Propyl Chain Research Articles

Investigating the Effect of Incorporating Dimethylaminopropyl Side Chains into a Naphthalenediimide‐Based Conjugated Polymer

AbstractTwo approaches—fractional side‐chain truncation and complementary interactions—are employed in this study. In fractional side‐chain truncation, NDIDmap with the naphthalene diimide (NDI) group and the 3‐(dimethylamino)propyl (Dmap) chain is incorporated into P(NDI2OD‐T2), yielding various copolymers. Increasing the amount of NDIDmap in the polymer enhances π‐isotropy, which can improve charge transport. In complementary interactions, the NDIDmap group complexes with tris(pentafluorophenyl)borane (BCF) via complementary N–B interactions. Adding BCF to a naphthalenediimide‐based conjugated polymer with NDIDmap enhances the coherence length (Lc) of π‐stacking. However, the elongated Lc does not result in superior electron mobility, challenging the conventional perspective that long‐range π‐order is crucial for charge transport. For comparison, triphenylamine (TPA), which is electronically distinct from BCF, is used. TPA affects the thin‐film microstructure and charge‐transport parameters differently from BCF. Although the improvement in electron mobility is not very significant, this study demonstrates the effects of fractional side‐chain truncation and complementary interactions on the thin‐film microstructure and charge transport of naphthalenediimide‐based conjugated polymers, paving the way for further side‐chain engineering.

Unique Crystal Structure of a Self-Assembled Dinuclear Cu Peptoid Reveals an Unusually Long Cu···Cu Distance.

Studies on a series of molecular dicopper peptoid complexes showed that the Cu···Cu distances measured in X-ray single-crystal diffraction are typically in the range of 4.2-6.9 Å. Herein, we designed a new peptoid, L1, having 2,2'-bipyridine, propyl, and pyridyl side chains and discovered that although it forms a typical dicopper self-assembled structure (complex 1), the Cu···Cu distance is exceedingly long -8.043 Å. By analyzing its structure and surface properties in comparison to a control Cu-peptoid complex (2), in which the pyridyl side chain is modified by an ethanolic side chain, we suggest that the long Cu···Cu distance is contributed by the hydrophilic-hydrophobic interaction influenced by the pyridyl side chain and the steric hindrance of the propyl side chain. This result may motivate the use of dinuclear Cu peptoid complexes for wider applications, such as cooperative catalysis and luminescence.

Catalytic depolymerization of Camellia oleifera shell lignin to phenolic monomers: Insights into the effects of solvent, catalyst and atmosphere

Camellia oleifera shell (COS) is a renewable biomass resource abundant in lignin with significant potential for producing phenolic monomers. However, the dearth of research has led to considerable resource wastage and environmental pollution. Herein, reductive catalytic fractionation (RCF) of COS was performed using noble metal catalysts in different solvents. An 11.1 wt% yield of phenolic monomers was achieved with 91% selectivity toward propylene-substituted monomers in H2O/EtOH (3:7, v/v) cosolvent under N2 atmosphere. Notably, the highest phenolic monomer yield of 17.0 wt% was obtained with impressive selectivity (86.9%) toward propanol-substituted monomers in the presence of H2. The GPC analysis and 2D HSQC NMR spectra indicated the effective depolymerization of lignin oligomers with catalysts. Phenolic monomers with ethyl, propyl, or propanol side chain could be produced from lignin-derived oligomers through hydrogenolysis, hydrogenation, and decarboxylation reactions. Overall, this study has paved the way for the valorization of COS lignin through the RCF strategy.

Tetrapodal Hole-Collecting Monolayer Materials Based on Saddle-Like Cyclooctatetraene Core for Inverted Perovskite Solar Cells.

