Synthesis of hydrazinyl-thiazole ester derivatives, in vitro trypanocidal and leishmanicidal activities

Aim: To synthesize novel more potent trypanocidal and leishmanicidal agents. Methods: Hantzsch's synthetic strategy was used to synthesize 1,3-thiazole-4-carboxylates and their N-benzylated derivatives. Results: 28 new thiazole-carboxylates and their N-benzylated derivatives were established to test their trypanocidal and leishmanicidal activities. From both series, compounds 3b, 4f, 4g, 4j and 4n exhibited a better or comparable trypanocidal profile to benznidazole. Among all tested compounds, 4n was found to be the most potent and was better than benznidazole. Conclusion: Further variation of substituents around 1,3-thiazole-4-carboxylates and or hydrazinyl moiety may assist in establishing better and more potent trypanocidal and leishmanicidal agents.

Facile Synthesis and DFT Analysis of Novel Thiazole-Based Hydrazones: An Experimental and Theoretical Perspective

Hydrazone compounds with remarkable nonlinear optical (NLO) properties were found with vast applications due to their cost-effective synthesis and greater stability. Therefore, we synthesized hydrazone scaffolds (TCAH1-TCAH8) by condensation reaction, and their structural confirmation was accomplished with spectroscopic methods (1H-, 13C-NMR, and HRMS). Quantum chemical calculations were also performed at B3PW91/6-311G(d,p) functional of DFT to explore electronic, structural, and chemical properties. To understand the NLO responses of afore-said chromophores, various kinds of analyses such as natural bonding orbitals (NBOs), frontier molecular orbitals (FMOs), UV-vis analysis, and density of states (DOS) were performed. Findings showed that the HOMO-LUMO energy gap in TCAH8 (3.595 eV) was found to be lower than the TCAH1-TCAH7 (4.123-3.932 eV) with a large red shift which leads to a substantial NLO response. Furthermore, strong intramolecular interactions showed the highest stabilization energy (24.1 kcal mol-1) for TCAH8 in the NBO transitions, combined with the least binding energy. The significant NLO response of TCAH4 was explored with ⟨α⟩, βtot, and ⟨γ⟩ values as 5.157 × 10-23, and 2.185 × 10-29, and 2.753 × 10-34 esu, respectively, among the entitled compounds. The recent findings may inspire scientists to develop extremely effective NLO materials for forthcoming hi-tech applications.

Synthesis of hydrazinylthiazole carboxylates: a mechanistic approach for treatment of diabetes and its complications

Aim: The deaths of thousands of people and millions affected by diabetes mellitus triggered us to look for alternative possible solutions to cure diabetes and its complications. Materials & methods: A series of hydrazinylthiazole carboxylates (3a-n) was prepared by cyclocondensation reaction of thiosemicarbazones with ethyl 2-chloroacetoacetate. These compounds were screened for antidiabetic potential through α-amylase inhibition, antiglycation and antioxidant assays. Results & conclusion: Most of the compounds exhibited a promising antidiabetic property. Compounds 3e and 3h showed excellent α-amylase and glycation inhibition properties. The hemolytic assay indicated that all compounds are biocompatible. Docking studies carried out on α-amylase target showed correlation between in vitro inhibition and binding energy.

4-Adamantyl-(2-(arylidene)hydrazinyl)thiazoles as potential antidiabetic agents: experimental and docking studies

Aim: To develop an efficient and cost-effective antidiabetic agent. Methods: A simple and convenient Hantzsch synthetic strategy was used to prepare 4-adamantyl-(2-(arylidene)hydrazinyl)thiazoles. Results: Fifteen newly established structures of 4-adamantyl-(2-(arylidene)hydrazinyl)thiazoles were tested for their α-amylase, antiglycation and antioxidant activities. Almost all tested compounds showed excellent α-amylase inhibition. Compounds 3a and 3j exhibited the highest potency, with IC₅₀ values of 16.34 ± 2.67 and 16.64 ± 1.12 μM, respectively. Compounds 3c and 3i exhibited comparable antiglycation potential with the standard, aminoguanidine. The antioxidant potential of compound 3g was found to be excellent, with an IC₅₀ value of 28.19 ± 0.2563 μM. The binding interactions of compound 3a (binding energy = -8.833 kcal/mol) with human pancreatic α-amylase identified 3a as a potent α-amylase inhibitor. Conclusion: Enrichment of established structures with more electron-donating functionalities may assist/lead to the development of more potent antidiabetic drugs.

