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Chemosphere Nov 2022Purification of Natural gas is vital for utilizing it as a source of energy harvesting for the world. Amine-based chemical absorption technique is the most utilized in...
Purification of Natural gas is vital for utilizing it as a source of energy harvesting for the world. Amine-based chemical absorption technique is the most utilized in the gas field for the purification of gas that ensures the purity of the sweet gas stream with the elimination of carbon dioxide. However, it is considered an energy-intensive process to deal with considerable energy loss and environmental damage to the ecosystem. Five cases have been developed in this study based on various blends comprising mono and tertiary amines in combination with piperazine with a focus on the use of Aqueous Monodiethanolamine (Aq. MDEA), Aqueous Monoethanolamine (Aq. MEA) and piperazine (Pz) for the CO sequestration from the sour natural gas extracted from the remote location located in the province of Baluchistan in Pakistan. The use of exergy, advanced exergy, and exergo environment for optimizing and selecting a suitable solvent combination that may result in an effective separation process has been proposed. Five cases have been developed based on various blends such as mono and tertiary amines combined with piperazine. From the results of all the studied scenarios, Case IV, based on the combination of Aqueous monoethanolamine and piperazine, provides reduced exergy destruction of 2551.7 KW. It was observed that the maximum removal of CO around 99.87 wt% is achieved in case IV. In addition, advance exergy analysis also highlights that case-IV has a venue of 25% exergy destruction avoidable, which would further enhance its performance. Nevertheless, still, case-IV has 75% exergy destruction unavoidable. The environmental factors show that Case-IV has a reduced exergy destruction factor of 0.96, a highly environmentally benign choice as a solvent with a high value of 1.03, and case-IV has the higher operational stability and higher exergy efficiency with an exergy stability value of 0.40. Therefore, monoethanolamine combined with piperazine to be an effective and efficient solvent blend that could be an energy-effective approach for sweetening the natural gas.
Topics: Amines; Carbon Dioxide; Ecosystem; Ethanolamine; Natural Gas; Piperazine; Solvents; Water
PubMed: 35987263
DOI: 10.1016/j.chemosphere.2022.136001 -
Environmental Science and Pollution... Jan 2022In this study, activated carbon and piperazine-modified activated carbon adsorbents were prepared and used for CO adsorption. The effect of various parameters including...
In this study, activated carbon and piperazine-modified activated carbon adsorbents were prepared and used for CO adsorption. The effect of various parameters including adsorbent particle size, adsorbent amount, piperazine weight percent, pressure, and temperature were investigated on the CO adsorption capacity. The adsorbents were characterized using nitrogen adsorption/desorption isotherms and FTIR analyses. The results showed that the adsorption capacity decreases with temperature increasing and increases with pressure increasing. In addition, the surface modification of activated carbon improved the CO adsorption capacity more than the unmodified adsorbent, and the highest CO adsorption was obtained 203.842 mg/g at 25 °C and 8 bar. Additionally, to determine the adsorbent behavior, CO adsorption experimental data were fitted by isotherm and kinetic models. CO adsorption isotherm modeling was studied up to 8 bar at 25 °C, and kinetic modeling was investigated up to 85 °C at 6 bar. The results show that Hill isotherm model and Elovich kinetic models have a good agreement with the adsorption data. Finally, thermodynamic modeling was carried out for modified and unmodified adsorbents, and enthalpy, entropy, and Gibbs free energy changes of adsorption for piperazine-modified activated carbon at 25 °C and 6 bar obtained 17.078 kJ/mol, - 0.039 kJ/mol.K, and - 5.318 kJ/mol, respectively.
Topics: Adsorption; Carbon Dioxide; Charcoal; Kinetics; Nitrogen; Piperazine; Thermodynamics
PubMed: 34417695
DOI: 10.1007/s11356-021-16040-5 -
Carbohydrate Research Jul 2023To imbibe the aim of synthesizing water-soluble and biocompatible motif, a click-inspired piperazine glycoconjugate has been devised up. In this report, we present a...