Hole-collecting monolayers have greatly advanced the development of positive-intrinsic-negative perovskite solar cells (p-i-n PSCs). To date, however, most of the anchoring groups in the reported monolayer materials are designed to bind to the transparent conductive oxide (TCO) surface, resulting in less availability for other functions such as tuning the wettability of the monolayer surface. In this work, we developed two anchorable molecules, 4PATTI-C3 and 4PATTI-C4, by employing a saddle-like indole-fused cyclooctatetraene as a π-core with four phosphonic acid anchoring groups linked through propyl or butyl chains. Both molecules form monolayers on TCO substrates. Thanks to the saddle shape of a cyclooctatetraene skeleton, two of the four phosphonic acid anchoring groups were found to point upward, resulting in hydrophilic surfaces. Compared to the devices using 4PATTI-C4 as the hole-collecting monolayer, 4PATTI-C3-based devices exhibit a faster hole-collection process, leading to higher power conversion efficiencies of up to 21.7 % and 21.4 % for a mini-cell (0.1 cm2) and a mini-module (1.62 cm2), respectively, together with good operational stability. This work represents how structural modification of multipodal molecules could substantially modulate the functions of the hole-collecting monolayers after being adsorbed onto TCO substrates.

A 3-D nanostructure polyhedral oligomeric silsesquioxane as a (co)-crosslinker of an epoxy resin

Epoxy resins have outstanding properties with variety uses especially in high performance engineering applications. However, high degree of crosslinking density makes them rigid and brittle. Many attempts have been used to improve mechanical properties, especially toughness. In the current work, synergistic properties of using the polyhedral oligomeric silsesquioxane nanostructure (POSS) and polyether amine chains has been used to improve toughness and mechanical properties especially modulus by using the synthesized structure as co-curing agent in epoxy resin. The characteristic analysis showed that the structure of the synthesized molecule is a POSS core with four polyether amine chains and four glycidyloxy propyl chains attached to the siloxane cage. The results indicated that using the synthesized structure (GA-POSS) as co-curing agent has two effects: it acted like a reinforcing agent and improve glass transition temperature, toughness and Young’s modulus. Also, it increased distance between crosslinks which led to increase of tan δ and elongation at break. However, these effects did not observed when this nano-molecule worked as cross linker or when the POSS structure doesn’t have soft long chains because just in the case of using GA-POSS as co-curing agent hard-soft-hard state is formed which leads to high mechanical and toughness properties, simultaneously.

Synthesis and characterization of SBA-15 silica containing cyclam inside pores for capturing iron chloride: Analysis of interactions between ferrous chloride and cyclam in a system with strongly dispersed functional groups on the SiO2 surface

The use of the spatial structure of mesoporous silica combined with organic molecules opens up a wide range of possibilities in the field of separation of single atoms and the precise creation of their environment. Materials obtained in this way can find applications as single-atom catalysts (SAC) and in environmental applications in ion and molecule trapping processes. An example of such a material is silica of the SBA-15 type functionalized with cyclam (1,4,8,11-tetraazacyclotetradecane) anchored inside the pores with propyl chains. In this work, we present such a material containing 5% functional groups, additionally activated with iron(II) chloride, which was chelated by cyclam anchored inside the pores of silica. The presented nanocomposite has been thoroughly tested for its assumed molecular structure and stability. We compared it to a material containing only cyclam. The obtained results showed the high efficiency of the silica matrix with cyclam in the separation of single FeCl2 molecules and the correct molecular structure of the obtained material. The nanocomposite containing chelated molecules with iron showed good stability, while the structure of the material with cyclam alone collapsed with time.

Influence mechanisms of torrefaction on syngas production from bio-waste molten salt thermal treatment

The production of high-value syngas from bio-wastes through thermal conversion is a promising way to achieve carbon neutrality. In order to reduce the cost of the process, molten salt thermal treatment has been used for bio-wastes syngas production. Moreover, the removal of oxygen and water induced by torrefaction can effectively enhance the energy density of biomass, and the effect of these changes on the quality of syngas was widely investigated. This study proposed to torrefy bio-wastes and then produce syngas in molten NaNO3-NaNO2-KNO3 at 300 ℃. Results showed that the evaluation indices of syngas were improved, while the cold gas efficiency reached 44.02 % for beech wood torrefied at 280 ℃, and the syngas quality is equivalent to the products obtained by gasification of bio-wastes. The gas yield of the torrefied bio-wastes was increased by 8.08–45.23 % compared to the raw bio-wastes. Na+ and K+ in the molten salt catalyzed the cracking of propyl chains and ring opening of aromatic rings in lignin, resulting in a prominent enhancement in CO yield. Meanwhile, torrefaction could change the solid structure, leading to a delay in gas production, and torrefaction could also increase graphitization degree of char (C–C/C = C up to 50.72 % for SB-280), thus preventing the reaction proceeding. This study provided a new approach to enhance the content and quality of syngas from bio-wastes at low temperatures.

