Butyl Chain Research Articles

Investigation of the double layer structure of 1-butyl-3-methylimidazolium thiocyanate at the air-water interface using sum-frequency generation vibrational spectroscopy.

The interfacial structure and adsorption behavior of 1-butyl-3-methylimidazolium thiocyanate ionic liquids (ILs) aqueous solutions were investigated using sum-frequency generation vibrational spectroscopy (SFG-VS) and surface tension measurements. Polarization-dependent measurements revealed a dramatic increase in the SFG signal for both CH and CN stretching modes with increasing ILs concentration, reaching a maximum at a mole fraction of 0.01. This concentration dependence was accompanied by a dramatic drop in surface tension. Upon further increasing the concentration, surface tension varied slightly and reached a constant value, while the SFG signal decreased significantly. Quantitative polarization analysis showed that as the bulk concentration increased, the apparent molecular orientation of the SCN- transition dipole at the interface changed from 51° to 46°, and the tilt angle of CH3 group of the butyl chain attached to the imidazole cationic ring changed from 18° to 32°. The decrease in the SFG signal can be explained by the formation of a double layer adsorption structure at the air/water interface. It was also demonstrated that the anions were adsorbed at the interface simultaneously with the cationic group, rather than by successive adsorption as proposed in a previous study. Using the Shereshefsky model, the thermodynamic Gibbs free energy of adsorption deduced from surface tension data was compared with SFG results.

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.

Layer-Ordered Organooxotin Clusters for Extreme-Ultraviolet Photolithography.

Extreme-ultraviolet (EUV) photolithography, which enables the high-throughput production of well-defined patterns with critical dimensions on the scale of several nanometers, is essential for the fabrication of a highly integrated semiconductor. The full exploitation of EUV lithographic techniques necessitates the development of photoresist (PR) materials with both high EUV sensitivity and a long shelf-life. However, despite notable advances, the available library of EUV PR materials remains limited. Here we report EUV PRs capable of forming preorganized layers consisting of ladder-structured tetranuclear stannoxanes. Single-crystal X-ray structure analyses reveal a close interlayer distance of 8.5 Å through interdigitation of the pseudoaxial butyl chains. The developed EUV PR materials exhibit high solubility in organic solvents commonly used in semiconductor processing, enabling the preparation of PR solutions with superior wettability and uniform film-forming ability on Si wafer substrates. These PR solutions also demonstrate notable resistance to hydrolytic decomposition for as long as 1 month, indicating a long shelf-life. Our PR materials enabled negative-tone patterning processes that involved a solubility decrease upon irradiation. The presence of chromophoric ligands makes our PR materials compatible with conventional UV photolithography, through photochemical reactions involving carbonyl units. In addition, e-beam and EUV lithography could produce fine line patterns of our PRs, with critical dimensions of 20 and 15 nm, respectively. Our research showcases the potential of layer-ordered organooxotin clusters for EUV PR applications.

Fluorescence Lifetime Super-Resolution Imaging Unveil the Dynamic Relationship between Mitochondrial Membrane Potential and Cristae Structure Using the Förster Resonance Energy Transfer Strategy.

Mitochondrial cristae, invaginations of the inner mitochondrial membrane (IMM) into the matrix, are the main site for the generation of ATP via oxidative phosphorylation, and mitochondrial membrane potential (MMP). Synchronous study of the dynamic relationship between cristae and MMP is very important for further understanding of mitochondrial function. Due to the lack of suitable IMM probes and imaging techniques, the dynamic relationship between MMP and cristae structure alterations remains poorly understood. We designed a pair of FRET-based molecular probes, with the donor (OR-LA) being rhodamine modified with mitochondrial coenzyme lipoic acid and the acceptor (SiR-BA) being silicon-rhodamine modified with a butyl chain, for simultaneous dynamic monitoring of mitochondrial cristae structure and MMP. The FRET process of the molecular pair in mitochondria is regulated by MMP, enabling more precise visualization of MMP through fluorescence intensity ratio and fluorescence lifetime. By combining FRET with FLIM super-resolution imaging technology, we achieved simultaneous dynamic monitoring of mitochondrial cristae structure and MMP, revealing that during the decline of MMP, there is a progression involving cristae dilation, fragmentation, mitochondrial vacuolization, and eventual rupture. Significantly, we successfully observed that the rapid decrease in MMP at the site of mitochondrial membrane rupture may be a critical factor in mitochondrial fragmentation. These data collectively reveal the dynamic relationship between cristae structural alterations and MMP decline, laying a foundation for further investigation into cellular energy regulation mechanisms and therapeutic strategies for mitochondria-related diseases.