Synthesis of Thiazole-Chalcone Hybrid Molecules: Antioxidant, Alpha(α)-Amylase Inhibition and Docking Studies

The molecular hybrid approach is very significant to combat various drug-resistant disorders. A simple, convenient, and cost-effective synthesis of thiazole-based chalcones is accomplished, using a molecular hybrid approach, in two steps. The compound 1-(2-phenylthiazol-4-yl)ethanone (3) was used as the main intermediate for the synthesis of 3-(arylidene)-1-(2-phenylthiazol-4-yl)prop-2-en-1-ones (4a-f). Thin layer chromatography was used to testify the formation and purity of all synthesized compounds. Further structural confirmation of all compounds was achieved via different spectroscopic techniques (UV, FT-IR, ¹ H- and ¹³ C-NMR) and elemental analysis. All synthesized compounds were tested for their α-amylase inhibition and antioxidant potential. The cytotoxic property of compounds was also tested with in vitro haemolytic assay. All tested compounds showed moderate to excellent α-amylase inhibition and antioxidant activity. All tested compounds are found safe to use due to their less toxicity when compared to the standard Triton X. The molecular docking simulation study of all synthesized compounds was also conducted to examine the best binding interactions with human pancreatic α-amylase (pdb: 4 W93) using AutodockVina. The molecular docking results authenticated the in vitro amylase inhibition results, i.e., 3-(3-Methoxyphenyl)-1-(2-phenylthiazol-4-yl)prop-2-en-1-one (4e) exhibited lowest IC₅₀ value 54.09±0.11  μM with a binding energy of -7.898 kcal/mol.

Synthesis of Fluorinated Hydrazinylthiazole Derivatives: A Virtual and Experimental Approach to Diabetes Management

A novel series of fluorophenyl-based thiazoles was synthesized following the Hanztsch method. All of the compounds were initially verified with physical parameters (color, melting point, retardation factor (R _f)), which were further confirmed by several spectroscopic methods, including ultraviolet-visible (UV-visible), Fourier-transform infrared (FTIR), ¹H, ¹³C, ¹⁹F NMR, and high-resolution mass spectrometry (HRMS). The binding interactions of all compounds were studied using a molecular docking simulation approach. Furthermore, each compound was evaluated for its alpha(α)-amylase, antiglycation, and antioxidant potentials. The biocompatibility of all compounds was checked with an in vitro hemolytic assay. All synthesized scaffolds were found biocompatible with minimal lysis of human erythrocytes as compared to the standard Triton X-100. Among the tested compounds, the analogue 3h (IC₅₀ = 5.14 ± 0.03 μM) was found to be a highly potent candidate against α-amylase as compared to the standard (acarbose, IC₅₀ = 5.55 ± 0.06 μM). The compounds 3d, 3f, 3i, and 3k exhibited excellent antiglycation inhibition potential with their IC₅₀ values far less than the standard amino guanidine (IC₅₀ = 0.403 ± 0.001 mg/mL). The antidiabetic potential was further supported by docking studies. Docking studies revealed that all synthesized compounds exhibited various interactions along enzyme active sites (pi-pi, H-bonding, van der Waals) with varied binding energies.

Synthesis, characterization and exploration of photovoltaic behavior of hydrazide based scaffolds: a concise experimental and DFT study

Solar energy being a non-depleting energy resource, has attracted scientists' attention to develop efficient solar cells to meet energy demands. Herein, a series of hydrazinylthiazole-4-carbohydrazide organic photovoltaic compounds (BDTC1-BDTC7) with an A1-D1-A2-D2 framework was synthesized with 48-62% yields, and their spectroscopic characterization was accomplished using FT-IR, HRMS, ¹H and ¹³C-NMR techniques. Density functional theory (DFT) and time dependent DFT analyses were performed utilizing the M06/6-31G(d,p) functional to calculate the photovoltaic and optoelectronic properties of BDTC1-BDTC7via numerous simulations of the frontier molecular orbitals (FMOs), transition density matrix (TDM), open circuit voltage (V _oc) and density of states (DOS). Moreover, the conducted analysis on the FMOs revealed efficient transference of charge from the highest occupied to the lowest unoccupied molecular orbitals (HOMO → LUMO), further supported by TDM and DOS analyses. Furthermore, the values of binding energy (E _b = 0.295 to 1.150 eV), as well as reorganization energy of the holes (-0.038-0.025 eV) and electrons (-0.023-0.00 eV), were found to be smaller for all the studied compounds, which suggests a higher exciton dissociation rate with greater hole mobility in BDTC1-BDTC7. V _oc analysis was accomplished with respect to HOMO_PBDB-T-LUMO_ACCEPTOR. Among all the synthesized molecules, BDTC7 was found to have a reduced band gap (3.583 eV), with a bathochromic shift and absorption maximum at 448.990 nm, and a promising V _oc (1.97 V), thus it is regarded as a potential candidate for high performance photovoltaic applications.