Chiral separation and bioactivities of six pairs of enantiomeric dilignans from Magnolia officinalis var. biloba

Six pairs of enantiomeric dilignans, (+)/(−)-magdiligols A–F, have been isolated from an ethanolic extract of the barks of Magnolia officinalis var. biloba. Their chemical structures were elucidated by extensive spectroscopic analyses, NMR calculation with DP4+ analysis, and the electronic circular dichroism spectra calculation. (+)/(−)-1–3 possessed a dihydrobenzopyran ring, while a propyl chain of 1 was linked via ether bond. (+)/(−)-Magdiligols D and E ((+)/(−)-4 and 5) were dilignans possessing a furan ring. (+)-Magdiligol B ((+)/(−)-2), (+)/(−)-magdiligol C ((+)/(−)-3), and racemes 2, 3, and 5 showed potential hepatoprotective effects against APAP-induced HepG2 cell damage, increased the cell viability from 65.4% to 72.7, 78.7.76.6, 73.9, 77.9 and 73.2%, via decreasing the level of the live enzymes ALH and LDH consistently. (+)/(−)-Magdiligols B–D ((+)/(−)-2–4) and (+)/(−)-magdiligol F ((+)/(−)-6) exhibited significant antioxidative activity. (+)/(−)-Magdiligols B–C ((+)/(−)-2 and 3), (−)-magdiligol D ((−)-4), and (+)-magdiligol E ((+)-5) displayed significant PTP1B inhibitory activity with IC50 values 1.41–3.42 μM. (+)/(−)-Magdiligol B ((+)/(−)-2), and its raceme (2) demonstrated α-glucosidase inhibitory activity with the IC50 values 1.47, 2.88 and 1.85 μM, respectively.

A stable hybrid catalyst (POM-PPPh3/L/Ni) for the reduction of toxic nitroarene compounds in water.

Reduction of nitroarenes to aminoarenes using novel and selective catalysts is an important and desirable approach in green chemistry. In this work, a new heterogeneous nanocatalyst, POM-PPPh3/L/Ni, was designed and prepared via functionalizing a Keggin-type polyoxometalate (H3PMo12O40) with (3-bromopropyl)triphenylphosphonium bromide (BPPPh3Br) through strong electrostatic interactions to prepare [PMo12O40][PPPh3]3 (denoted as POM-PPPh3). The obtained compound was modified via nucleophilic attack of the nitrogen donor of a multidentate Schiff base ligand (L) on its propyl chain to produce [PMo12O40][PPPh3/L]2 (denoted as POM-PPPh3/L), which was finally metallated with nickel cations to achieve [PMo12O40][PPPh3/L/Ni]2 (denoted as POM-PPPh3/L/Ni). After full characterization of the prepared material with various physicochemical methods, its catalytic behavior was investigated in the catalytic nitroarene reduction. The influence of various factors on catalytic conversion and selectivity was considered. The synthesized nanocatalyst showed excellent performance in the reduction of nitroarenes in aqueous media in the presence of NaBH4 as a reducing agent. Mild reaction conditions and a short reaction time (10 min) are the prominent features of this new nanocatalyst. In addition, the catalyst was recovered and reused for up to four cycles of catalytic reduction without any significant loss of conversion.

3-Glycidoxypropyltrimethoxysilan: Description, and Analysis of Works Approaches and Applications

3-Glycidoxypropyltrimethoxysilan, also known as GPTMS, is a versatile organosilane compound that has gained significant attention in various fields. Its unique chemical structure, consisting of a glycidoxy group and three methoxy groups attached to a propyl chain, enables it to exhibit exceptional reactivity and compatibility with different materials. In the literature, extensive research has been conducted to understand the properties and behavior of GPTMS. Studies have focused on its synthesis methods, All of the GPTMS work is discussed and evaluated in this article. The work done in various areas of GPTMS has also been assessed. We have discovered and discussed all of the applications of GPTMS as well as its physical and chemical properties. In conclusion, here is the complete GPTMS description. We have covered all of the GPTMS applications as well as all of the experimental work done on them, including sol-gel pressure synthesis, hybrid coating sol-gel processes, cellulose-based sensors, etc.