Synthesis of poly(ionic liquid-OH) mediated deacetylated chitin and its hydrogels: A study on their applications in controlled release of paracetamol and urea

Due to the biodegradable and biocompatible nature of chitin and chitosan, they are extensively used in the synthesis of hydrogels for various applications. In this work, deacetylation of chitin is carried out with alkaline poly(dimethyldiallylammonium-hydroxide) that gave a higher amount of water-soluble chitin (with 84 % of the degree of deacetylation = chitosan0.84) compared to deacetylation using NaOH. The water-soluble chitosan0.84 is used as intercalating chains for the preparation of acrylic acid and vinylimidazole-based hydrogels. The quaternization of imidazole groups is done with 1,ω-dibromoalkanes, which sets off the crosslinking in the above polymer network. A set of three chitosan0.84 intercalated hydrogels, namely Cs-C4-hydrogel, Cs-C5-hydrogel, and Cs-C10-hydrogel are prepared bearing butyl, pentyl, and decyl chains as respective crosslinkers. The swell ratios of these intercalated hydrogels are compared with those of non-intercalated hydrogels (C4-hydrogel, C5-hydrogel, and C10-hydrogel). Chitosan0.84 intercalated Cs-C10-hydrogel has excellent swelling properties (2330 % swelling ratio) among six synthesized hydrogels. SEM analysis reveals that decyl crosslinker-bearing hydrogels are highly porous. The multi-functionality of Cs-C10-hydrogel and C10-hydrogel is explored towards -the controlled release of paracetamol/urea, and methyleneblue dye absorption. These studies disclose that chitosan0.84 intercalated hydrogels are showing superior-swelling behavior, high paracetamol/urea loading capacities and better dye entrapment than their non-intercalated counterparts.

Mesomorphism of imidazolium-based fluorinated ionic liquids

Ionic liquid crystals have received increasing interest due to their positional and/or orientational order as well as the freedom in molecular motions that arise from the formation of mesophases between solid and liquid. While phase changes of non-fluorinated ionic liquids have been widely reported, there have been few reports on the temperature-dependent phase behavior of fluorinated ionic liquids. Here, we present a series of fluorinated ionic liquids with methylimidazolium cations bearing 1H, 1H, 2H, 2H-perfluoroalkyl chains (butyl, hexyl, and octyl) and halide counterions, and demonstrate their thermotropic mesomorphism. These cations were synthesized under solvent-free conditions, and anion exchange was used to vary the halide counterion. The thermal behavior of the compounds was studied using thermogravimetric analysis and differential scanning calorimetry, revealing both liquid crystalline phases and solid-solid phase transitions. We discovered that the mesomorphic properties of the ionic liquids depend strongly on the length of the perfluoroalkyl pendants. Specifically, ionic liquids with a fluorinated butyl chain showed no mesophase behavior while those with hexyl and octyl fluorinated chains displayed liquid crystalline phases at temperatures above 100 °C. The mesophases were further characterized by polarized optical microscopy and powder X-ray diffraction, highlighting the impact of the fluorinated alkyl chain length.

A Hole-Selective Self-Assembled Monolayer for Both Efficient Perovskite and Organic Solar Cells.

Self-assembled monolayers (SAMs) emerging as promising hole-selective layers (HSLs) are advantageous for facile processability, low cost, and minimal material consumption in the fabrication of both perovskite solar cells (PSCs) and organic solar cells (OSCs). However, owing to the different nature between perovskites and organic semiconductors, few SAMs were reported to effectively accommodate both PSCs and OSCs at the same time. In this regard, a universally applicable SAM that can accommodate both perovskites and organic semiconductors could be desirable for simplifying cell manufacturing, especially from an industrial perspective. In this work, we designed a SAM, TDPA-Cl by introducing chlorinated phenothiazine as the headgroup and linking with anchor phosphonic acid through a butyl chain. The resulting dense SAM was carefully characterized in terms of molecular bonding, surface morphology, and packing density, and its functions in OSCs and PSCs were discussed from the aspects of interactions with the absorber layer, energy level alignment, and charge-selective dipoles. The PM6:Y6-based OSCs with TDPA-Cl SAM as the HSL showed a superior performance to those with PEDOT:PSS. Furthermore, the universality was proved with an efficiency of 17.4% in the D18:Y6 system. In PSCs, the TDPA-Cl-based devices delivered a better performance of 22.4% than the PTAA-based devices (20.8%) with improved processability and reproducibility. This work represents a SAM with reasonably good compromise between the differing requirements of OSCs and PSCs.