To imbibe the aim of synthesizing water-soluble and biocompatible motif, a click-inspired piperazine glycoconjugate has been devised up. In this report, we present a focused approach to design and synthesis of versatile sugar-appended triazoles through 'Click Chemistry' along with their pharmacological studies on cyclin-dependent kinases (CDKs) and cell cytotoxicity on cancer cells using in silico and in vitro approaches, respectively. The study has inclusively recognized the galactose- and mannose-derived piperazine conjugates as the promising motifs. The findings suggested that the galactosyl bis-triazolyl piperazine analogue 10b is the most CDK interactive derivative and also possess significant anticancer activity.
Topics: Piperazine; Sugars; Click Chemistry; Glycoconjugates; Galactose; Antineoplastic Agents
PubMed: 37245419
DOI: 10.1016/j.carres.2023.108846 -
Molecules (Basel, Switzerland) Dec 2023The piperazine moiety is often found in drugs or in bioactive molecules. This widespread presence is due to different possible roles depending on the position in the... (Review)
Review
The piperazine moiety is often found in drugs or in bioactive molecules. This widespread presence is due to different possible roles depending on the position in the molecule and on the therapeutic class, but it also depends on the chemical reactivity of piperazine-based synthons, which facilitate its insertion into the molecule. In this paper, we take into consideration the piperazine-containing drugs approved by the Food and Drug Administration between January 2011 and June 2023, and the synthetic methodologies used to prepare the compounds in the discovery and process chemistry are reviewed.
Topics: United States; Piperazine; United States Food and Drug Administration
PubMed: 38202651
DOI: 10.3390/molecules29010068 -
Bioorganic & Medicinal Chemistry Letters Aug 2018We have developed versatile methods toward the synthesis of a variety of piperidine/piperazine bridged isosteres of pridopidine. The compounds were assessed against the...
We have developed versatile methods toward the synthesis of a variety of piperidine/piperazine bridged isosteres of pridopidine. The compounds were assessed against the D2 receptor in agonist and antagonist modes and against the D4 receptor in agonist mode. hERG Binding and the ADME profiles were studied.
Topics: Animals; Bridged Bicyclo Compounds; Crystallography, X-Ray; Dopamine Antagonists; Drug Design; ERG1 Potassium Channel; Humans; Magnetic Resonance Spectroscopy; Mice; Piperazine; Piperidines; Receptors, Dopamine D2; Receptors, Dopamine D4; Structure-Activity Relationship
PubMed: 29937060
DOI: 10.1016/j.bmcl.2018.06.038 -
ACS Chemical Neuroscience Jun 2023Our present work demonstrates the successful design and synthesis of a new class of compounds based upon a multitargeted directed ligand design approach to discover new...
Design, Synthesis, and Biological Evaluation of Piperazine and -Benzylpiperidine Hybrids of 5-Phenyl-1,3,4-oxadiazol-2-thiol as Potential Multitargeted Ligands for Alzheimer's Disease Therapy.
