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A trifluoromethyl group substituted C–C bonded nitrogen rich energetic material 3-(3-nitro-1H-pyrazol-4-yl)-5-(trifluoromethyl)-1,2,4-oxadiazole (4), its hydroxyl amine (5) and 3,6,7-triamino-7H-[1,2,4]triazolo[4,3-b][1,2,4]triazol-2-ium (6) salts and hydrazinium 5-(3-nitro-1H-pyrazol-4-yl)-3-(trifluoromethyl)-1,2,4-triazol-1-ide (7) were synthesized and fully characterized using infrared spectroscopy (IR), multinuclear magnetic resonance (NMR) spectroscopy (1H, 13C, and 19F), high-resolution mass spectrometry (HRMS), elemental analysis (EA) and differential scanning calorimetry (DSC) studies. Furthermore, compounds 4 and 7 were confirmed using single-crystal X-ray diffraction studies (SC-XRD). All compounds possess good density (1.70–1.80 g cm−3), detonation velocity (6432–7144 m s−1), pressure (16.38–20.31 GPa), and thermal stability (>170 °C). They are insensitive towards mechanical stimuli, impact (IS > 35 J) and friction (FS > 288 N). Overall, due to their balanced performance, these compounds can be a better replacement for presently used explosives such as trinitrotoluene (TNT). [ABSTRACT FROM AUTHOR]

In an attempt to cultivate energy‐stability balance, a series of nitrogen and oxygen‐rich high energy density materials were synthesized based on N‐substituted 4‐hydroxy‐3,5‐dinitropyrazole and methylene‐linked N‐amino‐1,2,4‐bridges. The hydroxy substituent contributed to oxygen content, hydrogen bonding, and tunability via salt formation. On the other hand, the triazole bridge delivered high nitrogen content and thermal stability. All the synthesized compounds were characterized with multinuclear NMR, FTIR, HRMS, and elemental analysis, and their physicochemical and energetic properties were analyzed. Energetic materials 1–5 showed high detonation performance and adequate overall stabilities. Compound 1 exhibited higher density (1.84 g/cm3) and detonation performance (Dv = 8103 m/s, P = 26.9 GPa) in comparison to its reported amino derivative. [ABSTRACT FROM AUTHOR]

Heat‐resistant explosives play a vital role in indispensable applications. For this, we have synthesized a novel, three‐dimensional, solvent‐free energetic metal−organic framework (EMOF) potassium 3,5‐dinitro‐6‐oxo‐1,6‐dihydropyrazin‐2‐olate (KDNODP) straightforwardly. The synthesized EMOF was characterized through IR, NMR spectroscopy, elemental analysis, and differential scanning calorimetry studies. Furthermore, single‐crystal X‐ray diffraction provided a complete description of KDNODP. It exhibits a three‐dimensional EMOF structure with remarkably balanced properties such as high density (2.11 g cm−3), excellent thermal stability (291 °C), good detonation performance (8127 m s−1 and 26.94 GPa) and low mechanical sensitivity (IS=35 J; FS=360 N) than the commonly used heat‐resistant explosives HNS (density=1.74 g cm−3; VOD=7164 m s−1, DP=21.65 GPa, IS=5 J) as well as the similar reported energetic potassium MOFs. To gain insights into the packing and intermolecular interactions, the Hirshfeld surface and a 2D fingerprint analysis were examined. Additionally, scanning electron microscopy was used to investigate the particle size and morphological characteristics of KDNODP. These outcomes highlight a successful method for creating 3D EMOF based on a six‐membered heterocycle as a potential heat‐resistant energetic material. [ABSTRACT FROM AUTHOR]

This article presents a new method for synthesizing polysubstituted imidazoles, which are compounds with various pharmaceutical and biological applications. The authors optimized the reaction conditions using iron catalysis and oxygen as the sole oxidant, resulting in high yields of the desired products. The protocol provides a straightforward and efficient method for synthesizing polysubstituted imidazole compounds using easily available starting materials. The article also includes chemical data for various compounds, including their yields, physical properties, and nuclear magnetic resonance (NMR) spectra. [Extracted from the article]

Various types of materials have been explored in the pursuit of high energy density materials (HEDMs) that have balanced energy and stability. Among them, energetic salts show numerous advantages, such as lower vapor pressures, high physical stabilities, and the opportunity for favorable tuning by careful selection of cations/anions. Nitrogen-rich bases are generally used as cations for energetic salt formation. While the synthesis of salts with larger cations lowers the sensitivity, smaller cations aid better energetic performance. A combination of both in the same ionic moieties might help in the formation of a superior explosive. In this work, a facile route for the synthesis of mixed dicationic energetic salts based on 1-((1H-tetrazol-5-yl)methyl)-3,5-dinitro-1H-pyrazol-4-ol (compound 1) has been explored by various combinations of bigger and smaller cations (compounds 4-10). All the synthesized energetic salts showed high positive heats of formation, energetic performance comparable to TATB, excellent stability towards impact and friction, and acceptable thermal stabilities. This improved technique will provide an additional option for fine-tuning the energetic properties of HEDMs and will facilitate in exploring the role of various cations in the overall performance of the energetic compounds. [ABSTRACT FROM AUTHOR]

A three‐component multicomponent approach has been developed at room temperature for the synthesis of 4H‐pyrano[3,2‐c]quinoline‐3‐carbonitriles. The all synthesized products were afforded in short reaction time with excellent yield using BABCO catalyst. The process is proficient with good tolerance of functional groups and well‐explored substrate scope. [ABSTRACT FROM AUTHOR]