Synthesis and anti-cancer potential of potent peripheral MAOA inhibitors designed to limit blood:brain penetration

Monoamine oxidases (MAOA/MAOB) are enzymes known for their role in neurotransmitter regulation in the central nervous system (CNS). Irreversible and non-selective MAO inhibitors (MAOi’s) were the first class of antidepressants, thus subsequent work on drugs such as the selective MAOA inhibitor clorgyline has focussed on selectivity and increased CNS penetration. MAOA is highly expressed in high grade and metastatic prostate cancer with a proposed effect on prostate cancer growth, recurrence, and drug resistance. A Phase II Clinical Trial has demonstrated the therapeutic effects of the irreversible nonselective MAOi phenelzine for prostate cancer. However, neurologic adverse effects led to early withdrawal in 25% of the enrolled patient-population. In this work, we revised the clorgyline scaffold with the goal of decreasing CNS penetration to minimize CNS-related side effects while retaining or enhancing MAOA inhibition potency and selectivity. Using the known co-crystal structure of clorgyline bound with FAD co-factor in the hMAOA active site as a reference, we designed and synthesized a series of compounds predicted to have lower CNS penetration (logBB). All synthesized derivatives displayed favorable drug-like characteristics such as predicted Caco-2 permeability and human oral absorption, and exhibited highly selective hMAOA binding interactions. Introduction of an HBD group (NH2 or OH) at position 5 of the phenyl ring clorgyline resulted in 3x more potent hMAOA inhibition with equivalent or better hMAOB selectivity, and similar prostate cancer cell cytotoxicity. In contrast, introduction of larger substituents at this position or at the terminal amine significantly reduced the hMAOA inhibition potency, attributed in part to a steric clash within the binding pocket of the MAOA active site. Replacement of the N-methyl group by a more polar, but larger 2-hydroxyethyl group did not enhance potency. However, introduction of a polar 2-hydroxy in the propyl chain retained the highly selective MAOA inhibition and cancer cell cytotoxicity of clorgyline while reducing its CNS score from 2 to 0. We believe that these results identify a new class of peripherally directed MAOIs that may allow safer therapeutic targeting of MAOA for a variety of anti-cancer and anti-inflammatory indications.

Expanding the Chemical Space of Arsenicin A-C Related Polyarsenicals and Evaluation of Some Analogs as Inhibitors of Glioblastoma Stem Cell Growth

The marine polyarsenical metabolite arsenicin A is the landmark of a series of natural and synthetic molecules characterized by an adamantane-like tetraarsenic cage. Arsenicin A and related polyarsenicals have been evaluated for their antitumor effects in vitro and have been proven more potent than the FDA-approved arsenic trioxide. In this context, we have expanded the chemical space of polyarsenicals related to arsenicin A by synthesizing dialkyl and dimethyl thio-analogs, the latter characterized with the support of simulated NMR spectra. In addition, the new natural arsenicin D, the scarcity of which in the Echinochalina bargibanti extract had previously limited its full structural characterization, has been identified by synthesis. The dialkyl analogs, which present the adamantane-like arsenicin A cage substituted with either two methyl, ethyl, or propyl chains, were efficiently and selectively produced and evaluated for their activity on glioblastoma stem cells (GSCs), a promising therapeutic target in glioblastoma treatment. These compounds inhibited the growth of nine GSC lines more potently than arsenic trioxide, with GI50 values in the submicromolar range, both under normoxic and hypoxic conditions, and presented high selectivity toward non-tumor cell lines. The diethyl and dipropyl analogs, which present favorable physical-chemical and ADME parameters, had the most promising results.

Light and thermally activated spin crossover coupled to an order–disorder transition of a propyl chain in an iron(iii) complex

A series of three solvates [Fe(naphPren)2]I·CH2Cl21, [Fe(naphPren)2]I·CHCl32 and [Fe(naphPren)2]I·acetone 3 showing thermal and light-induced spin crossover is reported.

