has become a good option of bioink source for 3D bioprinting. However, the lack of cell adhesive moieties, erratic biodegradability, and poor printability are the critical limitations of alginate hydrogel bioink. This review discusses the pivotal properties of alginate hydrogel as a bioink for 3D bioprinting technologies. Afterward, a variety of advanced material formulations and biofabrication strategies that have recently been developed to overcome the drawbacks of alginate hydrogel bioink will be focused on. In addition, the applications of these advanced solutions for 3D bioprinting of tissue/organ mimicries such as regenerative implants and in vitro tissue models using alginate-based bioink will be systematically summarized.

Exogenous sulphide donors modify the gene expression patterns of Atlantic salmon nasal leukocytes

Hydrogen sulphide (H2S) is a known mediator of immunity, but the regulatory function of its exogenous form is not well understood in fish particularly in the mucosa. Here we report transcriptomic changes in the nasal leukocytes of Atlantic salmon (Salmo salar) following exposure to two forms of H2S donors – the salt sodium hydrosulfide (NaHS) and the organic analogue morpholin-4-ium 4-methoxyphenyl (morpholino) phosphinodithioate (GYY4137). Nasal leukocytes were exposed to three concentrations (1, 10 and 100 μM) of either of the two H2S forms for 24 h before the cells were checked for viability and collected for microarray analysis. Though cellular viability was minimally affected by the exposure to two H2S donors, GYY4137-exposed cells exhibited reduced viability compared with the NaHS group at the highest dose. The H2S-induced transcriptomic changes in the nasal leukocytes were concentration-dependent regardless of the sulphide forms. However, a larger number of differentially expressed genes (DEGs) were identified in the NaHS-exposed versus GYY4137-exposed groups across concentrations. In all comparisons, at least 53% of the DEGs identified were significantly upregulated. Gene ontology (GO) terms enriched in the lists of upregulated DEGs at higher concentrations included ferric iron binding. A comparison of the two H2S forms showed a clear grouping of different GO terms relative to concentrations. Pathway enrichment analysis revealed a significant influence in VEGF ligand-receptor interactions, oxidative stress, innate and adaptive immunity, and interleukin signalling especially at higher concentrations. Congruence analysis demonstrated that there were 16 GO terms overlapping; of these, 12 were upregulated by both sulphide donors including several involving iron binding and transport. The study offers the first molecular insights into how fish nasal leukocytes respond to exogenous H2S, and the results will be vital in resolving the regulatory function of H2S on mucosal immunity in fish.

Selective removal of organic phosphonates via coupling hyper-cross-linked resin with nanoconfined hydrated oxides

Phosphonates, featuring organic skeletons binding phosphonic acid group, are ubiquitous in wastewaters and natural waters. Highly efficient removal of trace phosphonates is desirable to ensure the water quality and to prevent eutrophication. Commercially available hyper-cross-linked resins modified by amino groups have been proved to exhibit preferable adsorption of various organic acids from aqueous systems via synergetic effect of various interactions (electrostatic interaction, van der Waals interaction, π-π interaction, etc.) but seem relatively ineffective for phosphonates. In this study, we proposed a new strategy via coupling a commercial resin NDA88 with nanoconfinement of Hydrated ferric oxide (HFO) for selective removal of phosphonates. The resultant HFO@NDA88 shows an adsorption capacity of 15.0 mg P/g towards a model phosphonate (nitrilotris(methylenephosphonic acid)), higher than those of the NDA88 host (7.9 mg P/g) and the bare HFO (7.4 mg P/g). Remarkably, compared to NDA88 and HFO, HFO@NDA88 exhibits much higher resistance to the interference of various anions and other substances at much greater levels, particularly the organic analogue nitrilotriacetic acid and phosphate. Such superior selectivity is believed to result from the cooperative contributions of the host NDA88 as well as the embedded nano-HFO. Moreover, HFO@NDA88 shows excellent reusability and satisfactory performance in fixed-bed water treatment. This work provides a rational design of nanocomposite adsorbents for highly selective removal of phosphonates from complicated water matrix.

Cover Feature: Group 14 Central Atoms and Halogen Bonding in Different Dielectric Environments: How Germanium Outperforms Silicon (ChemPlusChem 10/2021)

The Cover Feature shows the Group 14 elements M=C, Si, and Ge in order of the effective electron-withdrawing power of the −MF3 fragment. C and Ge far outperform Si in mediating polarization of a fourth substituent such as I in F3M−I in the gas and solution phases. Thus, polarized germanium halide sites in molecules and solids (but not Si alternatives) may form strong halogen bonds that are comparable to those formed by their organic analogues. More information can be found in the Full Paper by K. J. Donald and co-workers.

Exploring the link between molecular cloud ices and chondritic organic matter in laboratory

Carbonaceous meteorites are fragments of asteroids rich in organic material. In the forming solar nebula, parent bodies may have accreted organic materials resulting from the evolution of icy grains observed in dense molecular clouds. The major issues of this scenario are the secondary processes having occurred on asteroids, which may have modified the accreted matter. Here, we explore the evolution of organic analogs of protostellar/protoplanetary disk material once accreted and submitted to aqueous alteration at 150 °C. The evolution of molecular compounds during up to 100 days is monitored by high resolution mass spectrometry. We report significant evolution of the molecular families, with the decreases of H/C and N/C ratios. We find that the post-aqueous products share compositional similarities with the soluble organic matter of the Murchison meteorite. These results give a comprehensive scenario of the possible link between carbonaceous meteorites and ices of dense molecular clouds.