Context: Various 7H,7′H-[6,6′-bi[1,2,4]triazolo[4,3-b][1,2,4]triazole]-3,3′,7,7′-tetramine (A) based nitrogen-rich energetic salts were designed and their properties explored. All energetic salts possess relatively high nitrogen content (> 48%), positive heats of formation (> 429 kJ/mol) and stability owing to a significant contribution from fused backbone. The cationic component shows a very high heat of formation (2516 kJ/mol); therefore, it is highly suitable for enthalpy enhancement in new energetic salts. The cation was paired with the energetic anions nitrate (NO3−), perchlorate (ClO4−), dinitromethanide (CH(NO2)2−), trinitromethanide (C(NO2)3−), nitroamide (NHNO2−), and dinitroamide (N(NO2)2−) to improve oxygen balance and detonation performance. Designed salts show moderate detonation velocities (7.9–8.7 km/s) and pressures (23.8 − 33.1 GPa). The distribution of frontier molecular orbitals, molecular electrostatic surface potentials, QTAIM topological properties, and noncovalent interactions of designed salts were simulated to understand the electronic structures, charge distribution in molecules, hydrogen bonding, and other nonbond interactions. The predicted safety factor (SF) and impact sensitivity (H50) of designed salts suggest their insensitivity to mechanical stimuli. This work explored the 7H,7′H-[6,6′-bi[1,2,4]triazolo[4,3-b][1,2,4]triazole]-3,3′,7,7′-tetramine as a suitable cationic component which could be promising and serve exemplarily in energetic materials. Methods: The optimization and energy calculations of all the designed compounds were carried out at the B3LYP/6–311 + + G(d,p) and M06-2X/def2-TZVPP levels, utilizing the Gaussian software package. The molecular surface electrostatic potential, quantum theory of atoms in molecules (QTAIM), reduced density gradient (RDG), and noncovalent interaction (NCI) analysis were performed by employing Multiwfn software. The EXPLO5 (v 7.01) thermochemical code and PILEM web application were used to predict the detonation properties. [ABSTRACT FROM AUTHOR]

A series of five and six‐membered C‐C bonded energetic materials (2–7) based on a combination of imidazole‐triazine and triazole‐triazine backbones were designed, synthesized, and characterized using NMR, IR, Mass spectrometry, and TGA‐DSC studies. Further, the structure of compound 4 was supported by single‐crystal X‐ray analysis. All the newly synthesized energetic compounds exhibit good density, excellent thermal stability, good detonation performance, and low mechanical sensitivity toward impact and friction. Among all, the nitrate salt 4 exhibits balanced properties, including high density (1.80 g cm−3), excellent thermal stability (254°C), good detonation velocity (8178 m s−1), and low sensitivity towards impact and friction. The facile synthetic feasibility, thermal stability, energetic performance, and insensitivity of all the molecules suggest they can be used as an insensitive secondary explosive in various defense and civilian applications. [ABSTRACT FROM AUTHOR]

A Fluorescence-Linked Immunosorbent Assay (FLISA) targeting β-cross-sheet α-synuclein protein, a crucial marker in Parkinson’s Disease (PD), was assessed using in vitro assay with a rotenone-induced PD cellular model. The study aimed to evaluate FLISA’s applicability with the inhouse developed labelled polyclonal antibody (pAb). Results are promising the competitive assay successfully distinguished misfolded α-synuclein in SH-SY5Y cells. Quantitative analysis revealed a direct correlation between competitive antigen concentration and decreased fluorescence, showcasing FLISA’s sensitivity. Controls exhibited maximal fluorescence, confirming the absence of misfolded proteins, while rotenoneexposed cells displayed reduced fluorescence, suggesting their presence. This approach enhances PD understanding and supports potential interventions. [ABSTRACT FROM AUTHOR]

A series of nitrogen-rich fused energetic materials were synthesized from commercially available inexpensive starting materials and fully characterized using 1H and 13C NMR, IR spectroscopy, elemental analysis, and DSC. The structure of zwitterionic compound 2 was supported by SCXRD data. Among all, 3 and 4 possess excellent detonation velocity (8956 and 9163 m s−1) and are insensitive towards friction (>360 N) and impact (10 J), having moderate to excellent thermal stability (171–262 °C). It is worth mentioning that the zwitterionic fused pyrazolo-triazole compound 2 and its energetic salts offer remarkable performance as new-generation thermally stable energetic materials. [ABSTRACT FROM AUTHOR]

In energetic materials research, energetic coordination compounds (ECCs) have received much attention due to their high thermal stability and insensitivity to mechanical stimuli. The energetic characteristics of ECCs can be modified by combining various metal cations, potent anions, and ligands. In this study, we have synthesized two energetic ligands, 5-(4-nitro-1H-pyrazol-3-yl)-1H-1,2,4-triazol-3-amine (NPTA) and (Z)-N-(5-(4-nitro-1H-pyrazol-3-yl)-2,4-dihydro-3H-1,2,4-triazol-3-ylidene)nitramide (NPTN), from a commercially viable starting material and reacted them with nitrate salts of various 3d metals (e.g., Ni, Co, Zn) to obtain six new ECCs, [Ni(NPTA)(H2O)3]2·2NO3 (1), [Co(NPTA)(H2O)3]2·2NO3 (2), [Zn(NPTA)(H2O)3]2·2NO3 (3), [Ni(NPTN)(H2O)3]2 (4), [Co(NPTN)(H2O)3]2 (5), and [Zn(NPTN)(H2O)3]2 (6) under ambient conditions. All the newly prepared ECCs were characterised through PXRD, IR, SEM, and TGA-DSC analysis. Furthermore, single crystal analysis proved that 1–6 are dimeric complexes. Moreover, 1–6 show excellent density ranges from 1.94 to 2.06 g cm−3 and remarkable thermal stability (216–352 °C), and are highly insensitive towards impact (>40 J) and friction (>360 N), describing their potential as high performing energetic materials. All the ECCs revealed good enthalpy of combustion (−6.3 to −9.94 kJ g−1). Additionally, the Hirshfeld surface and 2D fingerprint analysis were used to understand the close contact of atoms within the molecules. High crystal densities, thermal stabilities and low sensitivities make the synthesized ECCs interesting for further studies and potential applications as safe high-energy dense materials. [ABSTRACT FROM AUTHOR]