Design, and synthesis of selectively anticancer 4-cyanophenyl substituted thiazol-2-ylhydrazones

Cyclization of substituted thiosemicarbazones with α-bromo-4-cyanoacetophenone allows rapid single-step sustainable syntheses of 4-cyanophenyl-2-hydrazinylthiazoles libraries (30 examples, 66-79%). All show anticancer efficacy against HCT-116 and MCF-7 carcinoma cell lines with the majority being more active than cisplatin positive controls. The compounds 2-(2-(2-hydroxy-3-methylbenzylidene)hydrazinyl)-4-(4-cyanophenyl)thiazole (3f) and 2-(2-((pentafluorophenyl)methylene)-hydrazinyl)-4-(4-cyanophenyl)thiazole (3a') show optimal GI50 values (1.0 ± 0.1 μM and 1.7 ± 0.3 μM) against MCF-7 breast cancer cells. Against colorectal carcinoma HCT-116 cells, (2-(2-(3-bromothiophen-2-yl)methylene)hydrazinyl)-4-(4-cyanophenyl)thiazole (3b'), 2-(2-(2-hydroxy-3-methylbenzylidene)hydrazinyl)-4-(4-cyanophenyl)thiazole (3f), 2-(2-(2,6-dichlorobenzylidene)hydrazinyl)-4-(4-cyanophenyl)thiazole (3n) and 2-(2-(1-(4-fluorophenyl)ethylidene)hydrazinyl)-4-(4-cyanophenyl)thiazole (3w) are the most active (GI50 values: 1.6 ± 0.2, 1.6 ± 0.1, 1.1 ± 0.5 and 1.5 ± 0.8 μM respectively). Control studies with MRC-5 cells indicate appreciable selectivity towards the cancer cells targeted. Significant (p < 0.005) growth inhibition and cytotoxicity effects for the thiazoles 3 were corroborated by cell count and clonogenic assays using the same cancer cell lines at 5 and 10 μM agent concentrations. Cell cycle, caspase activation and Western blot assays demonstrated that compounds 3b' and 3f induce cancer cell death via caspase-dependent apoptosis. The combination of straight forward synthesis and high activity makes the thiazoles 3 an interesting lead for further development.

Synthesis of Arylidenehydrazinyl-4-methoxyphenylthiazole Derivatives: Docking Studies, Probing Type II Diabetes Complication Management Agents

Thiazole has been a key scaffold in antidiabetic drugs. In quest of new and more effective drugs a simple, efficient, high yielding (67-79%) and convenient synthesis of arylidenehydrazinyl-4-methoxyphenyl)thiazoles is accomplished over two steps. The synthesis involved the condensation of aryl substituted thiosemicarbazones and 2-bromo-4-methoxyacetophenone in absolute ethanol. The structures of the resulting thiazoles are in accord with their UV-Vis, FT-IR, 1 H-, 13 C-NMR and HRMS data. All compounds were evaluated for alpha(α)-amylase inhibition potential, antiglycation, antioxidant abilities and biocompatibility. The compounds library identified 2-(2-(3,4-dichlorobenzylidene)hydrazinyl)-4-(4-methoxyphenyl)thiazole as a lead molecule against α-amylase inhibition with an IC 50 of 5.75±0.02 µM. α-Amylase inhibition is also supported by molecular docking studies against amylase. All the obtained thiazoles also showed promising antiglycation activity with 4-(4-methoxyphenyl)-2-(2-(2-(trifluoromethyl)benzylidene)hydrazinyl)thiazole exhibiting the best inhibition (IC 50 = 0.383±0.001 mg/mL) compared to control. The tested compounds are also biocompatible at the concentration used i.e. 10 µM.

Synthesis, Characterization, and DFT-Based Electronic and Nonlinear Optical Properties of Methyl 1-(arylsulfonyl)-2-aryl-1H-benzo[d]imidazole-6-carboxylates

Herein, a series of N-1-sulfonyl substituted derivatives of 2-substituted benzimidazoles (2a-2e) were designed and synthesized via structural tailoring of the acceptor part of donor-π-acceptor schemes, and their nonlinear optic (NLO) characteristics were reported. The structures of 2a-2e were investigated and their characterization was accomplished by employing spectroscopic procedures, i.e., UV-vis, FT-IR, and ¹H and ¹³C NMR. Further, a density functional theory (DFT) approach was used to calculate UV-vis, vibrational, and ¹H and ¹³C NMR techniques; frontier molecular orbitals (FMOs); global reactivity parameters (GRPs); natural bond orbitals (NBOs); optical and vibrational analysis; and nonlinear optics (NLO). The most promising results were obtained for 6-nitro-2-(4-nitrophenyl)-1-(4-nitrophenylsulfonyl)-1H-benzo[d]imidazole among entitled compounds, as it exhibited the highest ⟨α⟩ and β_tot values, showing it is an eye-catching NLO material. This DFT study evokes the interest of researchers regarding the development of benzimidazole-based tempting NLO compounds that could be beneficial in modern hi-tech applications.