Crystalline bilayer formation in homoleptic low-spin Fe(II) compounds with alkyl chain substituents.

A series of asymmetric, homoleptic Fe(II) compounds based on the facially-binding tridentate ligand N-methyl-1,1-di(pyridin-2-yl)Cn-amine (LCn) (Cn = butyl, hexyl, octyl, decyl, dodecyl, tetradecyl and hexadecyl alkyl chains) with formula [FeII(LCn)2](X)2·solvate, where n = 4, 14 and X = BF4 (1C4 and 1C14) or n = 6, 8, 10, 12, 16 and X = CF3SO3 (1C6-1C12 and 1C16), are reported. Complexes 1C6 to 1C16 pack in crystalline bilayers in the solid state, forming hydrophobic and hydrophilic regions between adjacent layers of complexes. The combination of short Fe-N bond distances (∼2.00 Å) and SQUID magnetic susceptibility measurements show that the complexes are in the low-spin state across all measured temperature ranges. Differential scanning calorimetry confirmed phase transitions occur in compounds 1C6, 1C12, 1C14 and 1C16 upon heating from room temperature. The lack of any spin transitions and thermal stability conferred by thermogravimetric analysis over this temperature range suggest that these transitions are crystallographic in nature. 1H NMR studies show that the low-spin Fe(II) centres undergo partial conversion to paramagnetic species in solution. UV-vis spectroscopy in a range of common organic solvents show that the central Fe ions remain in the +2 oxidation state, suggesting that the increase in magnetic susceptibility in solution is likely due to partial spin-crossover, or due to speciation, in which a proportion of the compounds are high-spin Fe(II) complexes.

Polymorph transformation in a mixed-stacking nickel-dithiolene complex with the derivative of 4,4'-bipyridinium.

In this study, two polymorphs of the [1,1'-dibutyl-4,4'-bipyridinium][Ni(mnt)2] salt (1) were synthesized. The dark-green polymorph (designated as 1-g) was prepared under ambient conditions by the rapid precipitation method in aqueous solutions. Subsequently, the red polymorph (labeled as 1-r) was obtained by subjecting 1-g to ultrasonication in MeOH at room temperature. Microanalysis, infrared spectroscopy, thermogravimetry (TG), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD) techniques were used to characterize the two polymorphs. Both 1-g and 1-r exhibit structural phase transitions: a reversible phase transition at ∼403 K (∼268 K) upon heating and 384 K (∼252 K) upon cooling for 1-g (1-r) within the temperature range below 473 K. Interestingly, on heating 1-r to 523 K, an irreversible phase transition occurred at about 494 K, resulting in the conversion of 1-r into 1-g. Relative to 1-r, 1-g represents a thermodynamically metastable phase wherein numerous high-energy conformations in butyl chains of cations are confined within the lattice owing to quick precipitation or rapid annealing from higher temperatures. Through variable-temperature single crystal and powder X-ray diffractions, UV-visible spectroscopy, dielectric spectroscopy, and DSC analyses, this study delves into the mechanism underlying phase transitions for each polymorph and the manual transformation between 1-g and 1-r as well.

Versatile Neuromorphic Modulation and Biosensing based on N-type Small-molecule Organic Mixed Ionic-Electronic Conductors.

The ion/chemical-based modulation feature of organic mixed ionic-electronic conductors (OMIECs) are critical to advancing next generation bio-integrated neuromorphic hardware. Despite achievements with polymeric OMIECs in organic electrochemical neuronal synapse (OENS). However, small molecule OMIECs based OENS has not yet been realized. Here, for the first time, we demonstrate an effective materials design concept of combining n-type fused all-acceptor small molecule OMIECs with subtle side chain optimization that enables robustly and flexibly modulating versatile synaptic behavior and sensing neurotransmitter in solid or aqueous electrolyte, operating in accumulation modes. By judicious tuning the ending side chains, the linear oligoether and butyl chain derivative gNR-Bu exhibits higher recognition accuracy for a model artificial neural network (ANN) simulation, higher steady conductance states and more outstanding ambient stability, which is superior to the state-of-art n-type OMIECs based OENS. These superior artificial synapse characteristics of gNR-Bu can be attributed to its higher crystallinity with stronger ion bonding capacities. More impressively, we unprecedentedly realized n-type small-molecule OMIECs based OENS as a neuromorphic biosensor enabling to respond synaptic communication signals of dopamine even at sub-μM level in aqueous electrolyte. This work may open a new path of small-molecule ion-electron conductors for next-generation ANN and bioelectronics.