4H,8H-bis[1,2,5]oxadiazolo[3,4-b:3',4'-e]pyrazine (bis-oxadiazolo-pyrazine) represents a versatile CHNO backbone for the design of energetic materials. In this paper, we report a comprehensive computational study using density functional theory to improve detonation properties of this CHNO backbone by introducing pyrazine rings, nitro groups, and N-oxide functionalities. The heat of formation, oxygen balance, density, and detonation properties of a series of furazan-pyrazine fused ring derivatives are computed. Their sensitivity and stability has been correlated with bandgap (ΔELUMO-HOMO), maximum heat of detonation (Q), and impact energy (h50). Introduction of –NO2 and N–oxide on the parent furazan-pyrazine fused ring derivatives is favorable for improving the heat of formation, oxygen balance and density. The heat of formation varies between 464.46 and 1043.57 kJ/mol, and the densities range from 1.75 to 2.01 g/cm3. The positive heat of formation and high densities achieved good detonation velocities (6.74 to 9.61 km/s) and pressures (19.96–43.65 GPa). Among the bis-oxadiazolo-pyrazine derivatives, P5, P6, Q5, Q6, R4, R5, and R6 are fascinating due to their high detonation performances, have calculated detonation velocities and pressures above 9.30 km/s and 40.0 GPa, respectively. Some furazan-pyrazine fused ring derivatives reveal good performance parameters with reasonable stability, confirming them as potential energetic compounds relative to RDX and HMX. [ABSTRACT FROM AUTHOR]

A library of chalco-pyrene linked 1,2,3-triazole hybrids containing both electron-donating and withdrawing groups were synthesized through CuAAC click chemistry and fully characterized by FTIR, 1H-NMR, 13C-NMR, and HRMS data. The photophysical and DFT properties were comparatively investigated for the synthesized chalcone-linked 1,2,3-triazole. A comparative study revealed that the chalco-pyrene linked 1,2,3-triazoles are fluorescent (excimer emission in a range of 510–515 nm), while, simple chalcone linked 1,2,3-triazole (8) remained non-fluorescent due to the absence of chromophore pyrene. The emission intensity of chalco-pyrene linked alkyne 4 and 1,2,3-triazole substituted with NO2 group i.e. 6f (1-{3-[1-(4-Nitro-benzyl)-1H-[1,2,3]triazol-4-ylmethoxy]-phenyl}-3-pyren-1-yl-propenone) is less as compared to rest of the chalco-pyrene linked 1,2,3-triazoles. The DFT study result supported and fine tuned to propose 6f as a promising semiconducting compound (least band gap of 2.95 eV and highest electrophilicity index of 6.11 eV) due to the strong electron-withdrawing nature of the –NO2 group. [ABSTRACT FROM AUTHOR]

A series of gem-dinitromethyl substituted zwitterionic C – C bonded azole based energetic materials (3–8) were designed, synthesized, and characterized through NMR, IR, EA, and DSC studies. Further, the structure of 5 was confirmed with SCXRD and those of 6 and 8 with 15N NMR. All the newly synthesized energetic molecules exhibited higher density, good thermal stability, excellent detonation performance, and low mechanical sensitivity to external stimuli such as impact and friction. Among all, compounds 6 and 7 may serve as ideal secondary high energy density materials due to their remarkable thermal decomposition (200 °C and 186 °C), insensitivity to impact (>30 J), velocity of detonation (9248 m s−1 and 8861 m s−1) and pressure (32.7 GPa and 32.1 GPa). Additionally, the melting and decomposition temperatures of 3 (Tm = 92 °C, Td = 242 °C) indicate that it can be used as a melt-cast explosive. The novelty, synthetic feasibility, and energetic performance of all the molecules suggest that they can be used as potential secondary explosives in defence and civilian fields. [ABSTRACT FROM AUTHOR]

A carbamate-linked-bistriazole (5) was prepared by click reaction of diethynyl 1,3-phenylenedicarbamate (2) and phenyl azide derivative (4) in DMF/H2O using copper sulfate and sodium ascorbate as a catalyst at room temperature for fluoride ion sensing. The structural analysis of synthesized compound was done by using 1HNMR, 13C NMR, FTIR and HRMS. The sensing behavior of carbamate-linked-bistriazole (5) was examined by 1HNMR, UV–vis and fluorescence study. NMR titration study suggested the participation of triazole, amide and aromatic protons in binding of fluoride ion. UV–visible study established the 1:1 complexation ratio between sensor 5 and F– ion with stability constant K of 2.64 × 104 M−1 and detection limit in µM range (9.372 µM). Further, fluorescence titration for 5 (9.2 × 10−6 M) with fluoride ions exhibited an emission quenching at 424 nm along with small bathochromic shift. Density functional theory (DFT) calculations also confirmed interaction mechanism in 5a-F– complex established by, UV–visible, 1H NMR and fluorescence studies. [ABSTRACT FROM AUTHOR]

Synthetic cell–cell interaction systems can be useful for understanding multicellular communities or for screening binding molecules. We adapt a previously characterized set of synthetic cognate nanobody–antigen pairs to a yeast–bacteria coincubation format and use flow cytometry to evaluate cell–cell interactions mediated by binding between surface‐displayed molecules. We further use fluorescence‐activated cell sorting to enrich a specific yeast‐displayed nanobody within a mixed yeast‐display population. Finally, we demonstrate that this system supports the characterization of a therapeutically relevant nanobody–antigen interaction: a previously discovered nanobody that binds to the intimin protein expressed on the surface of enterohemorrhagic Escherichia coli. Overall, our findings indicate that the yeast–bacteria format supports efficient evaluation of ligand–target interactions. With further development, this format may facilitate systematic characterization and high‐throughput discovery of bacterial surface‐binding molecules. [ABSTRACT FROM AUTHOR]

Various thermally stable energetic materials with high nitrogen content, low sensitivity and better detonation performance were synthesized. The versatile functionalization of 1,2,4-triazine involving the introduction of oxadiazole and tetrazole is discussed. All the compounds were fully characterized using IR, multinuclear NMR spectroscopy, elemental analysis, and high-resolution mass spectrometry. Compounds 2, 3, 9 and 12 were further verified using single-crystal X-ray analysis. Compound 9 can be considered a melt-cast explosive due to its lower onset melting temperature (112 °C). The detonation velocity, pressure, density, and heat of formation of all the synthesized compounds range between 7056 and 8212 m s−1, 17.57 and 23.78 GPa, 1.70 and 1.81 g cm−1, and 43 and 644 kJ mol−1, respectively. Due to the high nitrogen percentage (53 to >72%), these molecules can be used in car airbag applications. Due to the high thermal stability (>220 °C) and lower sensitivity, these compounds can be potentially used as high-performing thermally stable secondary energetic materials. [ABSTRACT FROM AUTHOR]