Synthesis, crystal structure, Hirshfeld surface investigation and comparative DFT studies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate

The ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1), a thiazole ester, was synthesized by refluxing 1-(2-nitrobenzylidene)thiosemicarbazide and ethyl bromopyruvate. The compound is characterized by spectrometric, spectroscopic and single crystal (SC-XRD) techniques. Non-covalent interactions that are responsible for crystal packing are explored by Hirshfeld surface analysis. All theoretical calculations were performed by DFT quantum chemical methods using 6-311G(d,p) and cc-pVTZ basis sets and compared. Theoretical harmonic frequencies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) were optimized. Confirmation of hydrogen bonding sites was analyzed by molecular electrostatic potential (MEP) and Mulliken population analysis. The vibrational frequencies of characteristic functional groups and chemical shifts were found in good agreement with experimental assignments. Frontier molecular orbital (FMO) revealed relatively small HOMO–LUMO (highest occupied molecular orbital-lowest unoccupied molecular orbital) gape, which speaks off the nearly planar geometry and extended conjugation, as compared to the substituents with no conjugation possible. It has also been observed that –NO₂ substituent plays a vital role for this relatively small HOMO–LUMO gape and overall electronic properties when compared with similar thiazole carboxylates (2–6, Table 6). Ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) was also evaluated for its anti-oxidant and anti-microbial activities.

Synergistic impact of α-linolenic acid and α-tocopherol on in vitro maturation and culture of buffalo oocytes

The objective of the current study was to investigate the synergistic impact of α-Tocopherol and α-Linolenic acid (100 µM) on IVM and IVC of Nili Ravi buffalo oocytes. Oocytes were obtained from the ovaries of slaughtered buffaloes within two hours after slaughter and brought to laboratory. Buffalo cumulus oocyte complexes were placed randomly in the five experimental groups included; GROUP 1: Maturation media (MM) + 100 µM ALA (control), GROUP 2: MM + 100 µM ALA + 50μM α-Tocopherol, GROUP 3: MM + 100 µM ALA + 100μM α-Tocopherol, GROUP 4: MM + 100 µM ALA + 200 μM α-Tocopherol and GROUP 5: MM + 100 µM ALA + 300 μM α-Tocopherol under an atmosphere of 5% CO2 in air at 38.5 °C for 22-24 h. Cumulus expansion and nuclear maturation status was determined (Experiment 1). In experiment 2, oocytes were matured as in experiment 1. The matured oocytes were then fertilized in Tyrode's Albumin Lactate Pyruvate (TALP) medium for about 20 h and cultured in synthetic oviductal fluid (SOF) medium to determine effect of α-Linolenic acid (100 µM) and α-Tocopherol in IVM medium on IVC of presumptive zygotes. To study the effect of α-Linolenic acid (100 µM) in IVM media and increasing concentration of α-tocopherol in the culture media on early embryo development (Experiment 3), the presumptive zygotes were randomly distributed into the five experimental groups with increasing concentration of α-tocopherol in culture media. Higher percentage of MII stage oocytes in experiment 1(65.2±2.0), embryos at morula stage in experiment 2 (30.4±1.5) and experiment 3 (22.2±2.0) were obtained. However, overall results for cumulus cell expansion, maturation of oocyte to MII stage and subsequent embryo development among treatments remain statistically similar (P > 0.05). Supplementation of α-tocopherol in maturation media having α-Linolenic acid and/or in embryo culture media did not further enhance in vitro maturation of oocyte or embryo production.

Synthesis and In Silico Docking Studies of Ethyl 2-(2-Arylidene-1-Alkylhydrazinyl)Thiazole-4-Carboxylates as Antiglycating agents

Ethyl 2-(2-arylidene-1-alkylhydrazinyl)thiazole-4-carboxylates ( 1a-k ) were synthesized by alkylation on HN- of ethyl 2-(2-arylidenehydrazinyl)thiazole-4-carboxylates. The proposed structures ( 1a-k ) are corroborated by spectro-analytical techniques like UV, FT-IR, 1 H-, 13 C-NMR and HRMS. The compounds ( 1a-k ) were screened for their antiglycation and antioxidant assays. The in vitro antiglycation results revealed promising activity of compounds 1a , 1b , 1d , 1e , 1f , 1g , 1j and 1k with IC 50 values 0.0004 ± 1.097-17.22 ± 0.538 µM/mL when compared to standard, aminoguanidine (IC 50 = 25.50 ± 0.337 µM/mL). Among all tested compounds 1j and 1k are the best antiglycating agents with IC 50 values 1.848 ± 0.646 and 0.0004 ± 1.097 µM/mL, respectively. The in-silico studies also agree with these results where binding energy for 1j and 1k was found to be -9.25 and -8.42 kcal/mol with calculated dissociation constants of 0.16 and 0.67 µM. The antiglycation results demonstrate the application of these compounds in reducing diabetic complications.

Interaction of tacrolimus through hedgehog signaling pathway: An in vitro evaluation using rat hepatocytes

Tacrolimus (TAC) is the drug of choice in immunosuppressive therapy for organ transplantation; however, adverse effects are still a major concern. The current study aims to decipher the short-term exposure of TAC on rat hepatocytes in relation to activation of hedgehog (HH) signaling pathway. Time dependent study was conducted using primary rat hepatocytes treated with TAC (36 µM) for 6, 12, 24 and 48 h. Western blot analysis was performed using cell lysate in order to analyze the regulation of HH pathway proteins including HHIP, SMO, PTCH, IHH, SHH, and GLI transcription factors. The study revealed change in protein expression of HH signaling molecules with activation of HH pathway, due to downregulation of HHIP, and enrichment of HH ligands with activation of SMO and GLI transcription factors. It is therefore, concluded that short term TAC exposure leads to upregulation of HH pathway in liver, which may initially act to repair the liver damage but can worsen the condition in case of prolonged immunosuppressive therapy. This insight could lead to understand association of off target effects of immunosuppressive drugs and occurrence of other liver diseases in transplant patients when it comes to long term immunosuppressive therapy. These findings also illuminate a novel direction that use of HH inhibitor might provide a therapeutic strategy for immune suppression related liver disorders.