Versatile Neuromorphic Modulation and Biosensing based on N‐type Small‐molecule Organic Mixed Ionic‐Electronic Conductors

AbstractThe ion/chemical‐based modulation feature of organic mixed ionic‐electronic conductors (OMIECs) are critical to advancing next generation bio‐integrated neuromorphic hardware. Despite achievements with polymeric OMIECs in organic electrochemical neuronal synapse (OENS). However, small molecule OMIECs based OENS has not yet been realized. Here, for the first time, we demonstrate an effective materials design concept of combining n‐type fused all‐acceptor small molecule OMIECs with subtle side chain optimization that enables robustly and flexibly modulating versatile synaptic behavior and sensing neurotransmitter in solid or aqueous electrolyte, operating in accumulation modes. By judicious tuning the ending side chains, the linear oligoether and butyl chain derivative gNR‐Bu exhibits higher recognition accuracy for a model artificial neural network (ANN) simulation, higher steady conductance states and more outstanding ambient stability, which is superior to the state‐of‐art n‐type OMIECs based OENS. These superior artificial synapse characteristics of gNR‐Bu can be attributed to its higher crystallinity with stronger ion bonding capacities. More impressively, we unprecedentedly realized n‐type small‐molecule OMIECs based OENS as a neuromorphic biosensor enabling to respond synaptic communication signals of dopamine even at sub‐μM level in aqueous electrolyte. This work may open a new path of small‐molecule ion‐electron conductors for next‐generation ANN and bioelectronics.

Microstructure of ionic liquids mixed with water on the charged graphene surface: A coarse-grained molecular dynamics simulation study

Ionic liquids (ILs) inevitably absorb a certain amount of moisture from the air during the synthesis and utilization processes. The presence of water can have a significant impact on the interfacial property of ILs on charged graphene surfaces. This study employs molecular dynamic (MD) simulation to explore the microstructure of ILs [BMIM + ][BF4-] (1-butyl-3-methylimidazolium tetrafluoroborate) mixed with water on charged surfaces and examine the existence of water and surface charge density on interfacial behaviors. The result shows that coarse particles accumulate on the charged surface as the charge density of the surface increases. More anionic particles A (anions [BF4-]) are absorbed to the positively charged surface, resulting in a more obvious layered structure between anionic and cationic particles. However, coarse particles C3 (Butyl chain in cationic group) rotate due to the repulsion from co-ions and move slightly away from the upper negatively charged surface. Besides, due to the strong interaction from the anionic particles, water molecules distribute asymmetrically on the upper and lower surfaces with different charges, and as the charge density increases, the peak location of number density moves closer to the surface. The results provide a molecular-level understanding of the effect of surface water and charge density on the interfacial microstructure of ILs on charged surfaces.

Purification of linearized template plasmid DNA decreases double-stranded RNA formation during IVT reaction.

After the COVID-19 pandemic, messenger RNA (mRNA) has revolutionized traditional vaccine manufacturing. With the increasing number of RNA-based therapeutics, valuable new scientific insights into these molecules have emerged. One fascinating area of study is the formation of double-stranded RNA (dsRNA) during in vitro transcription (IVT) which is considered a significant impurity, as it has been identified as a major trigger in the cellular immune response pathway. Therefore, there is a growing importance placed to develop and optimize purification processes for the removal of this by-product. Traditionally, efforts have primarily focused on mRNA purification after IVT through chromatographic separations, with anion exchange and reverse phase chromatography emerging as effective tools for this purpose. However, to the best of our knowledge, the influence and significance of the quality of the linearized plasmid have not been thoroughly investigated. Plasmids production involves the growth of bacterial cultures, bacterial harvesting and lysis, and multiple filtration steps for plasmid DNA purification. The inherent complexity of these molecules, along with the multitude of purification steps involved in their processing, including the subsequent linearization and the less-developed purification techniques for linearized plasmids, often result in inconsistent batches with limited control over by-products such as dsRNA. This study aims to demonstrate how the purification process employed for linearized plasmids can impact the formation of dsRNA. Several techniques for the purification of linearized plasmids based on both, resin filtration and chromatographic separations, have been studied. As a result of that, we have optimized a chromatographic method for purifying linearized plasmids using monolithic columns with C4 chemistry (butyl chains located in the surface of the particles), which has proven successful for mRNAs of various sizes. This chromatographic separation facilitates the generation of homogeneous linearized plasmids, leading to mRNA batches with lower levels of dsRNA during subsequent IVT processes. This finding reveals that dsRNA formation is influenced not only by RNA polymerase and IVT conditions but also by the quality of the linearized template. The results suggest that plasmid impurities may contribute to the production of dsRNA by providing additional templates that can be transcribed into sequences that anneal with the mRNA molecules. This highlights the importance of considering the quality of plasmid purification in relation to dsRNA generation during transcription. Further investigation is needed to fully understand the mechanisms and implications of plasmid-derived dsRNA. This discovery could shift the focus in mRNA vaccine production, placing more emphasis on the purification of linearized plasmids and potentially saving, in some instances, a purification step for mRNA following IVT.