The development of small molecule based drugs as an antimicrobial agent is an important area of research nowadays. In the present work, two new molecular entities based on dialkylated erythrosin B has been synthesized via Arbuzov type of rearrangement using dialkyl sulphite as a reagent in the presence of Et3N. Ethyl and methyl based dialkylated derivatives of erythrosin B were characterized using 1H NMR, 13C NMR and HRMS data. Keeping in mind the biological safety of erythrosin B, synthesized derivatives were checked for their antimicrobial activity against the microbial strains Escherichia coli (E.coli). The two were found to be effective against the E. coli with the antimicrobial activity similar to that of Ampicillin. Further, the trend of antimicrobial activity has been supported by DFT data analysis and it was observed that compound, B with low HOMO (–5.93 eV) and LUMO (–3.11 eV) energies is a better antimicrobial agent than compound A. [ABSTRACT FROM AUTHOR]

Energetic materials serve as remarkable fuel/propellants for space shuttles, and their utility in civil and military applications is vast. The emergence of new and powerful energetic materials possessing signature chemical structures such as nitroaromatics and oxygen/nitrogen-rich heterocyclic scaffolds continues to evolve. Nitrogen-rich materials add to the advantage of being "green" energetic materials by eliminating oxidative carbon dioxide released into the atmosphere. Here, we report for the first time a single-step synthesis of nitrogen-rich (5,5′-dinitramino-3,3′-azo-1,3,4-oxadiazole (5) and its energetic salts obtained in quantitative yields from commercially available inexpensive starting materials. Our set of molecules possessed superior energetic properties to those of benchmark explosives HMX, ε-CL-20, and ICM-101. Among these, compound 5 exhibited an exceptional energetic property with a remarkable density of 1.97 g cm−3 at 298 K, high positive heat of formation (405.7 kJ mol−1), high detonation velocity, pressure (9358 m s−1 and 39.1 GPa), good thermal stability (185 °C), and acceptable impact and friction sensitivity (6 J and 160 N). Compound 5 was recognized as a potential less sensitive HEDM with a planar and high symmetry crystal structure. Our effort to assess the toxicity profiles of our compounds against human embryonic kidney cells indicated the compounds are biosafe and nontoxic even at the concentration of 50 μM. Together, our study points to an incredible green, high energetic material with signs of evolving to give next-generation secondary energetic materials in space, civil and military applications. [ABSTRACT FROM AUTHOR]

This work describes a new route to thermally stable energetic materials by connecting different types of energetic moieties (nitropyrazole and polynitrobenzene) with C−C bonds, where the first step involves a Suzuki cross‐coupling reaction between 4‐bromo‐3,5‐dinitro‐1H‐pyrazole and 4‐chlorophenylboronic acid. Further nitration, amination, oxidation, and salt formation reactions on the resulting C−C coupled framework resulted in various thermally stable energetic materials. All the compounds were fully characterized using IR, NMR [1H, 13C{1H}], differential scanning calorimetry (DSC), elemental analysis, and HRMS studies. Compounds 7 and 9 were further characterized by 15N NMR, and compounds 3 and 6 were characterized by single‐crystal X‐ray diffraction studies. Theoretical heats of formation and energetic performance for all the energetic compounds were calculated using Gaussian 09 and EXPLO5 v6.06 programs, respectively. This research introduces a novel method for synthesizing C−C coupled energetic materials that are not accessible by any other routes. [ABSTRACT FROM AUTHOR]

Mixed ligand complexes of transition metal ions Co(II), Ni(II), Cu(II) and Zn(II) were synthesized using bidentate Schiff's base (E)-2-((benzo[d]thiazol-2-yliminomethyl)-6-methoxyphenol (L1), derived from condensation reaction of 2-aminobenzothiazole and 2-hydroxy-3-methoxybenzaldehyde, and 5-Chloro-8-hydroxyquinoline (5CHQ) (L2) as ligands. All the synthesized compounds were characterized using elemental analysis, IR, electronic, 1H and 13C NMR spectra, TGA-DTA and Powder XRD analysis, molar conductivity and magnetic susceptibility measurements. Based on the results obtained all the synthesized complexes are proposed to have tetrahedral geometry. All the synthesized compounds were screened for their antioxidant, antimicrobial, antimalarial, antidibetic, anticancer activities and cytotoxicity study using MTT assay. The complexes are proposed to have potential antimalarial, antidibetic and anticancer activities. [ABSTRACT FROM AUTHOR]

A simple copper catalyzed "one‐pot" process has been developed for synthesis of polysubstituted imidazoles via direct oxidative N‐α‐C(sp3)‐H functionalization of arylmethylamines. The readily available arylmethylamines as a substrate have afforded tetrasubstituted imidazoles products up to 94% yields under mild and environmentally benign conditions. The explored substrates scope with 1,2‐diketones and α‐hydroxyketones have shown great utility for synthesis of tetrasubstituted imidazoles. [ABSTRACT FROM AUTHOR]

Here, we report a new series of Co(II), Ni(II), Cu(II) and Zn(II) metal complexes (1–20) derived from hydrazone ligands [Nʹ-((E)-3-(4-nitrophenyl)allylidene)benzohydrazide] HL1, [Nʹ-((E)-3-(4-nitrophenyl)allylidene)nicotinohydrazide] HL2, [Nʹ-((E)-3-(4-nitrophenyl)allylidene)isonicotinohydrazide] HL3, [4-methyl-Nʹ-((E)-3-(4-nitrophenyl)allylidene)benzohydrazide] HL4 which were obtained from condensation reaction of 4-nitrocinnemaldehyde with benzo/ nicotinic/ iso-nicotinic/ p-toluic hydrazide. The structure elucidation was deduced from spectral and physicochemical techniques like 1H NMR, 13C NMR, FT-IR, UV–Vis, ESR, SEM, TGA/DTG, XRD, HRMS, molar conductance measurements and elemental analysis. Also, DFT (B3LYP/LanL2DZ) computations have been conducted for ligand and its metal complexes to study the structural and energetics behaviour. The spectral and physicochemical techniques suggested octahedral geometry of all the afforded metal complexes with hydrazone ligands in (1 M: 2L) molar ratio having molecular formula of the type [M(L1−4)2(H2O)2]. Thermal analysis suggested that the complexes were stable up to 190 °C and that water molecules are coordinated to metal ions in complexes. XRD data revealed crystalline nature of compounds and scanning electron microscopy (SEM) suggested that metal complexes have different surface morphology as compared to hydrazone ligands. In vitro antioxidant potential of synthesized compounds was assessed and investigation revealed that metal complexes have more efficiency of decolourizing the DPPH solution as compared to ligands. To ascertain the therapeutic aspects of synthesized compounds, in vitro antimicrobial assessment was performed on four bacterial strains (Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli) and two fungal strains (Candida albicans, Aspergillus niger) taking ciprofloxacin and fluconazole as reference drugs, respectively. Compounds 11, 12, 15, 16, 19 and 20 were found to be potent antimicrobial agent among the tested series. Thus, this investigation gave a vision into the structural-based modification of hydrazones and their complexation with metals could enhance biological activities.4 [ABSTRACT FROM AUTHOR]