Synthesis, antioxidant, antimicrobial and antiviral docking studies of ethyl 2-(2-(arylidene)hydrazinyl)thiazole-4-carboxylates

A series of ethyl 2-(2-(arylidene)hydrazinyl)thiazole-4-carboxylates (2a-r) was synthesized in two steps from thiosemicarbazones (1a-r), which were cyclized with ethyl bromopyruvate to ethyl 2-(2-(arylidene)hydrazinyl)thiazole-4-carboxylates (2a-r). The structures of compounds (2a-r) were established by FT-IR, ¹H- and ¹³C-NMR. The structure of compound 2a was confirmed by HRMS. The compounds (2a-r) were then evaluated for their antimicrobial and antioxidant assays. The antioxidant studies revealed, ethyl 2-(2-(4-hydroxy-3-methoxybenzylidene)hydrazinyl)thiazole-4-carboxylate (2g) and ethyl 2-(2-(1-phenylethylidene)hydrazinyl)thiazole-4-carboxylate (2h) as promising antioxidant agents with %FRSA: 84.46 ± 0.13 and 74.50 ± 0.37, TAC: 269.08 ± 0.92 and 269.11 ± 0.61 and TRP: 272.34 ± 0.87 and 231.11 ± 0.67 μg AAE/mg dry weight of compound. Beside bioactivities, density functional theory (DFT) methods were used to study the electronic structure and properties of synthesized compounds (2a-m). The potential of synthesized compounds for possible antiviral targets is also predicted through molecular docking methods. The compounds 2e and 2h showed good binding affinities and inhibition constants to be considered as therapeutic target for M^pro protein of SARS-CoV-2 (COVID-19). The present in-depth analysis of synthesized compounds will put them under the spot light for practical applications as antioxidants and the modification in structural motif may open the way for COVID-19 drug.

In vivo assessment of bisphenol A induced histopathological alterations and inflammatory gene expression in lungs of male Wistar rats

Bisphenol A (BPA), an imperative environmental contaminant used in polycarbonate plastics. Due to limited information concerning the effect of BPA on lungs, this study design to assess whether BPA cause alterations in histopathology and trace metal content in lungs of rats. They were divided into five groups with five rats per group. Group I was named as control group. Group L6 and L12 were received BPA (10 mg/kg body weight/day) for 6 weeks and 12 weeks respectively. Group H6 and L12 were given BPA (25 mg/kg body weight/day) for 6 weeks and 12 weeks respectively. Considerable alteration in Cu, Zn and Fe was detected in experimental groups. BPA also caused significant increase in the expression of tumor necrosis factor α that mediate the pulmonary inflammatory response. Comparative study of resolved proteins i.e. 72 KDa (matrix metalloproteinase 2 fragment) and 109 KDa (nucleolin) on SDS-PAGE showed their altered expression in experimental groups. Histopathology of experimental groups revealed altered architecture of lungs. Special staining of BPA treated groups showed significant number of mast cells in alveoli and bronchioles. Prolonged administration of BPA causes deleterious aggravating lung damage even at extremely low dose, so the use of BPA should be prohibited in plastic synthesizing industries.

The design, synthesis, and in vitro trypanocidal and leishmanicidal activities of 1,3-thiazole and 4-thiazolidinone ester derivatives

Chagas and leishmaniasis are both neglected tropical diseases, whose inefficient therapies have made them remain the cause for millions of deaths worldwide. Given this, we synthesized 27 novel 1,3-thiazoles and 4-thiazolidinones using bioisosteric and esterification strategies to develop improved and safer drug candidates. After an easy, rapid and low-cost synthesis with satisfactory yields, compounds were structurally characterized. Then, in vitro assays were performed, against Leishmania infantum and Leishmania amazonensis promastigotes, Trypanosoma cruzi trypomastigotes and amastigotes, for selected compounds to determine IC₅₀ and SI, with cytotoxicity on LLC-MK2 cell lines. Overall, 1,3-thiazoles exhibited better trypanocidal activity than 4-thiazolidinones. The compound 1f, an ortho-bromobenzylidene-substituted 1,3-thiazole (IC₅₀ = 0.83 μM), is the most potent of them all. In addition, compounds had negligible cytotoxicity in mammalian cells (CC₅₀ values > 50 μM). Also noteworthy is the examination of the cell death mechanism of T. cruzi, which showed that compound 1f induced necrosis and apoptosis in the parasite. Scanning electron microscopy analysis demonstrated that the treatment of Trypanosoma cruzi trypomastigote cells with the compound 1f at different IC₅₀ concentrations promoted alterations in the shape, flagella and body surface, inducing parasite death. Together, our data revealed a novel series of 1,3-thiazole structure-based compounds with promising activity against Trypanosoma cruzi and Leishmania spp., broadening ways for scaffold optimization.