Synthesis and characterization of thermoplastic poly(piperazine succinate) metallopolymers coordinated to ruthenium(III) or iron(III)

AbstractMetal‐containing polymers represent an ever‐expanding frontier of material science. Of the numerous biocompatible ligands used to create a metallopolymer, piperazine‐containing polymers are still in their early development, even though piperazine is a common functional group in drug design and bioengineering scaffolding elements. We report the first synthesis and characterization (with NMR, IR, GPC, UV–vis spectroscopy, and thermal analysis) of two thermoplastic poly(alkyl piperazine succinate) diols with either propyl or hexyl alkane chains bridging the piperazines. These polyester diols were then chain extended with hexamethylene diisocyanate to create highly amorphous polyester urethane thermoplastic polymers. Ru(III) or Fe(III) was then successfully coordinated with these polymers, with approximately 30% of the bulk metallopolymer product becoming 250x the molecular weight of the non‐metal containing polymers. However, coordination of Fe(III), and to a lesser extent Ru(III), to these polypiperazines accelerated the hydrolysis of the polyester linkage in water over 15 days. Thus, these novel polymers are highly biodegradable with Fe(III) metallopolymers hydrolyzing faster than Ru(III) metallopolymers and poly(propyl piperazine succinate) polymers hydrolyzing faster than poly(hexyl piperazine succinate) polymers.

Molecular design of efficient SO3H-functionalized ionic liquid to catalyse chitin into levulinic acid: NMR and DFT study

Although chitin is the second abundant natural biomass after cellulose, investigations on chitin conversion are still limited. Levulinic acid (LA) is versatile biorefinery platform chemical. The SO3H-functionalized ILs present excellent catalytic activity to transfer biomass into LA. To improve the yield of LA and select the IL with higher catalytic activity, the relationship between the structure of SO3H-functionalized ILs and their catalytic capacities for LA production from chitin are explored with the 1H NMR and density functional theory (DFT) methods in this work. First, the catalytic activities of the selected ILs were predicted by the DFT methods. Then, they were confirmed by the 1H NMR experiments. The order of the catalytic activity of the ILs for chitin conversion into LA is consistent with the sequence of the gap of the LUMO-HOMO of the most stable IL- N-acetylglucosamine (NAG) complexes. The imidazolium-based ILs show the best catalytic activity, followed by the pyridinium-based and ammonium-based ILs. The ILs with butyl chain have stronger catalytic activity than those with propyl chain. Based on the 1H NMR and DFT results, the [C4SO3Hmim]HSO4 was selected to catalyse chitin conversion into LA. The maximum yield of LA is 74.7 % achieved at 5 h reaction time, 190 ℃, 6.0 g water, 1.5 g [C4SO3Hmim]HSO4 catalyst and 0.1 g chitin.

Synthesis, Docking Studies and Pharmacological Evaluation of Serotoninergic Ligands Containing a 5-Norbornene-2-Carboxamide Nucleus.

A new series of 5-norbornene-2-carboxamide derivatives was prepared and their affinities to the 5-HT1A, 5-HT2A, and 5-HT2C receptors were evaluated and compared to a previously synthesized series of derivatives characterized by exo-N-hydroxy-5-norbornene-2,3-dicarboximidenucleus, in order to identify selective ligands for the above-mentioned subtype receptors. Arylpiperazines represents one of the most important classes of 5-HT1AR ligands, and recent research concerning new derivatives has been focused on the modification of one or more portions of such pharmacophore. The combination of structural elements (heterocyclic nucleus, propyl chain and 4-substituted piperazine), known to be critical to the affinity to 5-HT1A receptors, and the proper selection of substituents led to compounds with high specificity and affinity towards serotoninergic receptors. The most active compounds were selected for further in vivo assays to determine their functional activity. Finally, to rationalize the obtained results, molecular docking studies were performed. The results of the pharmacological studies showed that Norbo-4 and Norbo-18 were the most active and promising derivatives for the serotonin receptor considered in this study.