Background: Diagnosing immune checkpoint inhibitor (ICI)-associated nephritis can be challenging since it is a rare complication of therapy, associated with a spectrum of immune-mediated pathologies, and can present months after ICI therapy discontinuation (i.e., late-onset). ICIs are increasingly administered in combination with other cancer therapies with associated nephrotoxicity, further obfuscating the diagnosis of ICI-associated nephritis. In this report, we describe the first suspected case of late-onset ICIassociated membranous nephropathy (MN) in a patient with metastatic clear cell renal cell carcinoma (RCC) who had discontinued ICI therapy 6 months prior to presentation. Prompt recognition of the suspected late-onset immune-related adverse event (irAE) resulted in the successful treatment of MN and continuation of RCC therapy. Case presentation: A 57-year-old man with metastatic clear cell RCC was responsive to third-line RCC therapy with lenvatinib (oral TKI) and everolimus (oral mTOR inhibitor) when he presented with nephrotic range proteinuria and acute kidney injury (AKI). His kidney biopsy revealed probable secondary MN with subendothelial and mesangial immune complex deposits and negative staining for both phospholipase A2 receptor (PLA2R) and thrombospondin type-1 domain-containing 7A (THSD7A). While a diagnosis of paraneoplastic MN could not be excluded, the patient was responding to cancer therapy and had tumor regression. However, 6 months prior to presentation, the patient had received pembrolizumab, an ICI, with his first-line RCC treatment. Due to concern that the patient may be presenting with late-onset ICI-associated MN, he was effectively treated with rituximab, which allowed for his continued RCC therapy. Conclusion: This report highlights the first case of suspected late-onset ICIassociated MN and the increasing complexity of recognizing renal irAEs. With the growing indications for the use of ICIs in combination with other cancer therapies, recognizing the various presentations of ICI-immune nephritis can help guide patient management and treatment. [ABSTRACT FROM AUTHOR]

A series of new pyrimidine-based nitrogen-rich green energetic materials were effectively synthesized from commercially available inexpensive starting materials, with short reaction times, easy isolation, and essentially quantitative yields. All the molecules were fully characterized using IR, multinuclear nuclear magnetic resonance (NMR), and mass spectra. Compounds 2, 4 and 5 were characterized by 15N NMR spectroscopy, and compound 4 was confirmed by single-crystal X-ray diffraction studies. The physicochemical properties of the pyrimidine derivatives were investigated theoretically and experimentally in detail. Compounds 2, 3, 9, 10 and 12 exhibit excellent detonation properties, good thermostability and low sensitivity comparable with secondary benchmark explosives RDX and HMX. It is noteworthy that for compounds 3, 9 and 10, the values of the heats of formation, detonation velocities and pressures, decomposition temperatures, and impact sensitivities were determined to be >250 kJ mol−1, >9380 m s−1, >32 GPa, >170 °C, and >30 J, respectively. In addition, the activation energy and nonisothermal thermokinetic parameters for compounds 2, 9 and 10 were determined by using the Kissinger method. It was found that incorporating hydrazine, nitro, and N-oxide groups into the pyrimidine backbone leads to strong non-bonded interactions, which helps to enhance the thermal stability and lower the sensitivity. These results are expected to assist in improving the synthesis strategy of balancing the detonation performance and safety parameters of a new generation of green energetic materials. [ABSTRACT FROM AUTHOR]

An attractive synthetic route was devaluped for making N‐(4‐(1,2,4‐oxadiazol‐3‐yl)‐1,2,5‐oxadiazol‐3‐yl) formamide (4) and di(1,2,4‐oxadiazol‐3‐yl) methanone O‐(nitrodi(1,2,4‐oxadiazol‐3‐yl)methyl) oxime (6) from commercially available inexpensive malononitrile starting material with easy purification, short experimental time and high yields at room temperature. The chemical structures of 4 and 6 were identified by NMR, IR, EA and verified by single‐crystal X‐ray studies. A plausible mechanism is proposed for the conversion of 4 to 6. Furthermore, both compounds have been evaluated for energetic applications. Based on their insensitive nature and good detonation performance, they are potential energetic materials. [ABSTRACT FROM AUTHOR]

A new series of 1-Thiazolyl-2-Pyrazolines 5a-g was accomplished by reacting pyrazolealdehyde with an appropriate aromatic ketone in the presence of PEG-300 as a solvent to yield chalcone. The chalcones reacted with thiosemicarbazide to yield asymmetric 1-thiocarbamoyl pyrazoles. The above formed 1-thiocarbamoyl pyrazoles reacted with appropriate α- haloketones to yield 1-Thiazolyl-2-Pyrazolines. The structural interpretations of newly formed compounds were done by 1H NMR, 13CNMR, IR and mass spectroscopic methods. The newly prepared asymmetric 1-Thiazolyl-2-pyrazoline derivatives were evaluated to their in vitro antioxidant (H2O2, DPPH, SOR and NO radical inhibiting activity) as well as anti-inflammatory activity. The 1-Thiazolyl-2-pyrazoline derivatives 5a-g exhibited moderate to good H2O2 scavenging activity as match up to ascorbic acid. All the 1-Thiazolyl-2-pyrazoline derivatives exhibited excellent SOR scavenging activity except 5 b. All the tested compounds have shown good to excellent, NO radical inhibiting activity. DPPH radical scavenging activity results have shown low antioxidant activity. Also, all the 1-Thiazolyl-2-pyrazoline derivatives were tested for their in vitro anti-inflammatory activity. The compounds 5a, 5 b, 5c, 5f and 5 g were exhibited good anti-inflammatory activity and 5d showed moderate activity while 5e less active as match up to diclofenac sodium as a standard reference. [ABSTRACT FROM AUTHOR]