Our present work demonstrates the successful design and synthesis of a new class of compounds based upon a multitargeted directed ligand design approach to discover new agents for use in Alzheimer's disease (AD). All the compounds were tested for their in vitro inhibitory potential against human acetylcholinesterase (hAChE), human butylcholinesterase (hBChE), β-secretase-1 (hBACE-1), and amyloid β (Aβ) aggregation. Compounds and have shown hAChE and hBACE-1 inhibition comparable to donepezil, while hBChE inhibition was comparable to rivastigmine. Compounds and also demonstrated a significant reduction in the formation of Aβ aggregates through the thioflavin T assay and confocal, atomic force, and scanning electron microscopy studies and significantly displaced the total propidium iodide, that is, 54 and 51% at 50 μM concentrations, respectively. Compounds and were devoid of neurotoxic liabilities against RA/BDNF (RA = retinoic acid; BDNF = brain-derived neurotrophic factor)-differentiated SH-SY5Y neuroblastoma cell lines at 10-80 μM concentrations. In both the scopolamine- and Aβ-induced mouse models for AD, compounds and demonstrated significant restoration of learning and memory behaviors. A series of ex vivo studies of hippocampal and cortex brain homogenates showed that and elicit decreases in AChE, malondialdehyde, and nitric oxide levels, an increase in glutathione level, and reduced levels of pro-inflammatory cytokines, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) mRNA. The histopathological examination of mice revealed normal neuronal appearance in the hippocampal and cortex regions of the brain. Western blot analysis of the same tissue indicated a reduction in Aβ, amyloid precursor protein (APP)/Aβ, BACE-1, and tau protein levels, which were non-significant compared to the sham group. The immunohistochemical analysis also showed significantly lower expression of BACE-1 and Aβ levels, which was comparable to donepezil-treated group. Compounds and represent new lead candidates for developing AD therapeutics.
Topics: Humans; Mice; Animals; Alzheimer Disease; Donepezil; Amyloid beta-Peptides; Ligands; Brain-Derived Neurotrophic Factor; Piperazine; Acetylcholinesterase; Neuroblastoma; Cholinesterase Inhibitors; Structure-Activity Relationship
PubMed: 37216500
DOI: 10.1021/acschemneuro.3c00245 -
International Journal of Molecular... Dec 2023Thiazole and piperazine are two important heterocyclic rings that play a prominent role in nature and have a broad range of applications in agricultural and medicinal...
Thiazole and piperazine are two important heterocyclic rings that play a prominent role in nature and have a broad range of applications in agricultural and medicinal chemistry. Herein, we report the parallel synthesis of a library of diverse piperazine-tethered thiazole compounds. The reaction of piperazine with newly generated 4-chloromethyl-2-amino thiazoles led to the desired piperazine thiazole compounds with high purities and good overall yields. Using a variety of commercially available carboxylic acids, the parallel synthesis of a variety of disubstituted 4-(piperazin-1-ylmethyl)thiazol-2-amine derivatives is described. the screening of the compounds led to the identification of antiplasmodial compounds that exhibited interesting antimalarial activity, primarily against the chloroquine-resistant Dd2 strain. The hit compound demonstrated an antiplasmodial EC of 102 nM in the chloroquine-resistant Dd2 strain and a selectivity of over 140.
Topics: Antimalarials; Piperazine; Thiazoles; Chloroquine; Plasmodium falciparum
PubMed: 38139243
DOI: 10.3390/ijms242417414 -
Expert Opinion on Therapeutic Patents Jul 2016Piperazine, a six membered nitrogen containing heterocycle, is of great significance to the rational design of drugs. This moiety can be found in a plethora of... (Review)
Review
INTRODUCTION
Piperazine, a six membered nitrogen containing heterocycle, is of great significance to the rational design of drugs. This moiety can be found in a plethora of well-known drugs with various therapeutic uses, such as antipsychotic, antihistamine, antianginal, antidepressant, anticancer, antiviral, cardio protectors, anti-inflammatory, and imaging agents. Slight modification to the substitution pattern on the piperazine nucleus facilitates a recognizable difference in the medicinal potential of the resultant molecules.
AREAS COVERED
Scifinder was the main source used to search for patents containing piperazine compounds with therapeutic uses. The article describes a variety of molecular designs bearing piperazine entity furnishing CNS agents, anticancer, cardio-protective agents, antiviral, anti-tuberculosis, anti-inflammatory, antidiabetic, and antihistamine profiles, as well as agents relieving pain and useful in imaging applications.