Adsorption Dynamics of Surface-Modified Silica Nanoparticles at Solid-Liquid Interfaces.

Understanding the adsorption dynamics of nanoparticles at solid-liquid interfaces is of paramount importance to engineer nanoparticles for a variety of applications. The nanoparticle surface chemistry is significant for controlling the adsorption dynamics. This study aimed to experimentally examine the adsorption of surface-modified round-shaped silica nanoparticles (with an average diameter of 12 nm), grafted with hydrophobic (propyl chains) and/or hydrophilic (polyethylene glycol chains) agents, at an aqueous solution-silica interface with spherical soda-lime glass beads (diameter of 3 mm) being used as adsorbents. While no measurable adsorption was observed for solely hydrophobic or hydrophilic nanoparticles, a considerable level of adsorption was detected for nanoparticles comprising both hydrophobic and hydrophilic agents. Various kinetic models were employed to model the adsorption dynamics of the responsive nanoparticles. The results demonstrated that the mixed diffusion-kinetics models could predict the dynamics better than the adsorption diffusion models, indicating that the dynamics is controlled by a combination of liquid film diffusion, intra-particle diffusion, and mass action. Additionally, the adsorption of the surface-modified silica nanoparticles onto a mineral silica surface was examined using molecular dynamics simulations. The interaction energy for nanoparticles comprising both hydrophobic and hydrophilic agents was evaluated to be more favorable than that of solely hydrophobic or hydrophilic nanoparticles.

Unbalanced racemates: solid state solutions containing enantiomeric pairs crystallizing in Sohncke space groups with (L:D) ratios other than (1:1) – illustrated with crystals of a Co(III) coordination compound

Abstract Herein we describe materials of composition [Co(NH3)4(X-leucinato)]I2·H2O in which the amino acid ligand is either L or D, and in which (a) while in pure enantiomorphic form (L), crystallizes in a Sohncke space group with Z′ = 2.0; but, whose packing closely resembles that of its racemate. Such substances are labeled a Racemic Mimic; and (b) crystals in which the L:D ratio of the amino acid ligand in the asymmetric unit is (71:29), which interestingly crystallize in the same space group and cell constants as those of the former. Moreover, the packing behavior is essentially the same in both—the difference being that the (1:1) species is fully ordered, while that with L:D (71:29) ratio has a partially disordered propyl chain. The (71:29) species we describe herein as an Unbalanced Racemate.

π-Pimer, π-Dimer, π-Trimer, and 1D π-Stacks in a Series of Benzene Triimide Radical Anions: Substituent-Modulated π Interactions and Physical Properties in Crystalline State

π-Pimer, π-Dimer, π-Trimer, and 1D π-Stacks in a Series of Benzene Triimide Radical Anions: Substituent-Modulated π Interactions and Physical Properties in Crystalline State

Design and synthesis of ibuprofen-quinoline conjugates as potential anti-inflammatory and analgesic drug candidates

A new set of ibuprofen-quinoline conjugates comprising quinolinyl heterocycle and ibuprofen moieties linked by an alkyl chain were synthesized in good yields utilizing an optimized reaction procedure in a molecular hybridization approach to overcome the drawbacks of the current non-steroidal anti-inflammatory drugs. The synthesized conjugates were screened for their anti-inflammatory, and ulcerogenic properties. Several conjugates were found to have significant anti-inflammatory properties in the carrageenan-induced rat paw edema test without showing any ulcerogenic liability. In addition, most conjugates showed promising peripheral analgesic activity in the acetic acid-induced writhing test as well as central analgesic properties in the in vivo hot plate test. The most promising conjugates were the unsubstituted and 6-substituted fluoro- and chloro-derivatives of 2-(trifluoromethyl)quinoline linked to ibuprofen by a propyl chain. Their anti-inflammatory activity was evaluated against LPS-stimulated inflammatory reactions in RAW264.7 mouse macrophages. In this regard, it was found that most of the conjugates were able to significantly reduce the release and production of nitric oxide in the LPS-stimulated macrophages. The secretion and expression of the pro-inflammatory cytokines IL-6, TNF-α, and inducible nitric oxide synthase (iNOS) were also significantly suppressed.