Ammonium DiNitramide (ADN) is one of the most promising green energetic oxidizers for future rocket propellant formulations. In the present work, we report a detailed theoretical study on structural, elastic, and vibrational properties of the emerging oxidizer under hydrostatic compression using various dispersion correction methods to capture weak intermolecular (van der Waals and hydrogen bonding) interactions. The calculated ground state lattice parameters, axial compressibilities, and equation of state are in good accord with the available experimental results. Strength of intermolecular interactions has been correlated using the calculated compressibility curves and elastic moduli. Apart from this, we also observe discontinuities in the structural parameters and elastic constants as a function of pressure. Pictorial representation and quantification of intermolecular interactions are described by the 3D Hirshfeld surfaces and 2D finger print maps. In addition, the computed infra-red (IR) spectra at ambient pressure reveal that ADN is found to have more hygroscopic nature over Ammonium Perchlorate (AP) due to the presence of strong hydrogen bonding. Pressure dependent IR spectra show blue- and red-shift of bending and stretching frequencies which leads to weakening and strengthening of the hydrogen bonding below and above 5 GPa, respectively. The abrupt changes in the calculated structural, mechanical, and IR spectra suggest that ADN might undergo a first order structural transformation to a high pressure phase around 5-6 GPa. From the predicted detonation properties, ADN is found to have high and low performance characteristics (DCJ = 8.09 km/s and PCJ = 25.54 GPa) when compared with ammonium based energetic oxidizers (DCJ = 6.50 km/s and PCJ = 17.64 GPa for AP, DCJ = 7.28 km/s and PCJ = 18.71 GPa for ammonium nitrate) and well-known secondary explosives for which DCJ = ~8-10 km/s and PCJ = ~30-50 GPa, respectively. [ABSTRACT FROM AUTHOR]

A simple process of arylmethylamines C(sp3)−H bond functionalization under aerobic condition has been developed for 3,3'‐bis(indolyl)methanes (BIMs) and tris(indolyl)methanes synthesis in presence of various substituted indoles. The present transformation accounts BIMs in excellent yields up to 94 %viaC−C and C−N bond formation in short reaction time represents fine alternative route. The catalytic performance of iodine shows good tolerance towards different functional groups, and has great utility in exploring substrate scope. [ABSTRACT FROM AUTHOR]

The present investigation is an extensive study of surface and ground water quality of Madathukulam taluk, Tiruppur District, Tamil Nadu, India, to estimate the quality of water using Modified Water Quality Index (MWQI) and Geographic Information System (GIS) technique. In this study 35 water samples from Open well, Bore well, River, Lake and Pond were analysed for the physicochemical parameters like pH, temperature, total phosphate, total nitrate, turbidity, total dissolved solids, dissolved oxygen, biological oxygen demand, faecal coliform, electrical conductivity, total hardness, chloride, fluoride, sodium and potassium. The resulting values were computed to investigate the quality of water using geographic information system and water quality index and compared with the standard drinking water guidelines proposed by the WHO (2017) and BIS (2012) for drinking and agricultural purpose. Inverse distance weighted (IDW) interpolation technique was used for preparing the spatial distribution maps for each physiochemical parameter. The analytical result signifies that 40% of the study areas are slightly acidic. GIS based water quality index shows that 63% of the area has recorded with good quality water, while the remaining 37% are of medium quality of water. The MWQI proved to be a useful method to classify the water similar to NSF-WQI in Madathukulam Taluk. [ABSTRACT FROM AUTHOR]

In this work, the assessment of surface and ground water quality of Palladam Taluk, Tiruppur, district, Tamil Nadu, India were carried out using Geographical Information System (GIS) and Modified National Sanitation Foundation -Water Quality Index (MNSFWQI). Four samples from surface and twenty seven samples from ground water sources were taken from Palladam Taluk, Tiruppur District. In the current study, the surface and ground water samples were analysed for temperature, pH, dissolved oxygen (DO), electrical conductivity (EC), biological oxygen demand (BOD), turbidity, total dissolved solids (TDS), total hardness (TH), faecal coliforms (FC), total phosphate (TP), total nitrate (TN), chlorides (Cl-), sodium (Na+) and fluoride (F-) ions to investigate the suitability of surface and ground water for drinking and agricultural purposes through Geographic information system (GIS) and modified national sanitation foundation water quality index (MNSF-WQI) technique. The concentrations of TH, TDS, Cl- and Na+ were observed to be above the desirable limit of World Health Organization (WHO) guidelines and Bureau of Indian Standards (BIS). whereas F-, BOD, DO, EC, TP, TN, FC and temperature were within the acceptable limits. The GIS-based WQI map analysis indicated that 45% of the study area having good water quality index and the remaining area showed medium quality water. Dyeing and textile industries in the study area are responsible for deteriorating the quality to medium quality of water which was not appropriate for direct utilization and needed prior treatment. There is no detailed report on assessment of the surface and ground water quality of Palladam Taluk in Tamil Nadu using GIS and MNSF-WQI techniques. [ABSTRACT FROM AUTHOR]

This paper describes the preparation, broad characterization and study of activity in hydrogenation and hydroformylation reactions of an easily produced 0.18% Rh/Al2O3. Analytical studies on fresh and recycled samples shed light on the smart properties of such catalyst. Results showed high activity as well as fine/excellent chemoselectivity or regioselectivity, characteristics that may suggest a wide range of applicability. The low metal content catalyst 0.18% Rh/Al2O3 was very active in both hydrogenation and hydroformylation reactions so providing intermediates for valuable APIs, as Nabumetone and Eletriptan, and a fragrance with a fresh, green-floral smell, that recalls scent of lily of the valley. [ABSTRACT FROM AUTHOR]