EXPERT OPINION
The great interest gathered to explore piperazine based molecules in relatively few years reflects the broad potential of the entity. Earlier, this scaffold was considered to express CNS activity only. However, a significant increase in research covering studies of several different activities of piperazine ring suggest a successful emergence of the pharmacophore. Certain patents outlined in the present article recommend that piperazines can be a flexible building block to discover drug-like elements and modification of substituents present on the piperazine ring may have a significant impact on the pharmacokinetic and pharmacodynamics factors of the resulting molecules. This article aims to provide insights to piperazine based molecular fragments that would assist drug discoverers to rationally design molecules for various diseases. We anticipate, and highly recommend, further therapeutic investigations on this motif.
Topics: Animals; Drug Design; Drug Discovery; Humans; Patents as Topic; Piperazines; Structure-Activity Relationship
PubMed: 27177234
DOI: 10.1080/13543776.2016.1189902 -
Drug Development Research Dec 2018Hit, Lead & Candidate Discovery After acetylcholine is released into the synaptic cleft, it is reabsorbed or deactivated by acetylcholinesterase (AChE). Studies on...
Hit, Lead & Candidate Discovery After acetylcholine is released into the synaptic cleft, it is reabsorbed or deactivated by acetylcholinesterase (AChE). Studies on Alzheimer's disease (AD) in the mid-20th century proved that cognitive dysfunctions are associated with cholinergic neurotransmission. Drugs, such as tacrine, rivastigmine, donepezil, and galantamine are known as acetylcholinesterase inhibitors. However, these drugs have limited use in advanced AD and dementia. Recently, the anticholinesterase activity of various heterocyclic-framed compounds, including piperazine derivatives, has been investigated, and compounds with similar effects to known drugs have been identified. The aim of this study was to design new donepezil analogs. In this study, 66 original piperazinyl thiazole derivatives were synthesized by the reaction of piperazine N'-benzoyl thioamides and bromoacetophenones to inhibit AChE. Biological activity was measured by the Ellman method. Compounds 35, 38, 40, 45, 57, and 61 showed a high inhibitory effect among the series (80.36%-83.94% inhibition), and donepezil had a 96.42% inhibitory effect. The IC values of compounds 35, 38, and 40, were calculated as 0.9767 μM, 0.9493 μM, and 0.8023 μM, respectively. Compound 45 (IC = 1.122), Compound 57 (IC = 1.2130) and 61 (IC = 0.9193) also exhibited good activity on AChE. Molecular modeling studies were in agreement with the predictions. Trp286, Arg296, and Tyr341 were the key amino acids at the active site. Both donepezil and synthesized compounds seemed to interact with these residues.
Topics: Acetylcholinesterase; Cholinesterase Inhibitors; Donepezil; Humans; Models, Molecular; Molecular Docking Simulation; Piperazine; Thiazoles
PubMed: 30343499
DOI: 10.1002/ddr.21481 -
Journal of Inorganic Biochemistry Apr 2023Rigidification of the ligand scaffolds has been a particular mechanism of interest employed to achieve properties suitable for MRI contrast, catalysis, or other...
Rigidification of the ligand scaffolds has been a particular mechanism of interest employed to achieve properties suitable for MRI contrast, catalysis, or other applications of metal complexes. Towards the goal of targeting a 15-anePyNPip type ligand, a serendipitous isolation of a 30-anePyNPip aza-macrocycle was achieved, instead. X-ray diffraction and determination of pK events were carried out and compared to 17-anePyNPip. Furthermore, the X-ray diffraction of the Cu(II) and Zn(II) complexes of 17-anePyNPip was achieved and compared to previous reports of other first-row transition metal derivatives of this ligand. Determination of the log β with both 30-anePyNPip and 17-anePyNPip with the divalent MnZn metal-ion series was used to demonstrate the impact that the piperazine ring plays compared to other, less rigid macrocycles reported to date.
Topics: Coordination Complexes; Piperazine; Ligands; Molecular Structure; Transition Elements
PubMed: 36652846
DOI: 10.1016/j.jinorgbio.2023.112124