Chagas and leishmaniasis are both neglected tropical diseases, whose inefficient therapies have made them remain the cause for millions of deaths worldwide.

Subchronic toxicity of bisphenol A on the architecture of spleen and hepatic trace metals and protein profile of adult male Wistar rats

Bisphenol A (BPA) is one of the widely used chemical as a plasticizer and regarded as endocrine disruptor because of its ability to derail body metabolic functions and adverse effect on the vital organs. The present work outlined the subchronic effect of low-dose BPA (10 mg/kg) on histology of spleen, level of hepatic trace metals, and hepatic protein profile of Wistar rats. To conduct the research work, animals were grouped into two categories (n = 5). Group 1 was labelled as the control group and group 2 was taken as an experimental group. Experimental group was exposed to low-dose BPA for 12 weeks. Histopathology of spleen highlighted dilation in splenic sinuses, follicle activation, followed by depopulation in the area of white pulp and red pulp in the experimental group. Iron staining revealed significant hemosiderosis in the experimental group when compared with the control group. Statistically significant decrease was noted in zinc and copper concentrations, while nonsignificant change was observed for magnesium concentration through atomic absorption spectroscopy. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was run for hepatic protein profiling, and as compared to control, elevated levels of different proteins were observed in the experimental group. It can be concluded from the above results that even low dose of BPA causes changes in the major organs of the body. Hence, it is suggested that BPA alternative should be used, so that public health status can be secured.

Assessment and incidence of fish associated bacterial pathogens at hatcheries of Azad Kashmir, Pakistan

Fish is the most indispensable source of proteins for individuals and have high nutritional value. On the other hand, the fish culturing raised issues of fish health due to close contact between the aquatic environment and the fish pathogens. So, the aim of the current study was to identify the bacterial pathogens and screen the injured Rainbow trout rearing in different trout hatcheries run under fisheries department of the government of Azad Jammu and Kashmir, Pakistan. Seven bacterial pathogens such as Shigella flexneri, Enterobacter amnigenus, Salmonella Typhimurium, Serratia odorifera, Pseudomonas aeruginosa, Streptococcus pyogenes, and Bacillus cereus were isolated and identified. Results revealed that the injury of fish specimens was due to overcrowding. Instead of rainbow coloration, specimens have darker black in color. The water of ponds was not clean and clear and such conditions was because of the greater quantity of feed thrown in the water. It was concluded that poor hygienic water condition and overloading allowed the opportunistic bacterial contaminations to succeed which cause a serious threat to hatcheries.

Deciphering the mechanism of copper-catalyzed N-arylation between aryl halides and nitriles: a DFT study

The mechanism of the CuI/DMEDA-catalyzed tandem hydrolysis/N-arylation of benzonitrile with aryl iodide was studied using the DFT method.

Detection of rotavirus in paediatric oncology patients with diarrhoea: the impact of rotavirus vaccine

Seven years' data were reviewed to examine stool-testing for rotavirus in patents treated in a regional paediatric oncology unit before and after the introduction of UK-wide rotavirus immunization in July 2013. The prevalence of rotavirus positivity has diminished since the introduction of rotavirus immunization, with 21 of 416 positive samples between 2010 and 2012, but only one positive test out of 122 samples in 2015 and 2016. Based on these results, there seems to be little use for routine rotavirus-testing in children and young people with cancer presenting with diarrhoea.

Tacrolimus induced nephrotoxicity and pulmonary toxicity in Wistar rats

Transplantation has evolved into an accepted treatment for end-stage organ failure. The major limitation for solid organ transplantation is organ rejection, which is an adaptive immune response caused by the activation of T-cells. Immunosuppressant drugs are used to overcome this problem. Tacrolimus is a powerful immunosuppressive drug which is used to minimize the risk of organ rejection. The present study was designed to find the toxic effects of tacrolimus on lungs and kidneys. Wistar rats were divided into 4 experimental groups and one control group (n=9). Each rat of the experimental group was orally given the aqueous suspension of tacrolimus powder (3mg/ml) and dissected after 6, 12, 24 and 48 hours of tacrolimus suspension dose. Lungs and kidneys were excised and processed for histopathological and histochemical alterations. Kidney tissues presented signs of toxic potential on tissue architecture such as increased interstitial spaces, necrosis, especially acute tubular necrosis, glomerular shrinkage, dilated blood vessels and enlargement of Bowman’s capsule. Lung sections also confirmed the toxic potential, characterized by bronchiolar wall thickening, alveolar cells necrosis, collapsing of alveolar spaces and interstitial round cell infiltrate. Results of Prussian blue iron staining showed no iron deposition in kidney architecture while in lung sections, iron accumulation was evident. Taken together from these observations we can conclude that tacrolimus may induce toxicity to a certain extent with structural distortion of the kidneys and lungs.