The oxadiazole ring is an essential nitrogen-containing heterocycle and a valuable building block that is used in developing numerous functionalized energetic compounds. To understand the effect of multiple oxadiazole rings on energetic performance and sensitivities, we investigated oxadiazole rings connected with C–C and N＝N bond-possessing –NO2 and –NHNO2 groups. The results show that skeletal energy can be increased by the incorporation of oxadiazoles. All the studied compounds have positive heat of formation (> 410 kJ mol−1) that are larger than those of 3,4-dinitrofurazan (O1, 219 kJ mol−1) and N,N′-1,2,5-oxadiazole-3,4-diyldinitramide (O7, 254 kJ mol−1). Even though various molecular combinations offer unlimited structural diversity options and energetic properties, the linear addition of oxadiazole rings efficiently reduces sensitivity but with decreased oxygen balance and detonation performance. To achieve a balance between sensitivity and detonation performance, incorporating oxadiazole rings in the molecular framework may be considered as an efficient scaffold and can significantly assist in the progress of developing new energetic compounds. [ABSTRACT FROM AUTHOR]

Nitrogen‐rich polyazole derivatives were designed and synthesized from the commercially available 4,5‐dicyano‐2‐aminoimidazole. The relatively simple synthesis of multiple azole rings in desired compounds with good yields allows for an efficient scale‐up. All synthesized compounds were characterized by NMR and vibrational spectroscopy, elemental analysis, and DSC studies. The impact and friction sensitivities were measured by the BAM apparatus. The energy content of the target compounds was predicted by using density functional methods. Performing cautious characterization point out that these compounds offer a good combination of high nitrogen‐ and energy‐content with insensitivity towards friction and impact stimuli. These results indicate the superior potential of these nitrogen‐rich polyazole derivatives for enthalpy enhancement, gas generant, and cationic components in energetic salts. [ABSTRACT FROM AUTHOR]

A series of three different classes of benzothiazole linked 1,2,3‐triazole hybrid molecules with varying alkyl spacers (ethyl, propyl, and butyl) between 2‐hydroxyphenyl benzothiazoles and 1,2,3‐triazoles are efficiently synthesized under CuAAC condition. All compounds are satisfactorily characterized by FTIR, 1H‐NMR, 13C‐NMR, ESI‐MS data and structures of some compounds were finally supported by single‐crystal X‐ray diffraction data. Most of the synthesized compounds exhibited good to better DNA binding property (0.28×105 M−1 to 2.91×105 M−1) and well drug‐like properties. Some promising compounds showed good agreement to all experimental and theoretical computed properties (fluorescence study, DNA binding, molecular docking, DFT, and ADME Predictions). [ABSTRACT FROM AUTHOR]

This article describes the syntheses, characterization, and energetic properties of 4, 6-diazido-N, N-dimethyl-1, 3, 5-triazin-2-amine and 2, 4, 6-tris (5-(3, 5-dinitrophenyl)-1H-tetrazol-1-yl)-1, 3, 5-triazine. Also, this paper emphasizes the insensitive and thermally stable energetic molecules like melem, melem-ammonium perchlorate mixture, and hydrazinium cyamelurate. All these compounds possess good energetic properties viz., the heat of formation and heat of combustion. Synthesis and characterizations and energetic properties of 4, 6-diazido-N, N-dimethyl-1, 3, 5-triazin-2-amine (3); 2, 4, 6-tris (5-(3, 5-dinitrophenyl)-1H-tetrazol-1-yl)-1, 3, 5-triazine (4) and hydrazinium cyamelurate (10) are described. The thermal stabilities, energetic properties and sensitivity parameters are compared with standard high-energy materials. (i) Syntheses and characterization of 4, 6-diazido-N, N-dimethyl-1, 3, 5-triazin-2-amine (3); 2, 4, 6-tris (5-(3, 5-dinitrophenyl)-1H-tetrazol-1-yl)-1, 3, 5-triazine (4) and hydrazinium cyamelurate (10) are described. (ii) Experimental energetic properties and sensitivity parameters of these compounds were discussed. [ABSTRACT FROM AUTHOR]

Eight new energetic salts combining N-bases (amines) with picrate ions were synthesized in high yields and characterized by NMR (1H and 13C), IR spectroscopy, elemental analysis, and differential thermal analysis. Single-crystal structural studies were performed to confirm the structures, packing, and various interactions in the salts. Interestingly, salts 1 and 7 exist in different polymorphic forms and the effect of solvent on polymorphism was examined (i.e. solvatomorphism). Thermal stability and impact and friction sensitivities were also determined to understand the relationship between their structures and properties. Salt 3 with hydrazinium cations showed higher performance (d = 1.82 g cm−3; Td = 255.2 °C; D = 7.95 km s−1; P = 28.2 GPa; IS ≥ 30 J; FS ≥ 350 N) towards energetic applications. However, salts 4, 7, and 8 also exhibit good performance parameters, which are marginally better as compared to TNT. The tuning of the physiochemical properties and performances was carried out with the modification of the cationic-amine molecules and the molar ratio of the reactants. [ABSTRACT FROM AUTHOR]

In this study, high energy materials (HEMs) derived from 1,2,4‐triazolo[3,4‐d]‐1,2,4‐triazolo[3,4‐f]furazano[3,4‐b]pyrazine (TTFP) substituted with −NH2, −NHNO2, −ONO2, −NO2, and −N3 explosophoric groups were designed and computationally characterized. Density functional calculations with B3PW91/6‐31G(d,p) method were used to explore the optimized structures, energetic properties, and sensitivity of TTFP derivatives. It is found that the TTFP is an effective molecular backbone for improving the energy content and energetic performance of the designed compounds. The effect of various explosophoric groups on energy content, density, detonation performance, and sensitivity was investigated. The energetic evaluation indicated that TTFP derivatives having −NHNO2 (F4), −ONO2 (F5), and −NO2 (F6) groups demonstrate good detonation performances and exceed the performance of TNT and close to that of RDX. Compounds F4‐F6 displays the best energetic properties (density > 1.85 g/cm3, detonation velocity >8.30 km/s, detonation pressure > 32.0 GPa). Considering the energetic properties, the TTFP backbone can be regarded as an energy‐rich unit, which can be substituted with suitable explosophoric groups for constructing HEMs. [ABSTRACT FROM AUTHOR]