The microwave spectra of the conformers of n-butyl nitrate

The microwave spectrum of n-butyl nitrate was recorded in the 5 to 20 GHz frequency range using broadband chirp and narrowband pulse excitation molecular jet Fourier transform microwave spectrometers. A quantum chemistry structural analysis yielded thirteen stable conformers. Among them, the five most energetically stable conformers were observed in the experimental spectra. The most stable conformer features a butyl chain with an anti-gauche-anti conformation (AGA) where the γ-carbon atom is about 64° out of the nitrate plane. For this conformer, spectra of all 13C and 15N minor isotopologues could be measured. The conformer with a straight butyl chain (AAA), and three other conformers (GAA, GGA, and AGG) were also observed. Accurate rotational constants, centrifugal distortion constants, and 14N nuclear quadrupole coupling constants could be deduced and compared to the theoretical values.

Molecular organization and molecular order of two rod-like smectogens in mesophases

ABSTRACT Structurally simple two rod-like mesogens with a three-ring core consisting of biphenyl and phenyl rings are synthesised to investigate the mesophase properties, molecular organisation and the orientational order parameter. In mesogen-1, a dodecyloxy terminal chain is present on the biphenyl ring while the phenyl ring is free from substituent. For mesogen-2, in addition to the dodecyloxy chain, the butyl chain is placed on the phenyl ring. The Hot-stage optical polarising microscopy (HOPM) and differential scanning calorimetry (DSC) measurements show smectic A (SmA), smectic B (SmB), and crystal E (CryE) phases for mesogen-1 and SmA, smectic C (SmC) and smectic F (SmF) phases for mesogen-2. The presence of smectic mesophases is established by X-ray Diffraction (XRD). 1D and 2D 13C solid-state NMR experiments are performed in smectic mesophases to find the orientational order parameters of the phenyl rings of the core. The main order parameter (Szz) of the mesogens in the SmB and SmF phase is in the range of 0.87–0.93. The excellent spectral resolution noticed in 13C NMR spectra in the SmB mesophase (mesogen-1) indicates that the internal rotations of the molecules along the long axis are primarily unhindered.

Supercritical Fluid Nanospray Mass Spectrometry: II. Effects on Ionization.

Nanospraying supercritical fluids coupled to a mass spectrometer (nSF-MS) using a 90% supercritical fluid CO2 carrier (sCO2) has shown an enhanced desolvation compared to traditional liquid eluents. Capillaries of 25, 50, and 75 μm internal diameter (i.d.) with pulled emitter tips provided high MS detection sensitivity. Presented here is an evaluation of the effect of proton affinity, hydrophobicity, and nanoemitter tip size on the nSF-MS signal. This was done using a set of primary, secondary, tertiary, and quaternary amines with butyl, hexyl, octyl, and decyl chains as analytes. Each amine class was analyzed individually to evaluate hydrophobicity and proton affinity effects on signal intensity. The system has shown a mass sensitive detection on a linear dynamic range of 0.1-100 μM. Results indicate that hydrophobicity has a larger effect on the signal response than proton affinity. Nanospraying a mixture of all amine classes using the 75 μm emitter has shown a quaternary amine signal not suppressed by competing analytes. Competing ionization was observed for primary, secondary, and tertiary amines. The 75 and 50 μm emitters demonstrated increased signal with increasing hydrophobicity. Surprisingly, the 25 μm i.d. emitter yielded a signal decrease as the alkyl chain length increased, contrary to conventional understanding. Nanospraying the evaporative fluid in a sub-500 nm emitter likely resulted in differences in the ionization mechanism. Results suggest that 90% sCO2 with 9.99% methanol and 0.01% formic acid yielded fast desolvation, high ionization efficiency, and low matrix effect, which could benefit complex biological matrix analysis.