Dose-dependent acute phase response of aqueous leaf decoction of Nerium oleander in Wistar rats

Many studies have been carried out in order to determine the toxicity of medicinal plants. The objective of this study was to compare and analyze the hepatic response against two doses of Nerium oleander, (N. oleander) “kaner” leaf decoction. Aqueous leaf decoction was injected intramuscularly into both hind limbs of male rats (200&#x2213;10g), assigned into three categories (n=4): control group with no treatment; group I, injected with 5 ml/ kg; and group II injected with 10 ml/ kg of leaf decoction, respectively. Animals were sacrificed 6 h after administration and hepato-histological changes were then observed. The decoction induced an acute phase reaction reflected by a more significant recruitment of inflammatory cells in group II than in group I and controls, as observed by histological studies. These results indicated that both doses can induce an acute-phase condition. Hence, traditional practice of medicinal plants without preliminary dose assessment must not be administered.

Effects of dietary supplementation of mannan-oligosaccharide on virus shedding in avian influenza (H9N2) challenged broilers

Avian influenza (AI) is a highly contagious disease causing significant economic losses worldwide. The aim of this study is to evaluate the effect of mannan-oligosaccharide (MOS) on tracheal and cloacal virus shedding in AI challenged broilers and contamination of environment with H₉N₂. A total of 300 1-day-old-broiler chicks were randomly divided into 3 groups (A, B and C) and supplemented 0.2, 0.5 and 0.0% MOS, respectively in NRC recommended diet for 36 days. On day 21 the groups were further split into two sub groups A+ve, A-ve, B+ve, B-ve, C+ve and C-ve with 5 replicates each. The positive groups were shifted to remote sheds and were challenged intranasally with 0.1 ml of reference virus (AIV; Pk-UDL/01/08 H₉N₂) with EID₅₀ = 10^-6.66. Treatment reduces (P<0.05) cloacal virus shedding from day 24 to 26 and 28 to 32. Tracheal virus shedding was lower (P<0.05) on days 25-26 and 28-30 in treatment groups. Day 27 showed highest (P>0.05) virus shedding in all groups. However the reduction of viral shedding is faster in treatment groups and showed no virus shedding on day 32. Maternal antibody titer against AI showed a declining pattern but MOS influenced (P<0.05) the titer in treated groups. Hence the use of MOS may constitute a novel and effective plausible alternative that reduces the spread of disease by decreasing virus shedding and contamination of environment from AIV (H₉N₂) infection in poultry.

Crystal structure of (E)-2-(4-chloro-benzyl-idene)-3,4-di-hydro-naphthalen-1(2H)-one: a second monoclinic polymorph

The title compound, C17H13ClO, is the second monoclinic polymorph to crystallize in the space group P21/c. The first polymorph crystallized with two independent mol-ecules in the asymmetric unit [Bolognesi et al. (1975 ▸). Acta Cryst. A31, S119; Z' = 2; no atomic coordinates available], whereas the title compound has Z' = 1. In the title polymorph, the dihedral angle between the plane of the benzene ring of the tetra-lone moiety and that of the 4-chloro-benzyl ring is 52.21 (11)°. The cyclo-hex-2-en-1-one ring of the tetra-lone moiety has a screw-boat conformation. In the crystal, mol-ecules are liked by pairs of C-H⋯π inter-actions forming inversion dimers. There are no other significant inter-molecular inter-actions present.

Pharmacological justification of use of Solena heterophylla Lour. in gastrointestinal, respiratory and vascular disorders

Background

Solena heterophylla Lour. has traditionally been used in the management of diseases pertaining to gastrointestinal, respiratory and vascular system and present study was undertaken to validate its traditional uses.

Methods

The aqueous ethanolic extract of Solena heterophylla Lour (Sh.Cr) was tested in-vitro on isolated rabbit jejunum, tracheal and aorta preparations. The responses of tissues were recorded using isotonic transducers coupled with PowerLab data acquisition system.

Results

The aqueous ethanolic extract of Solena heterophylla Lour (Sh.Cr) (0.03-1.0 mg/ml) on application to spontaneous contractions in isolated rabbit jejunum preparation exerted relaxant effect through decrease in magnitude and frequency of contractions, caused relaxation of K⁺(80 mM)-induced contractions and shifted the Ca²⁺ concentration response curves toward right in isolated rabbit jejunum preparations in a manner similar to verapamil (a standard Ca²⁺ channel blocker), thus confirming its Ca²⁺ channel blocking activity. The Sh.Cr also caused relaxation of carbachol (1 μM)- and K⁺(80 mM)-induced contractions in isolated rabbit tracheal preparations in a manner comparable to dicyclomine.