A series of energetic compounds were derived from [1,2,4]triazolo[1,5-a][1,3,5]triazine and azo-bridged fused backbone by introducing the –NO2, –NHNO2, –ONO2, –N3, and –NH2 explosophoric groups. The influence of explosophoric groups on energetic properties has been explored. All the compounds exhibit positive energy content (34.4–1955.4 kJ/mol) and densities (1.71–1.99 g/cm3) subject to fused triazole and triazine framework and various functional groups. The designed compounds with –NHNO2, –ONO2, and –NO2 functional groups possess high detonation velocities (8.23–9.00 km/s), pressures (30.94–37.68 GPa), Gurney velocities (2.70–2.88 km/s), and power index (109–131%) superior to TNT (6.94 m/s, 22.0 GPa, 2.37 km/s, and 118%) and comparable with RDX (8.60 km/s, 33.92 GPa, 2.93 km/s, and 169%) and HMX (8.90 km/s, 38.39 GPa, 2.97 km/s, and 169%). Based on high nitrogen and energy content, performance parameters, and sensitivity data, the designed compounds show high potential to be used as energetic materials. [ABSTRACT FROM AUTHOR]

There is broad interest in engineering phenylalanine ammonia-lyase (PAL) for its biocatalytic applications in industry and medicine. While site-specific mutagenesis has been employed to improve PAL stability or substrate specificity, combinatorial techniques are poorly explored. Here, we report development of a directed evolution technique to engineer PAL enzymes. Central to this approach is a high-throughput enrichment that couples E. coli growth to PAL activity. Starting with the PAL used in the formulation of pegvaliase for PKU therapy, we report previously unidentified mutations that increase turnover frequency almost twofold after only a single round of engineering. [ABSTRACT FROM AUTHOR]

The production of reactive oxygen species (ROS) during cryopreservation of semen alters the sperm motion and mobility characteristics, resulting in poor or failure of conception rate after artificial insemination (AI). Melatonin an antioxidant is able to modulate the effect of ROS and prevents spermatozoa by reducing the oxidative stress during freezing process. Eight ejaculates from eight healthy HF bulls diluted with Tris egg yolk glycerol extender were divided into five equal aliquots. The Computer Assisted Semen Analyser (CASA) results showed no significant difference between the control—post‐ thaw samples and melatonin‐treated samples; however, the velocity of spermatozoa with regard to the VAP, VSL showed highest increase in the 0.25 mM MLT‐treated semen followed by 0.1 mM MLT treated semen except for VCL where velocity increased with increase in the concentration of melatonin. The vigour of spermatozoa regard to BCF, STR and LIN recorded highest increase in the 0.25 mM MLT treated semen followed by 0.1 mM MLT‐treated semen except for the ALH where vigour increased with increase in the concentration of melatonin. The electron micrography images illustrated that the addition of 0.1 mM melatonin protected the plasma membrane and acrosome region and maintained the ultrastructure integrity of the cryopreserved spermatozoa when compared to control group, whereas the electron micrography of spermatozoa treated with 0.2 and 0.25 mM melatonin illustrated highest damage to the plasma and acrosome membrane. Thus concluding that inclusion of melatonin to sperm extender can improve the post‐thaw quality of cryopreserved bull spermatozoa. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) has been applied to understand the influence of various linkages on the energetic properties and stability of the polynitro-biphenyl compounds. Structures were optimized using the B3PW91/6-31G(d,p) level, and the heats of formation (HOFs) were computed by employing the selected isodesmic reactions. The results reveal that the –N=N– linkage helps to gain high HOF while the –O–, –NH–C(O)NH–, and –NH–C(O)–C(O)–NH– show a negative impact on energy content. Kamlet-Jacobs (K-J) equations were used to determine detonation properties based on the computed densities and HOFs, while stability and sensitivity were investigated by correlating with the bond dissociation energy (BDE), charge on the nitro group, and the balance parameter on surface potentials. Comparing the effect of different linkages on performance and stability of selected polynitro-biphenyl derivatives reveals that –NH–NH– and –N=N– are suitable for a connection between energetic moieties and these results are expected to demonstrate primary information for designing new energetic materials. [ABSTRACT FROM AUTHOR]

Bilothorax is a rare cause of an exudative pleural effusion. The diagnosis is confirmed by a pleural fluid to serum bilirubin ratio of greater than 1. Typically, bilothorax presents as a right-sided effusion due to its proximity to the liver and biliary system. Herein, we present a case of isolated left-sided bilothorax in a 43-year-old female admitted with sickle cell crisis. Only one other case of isolated spontaneous left-sided bilothorax has been described in the literature. A thoracentesis performed on admission demonstrated greenish fluid and bilothorax was suspected, with a pleural fluid to serum bilirubin ratio greater than 1 confirming the diagnosis. A magnetic resonance cholangiopancreatography (MRCP) showed an abnormal 90-degree acute angulation in the mid-to-distal common bile duct with proximal common bile duct and intrahepatic bile ducts dilation. This was further confirmed with an endoscopic retrograde cholangiopancreatography (ERCP), which did not reveal any extravasation of contrast into the left pleural space. Ultimately, despite the use of various modalities, no definitive cause of bilothorax was identified. Postthoracentesis imaging revealed evidence of fibrothorax, a direct and permanent complication of bilothorax. The presence of an isolated left-sided bilothorax, along with the lack of a confirmed etiology, makes this case unique. [ABSTRACT FROM AUTHOR]

Saxagliptine hydrochloride, PEG, polaxamer-407,ethyl cellulose were prepared to study the dissolution of sparingly water soluble Saxagliptine hydrochloride drug. solid dispersion of Saxagliptine hydrochloride were prepared using different ratios of PEG 6000 & Polaxamer-407.Some of the practical aspects to be considered for the preparation of solid dispersion such as selection of polymers, methods of preparation solubility of drug and dissolution study of drug in solid dispersion are also discussed. The present research provides a there is increase in solubility of Saxagliptine hydrochloride and also solid dispersion complex of drug was giving better dissolution profile as compared to other solid dispersions this imporove bioavailability. FT-IR, shows the compatability of drug & carrier. [ABSTRACT FROM AUTHOR]