In-depth unveiling the interfacial adsorption mechanism of triazine derivatives as corrosion inhibitors for carbon steel in carbon dioxide saturated oilfield produced water

In this work, two triazine derivatives (BTT-1 and BTT-2) were synthesized by the simple one-step condensation of three components and used as high-efficient corrosion inhibitors to deal with the corrosion issue of carbon steel (CS) in petroleum industry. Electrochemical tests indicate that both BTT-1 and BTT-2 present superior inhibition performance with the inhibition efficiency of 97.9 % and 98.4 % at a low concentration of 0.18 mM, respectively. Quantum chemical calculations reveal that compared to BTT-1 molecule with a butyl chain, the introduction of benzyl group endows BTT-2 molecule with more adsorption sites, which favors the adsorption of BTT-2 molecule on CS surface. Furthermore, the GFN-xTB calculations demonstrate that BTT-1 and BTT-2 could adsorb on CS surface through the formation of Fe−N and Fe−S bonds. Compared to BTT-1, BTT-2 exhibits stronger adsorption on CS surface by forming more and shorter bonds with a more negative adsorption energy, which accounts for the better inhibitive performance of BTT-2.

Ionic liquid mixtures as energy storage materials: a preliminary and comparative study based on thermal storage density.

Fifteen equimolar binary mixtures are synthesized and thermophysically evaluated in this study. These mixtures are derived from six ionic liquids (ILs) based on methylimidazolium and 2,3-dimethylimidazolium cations with butyl chains. The objective is to compare and elucidate the impact of small structural changes on the thermal properties. The preliminary results are compared to previously obtained results with mixtures containing longer eight-carbon chains. The study demonstrates that certain mixtures exhibit an increase in their heat capacity. Additionally, due to their higher densities, these mixtures achieve a thermal storage density equivalent to that of mixtures with longer chains. Moreover, their thermal storage density surpasses that of some conventional materials commonly used for energy storage.

Designing Functionally Substituted Pyridine-Carbohydrazides for Potent Antibacterial and Devouring Antifungal Effect on Multidrug Resistant (MDR) Strains.

The emergence of multidrug-resistant (MDR) pathogens and the gradual depletion of available antibiotics have exacerbated the need for novel antimicrobial agents with minimal toxicity. Herein, we report functionally substituted pyridine carbohydrazide with remarkable antimicrobial effect on multi-drug resistant strains. In the series, compound 6 had potent activity against four MDR strains of Candida spp., with minimum inhibitory concentration (MIC) values being in the range of 16-24 µg/mL and percentage inhibition up to 92.57%, which was exceptional when compared to broad-spectrum antifungal drug fluconazole (MIC = 20 µg/mL, 81.88% inhibition). Substitution of the octyl chain in 6 with a shorter butyl chain resulted in a significant anti-bacterial effect of 4 against Pseudomonas aeruginosa (ATCC 27853), the MIC value being 2-fold superior to the standard combination of ampicillin/cloxacillin. Time-kill kinetics assays were used to discern the efficacy and pharmacodynamics of the potent compounds. Further, hemolysis tests confirmed that both compounds had better safety profiles than the standard drugs. Besides, molecular docking simulations were used to further explore their mode of interaction with target proteins. Overall results suggest that these compounds have the potential to become promising antimicrobial drugs against MDR strains.

Divergent Behavior in the Chemistry of Metal‐Bis(dithiolene) Complexes Appended with Peripheral Aliphatic Butyl Chains

AbstractMetal‐bis(dithiolene) complexes derived from Ni(II), Co(II), Pd(II), Pt(II) and Au(III), bearing butyl aliphatic chains have been synthesized, and fully characterized by a variety of spectroscopic techniques including NMR, UV‐vis, IR, HRMS, CV, and X‐ray diffraction studies. This comparative study made possible to establish that the Co(II) species appear to be dimeric in the solid state as well as in solution. On the other hand, the coordination complexes based on Ni(II), Pd(II), Pt(II) and Au(III), feature a monomeric structure in both solution and solid state. These metal‐bis(dithiolene) complexes are remarkably stable in solution and, in stark contrast to precedents in the literature, they retain their square planar geometry even in presence of pyridine derivatives reported for their apical binding on metal‐bis(dithiolene) complexes.