Conclusions

The observed relaxant effect may be outcome of anti-muscarinic and Ca²⁺ channel blocking activities. The Sh.Cr (0.03-1.0 mg/ml) against phenyephrine (1 μM)- and K⁺(80 mM)-induced contractions in isolated rabbit aortic preparations exerted a relaxant effect, possibly through Ca²⁺ channel blocking activity. These findings provide a rationale for the folkloric uses of the plant in the management of ailments pertaining to gastrointestinal, respiratory and vascular system.

New Aryl-1,3-thiazole-4-carbohydrazides, Their 1,3,4-Oxadiazole-2- thione, 1,2,4-Triazole, Isatin-3-ylidene and Carboxamide Derivatives. Synthesis and Anti-HIV Activity

A series of isatin-3-ylidene (6a-i) and arylthiazolyl-1,3,4-oxadiazole-2-thione derivatives 7a-i derived from arylthiazolyl carbohydrazide analogs 4a-i were synthesized. Analogously, coupling of 4f with various amino acid methyl esters in the presence of HOBt/DCC reagents afforded the carboxamide derivatives 9a-d. The newly synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. All compounds are inactive, except compounds 9b and 9c which showed inhibition of HIV-1 with EC50 = 2:34 μg mL-1, and 1.12 μg mL-1 with therapeutic indexes (SI) of 9 and <1, respectively.

Synthesis, Crystal Structure and Antiproliferative Activity of 6-Adamantyl-3-aryl[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles

A series of 3,6-disubstituted [1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 5a - l bearing an adamantyl moiety were synthesized by condensation of 4-amino-5-aryl-2H-1,2,4-triazole-3(4H)-thiones 4a -l with adamantyl-1-carboxylic acid in the presence of POCl3. The structures of the newly synthesized compounds were established using spectroanalytical techniques and verified further by the crystal structure determination of compounds 5a and 5j. The compounds were screened for their antiproliferative activity against a large panel of human cell lines.

Community participation eludes Pakistan's maternal, newborn and child health programme

This study looked at the comprehensiveness of the primary health care approach being applied in Pakistan's National Maternal, Newborn and Child Health (MNCH) Programme launched in 2005. The methods included a review of the programme's guideline documents, in-depth interviews with managers/advisors and focus group discussions with community groups and service providers. The MNCH Programme is applying a selective primary care model. Programme advisors and managers were concerned about the quality of training, political interference and incomplete implementation. Service providers were not working together as envisioned. Community midwives complained about the community's perceptions of them. Community members were unaware of MNCH Programme implementation in their areas. Pakistan's primary health care programme needs to be reviewed and revised according current thinking on community participation and inter-sectoral collaboration to accelerate progress towards achievement of Millennium Development Goals 4 and 5.

Synthesis, crystal structure and anti-HIV activity of 2-adamantyl/adamantylmethyl-5-aryl-1,3,4-oxadiazoles

Two series of 2-adamantyl/adamantylmethyl-5-aryl-1,3,4-oxadiazoles (4a-l and 5a-l) were synthesized by cyclodehydration of adamantan-1-carboxylic acid/adamantylacetic acid with various aryl hydrazides (3a-l) in the presence of POCl(3). The synthesis was supported by spectroanalytical techniques and verified further by crystal structure determination of compounds 4e and 5k. The synthesized compounds were screened for their inhibitory activity against HIV-1 and HIV-2 in MT-4 cells. Compound 5b exhibited a moderate activity in vitro for the replication of both virus types, suggesting for further structural modification as a new lead in the development of an antiviral agent.

Amine-linked diglycosides: Synthesis facilitated by the enhanced reactivity of allylic electrophiles, and glycosidase inhibition assays

Diglycose derivatives, consisting of two monosaccharides linked at non-anomeric positions by a bridging nitrogen atom, have been synthesised. Conversion of one of the precursor monosaccharide coupling components into an unsaturated derivative enhances its electrophilicity at the allylic position, facilitating coupling reactions. Mitsunobu coupling between nosylamides and 2,3-unsaturated-4-alcohols gave the 4-amino-pseudodisaccharides with inversion of configuration as single regio- and diastereoisomers. A palladium-catalysed coupling between an amine and a 2,3-unsaturated 4-trichloroacetimidate gave a 2-amino-pseudodisaccharide as the major product, along with other minor products. Derivatisation of the C=C double bond in pseudodisaccharides allowed the formation of Man(N4–6)Glc and Man(N4–6)Man diglycosides. The amine-linked diglycosides were found to show weak glycosidase inhibitory activity.

6-(Adamantan-1-yl)-3-(3-fluoro-phen-yl)-1,2,4-triazolo[3,4-b][1,3,4]thia-diazole

The title mol­ecule, C₁₉H₁₉FN₄S, displays C_s mol­ecular symmetry, in which the crystallographic mirror plane bis­ects the adamantan-1-yl unit while the 3-fluoro­phenyl triazole ring is located on the mirror plane. The F atom of the 3-fluoro­phenyl ring is positionally disordered [occupancy ratio 0.9:0.1]. In the crystal, π–π inter­actions between the triazole and phenyl rings occur [centroid–centroid distance = 3.5849 (7) Å] and weak C—H⋯F inter­actions form a ribbon propagating in [010].