5 research outputs found
Synthesis and pharmacological evaluation of N-{4-[2-(4-arylpiperazin-1-yl) ethyl] phenyl}arylamides
Serotonin 5HT1a receptor belongs to a class of G-protein coupled receptors. It serves as a
potential target for neurological disorders such as depression, anxiety etc. It is a well-known
fact that N-arylpiperazine moiety is present in compounds with pronounced 5HT1a activity.
Taking into account previously published results1
novel structures of N-{4-[2-(4-
arylpiperazin-1-yl)ethyl]phenyl}arylamides (Figure 1.) were designed for target synthesis.
Proposed modifications include: different position of hydroxyl group in aryl amide part of
molecule and addition of methoxy and chloro substituents to the phenyl ring of parent
compounds, since their introduction in the molecule leads to increased receptor affinity.
New compounds were synthesized by acylation of N-arylpiperazines using 4-
nitrophenylacetic acid. Obtained amides were converted in 1-(4-nitrophenethyl)-4-
arylpiperazines using diborane in THF. Reduction of nitro compounds by Ra/Ni provided 1-
(4-aminophenethyl)-4-arylpiperazines. Target arylamides were obtained by condensation 1-
(4-aminophenethyl)-4-arylpiperazines with corresponding aryl acids in presence of
propylphosphoric acid anhydride (PPAA) in DMF.
All newly synthesized compounds were evaluated for their activity toward 5HT1a receptors
by in vitro competitive displacement assay of [3H] 8-OH-DPAT. HEK cell line were used as a
source of 5HT1a receptors.
Introduction of 2-methoxy and 2,3-dichloro groups,as well as meta and para hydroxyl group
in molecule resulted in increment of affinity toward 5HT1a receptors comparing to the parent
compounds
Design, synthesis and pharmacological evaluation of N-{4-[2-(4-aryl-piperazin-1-yl)-ethyl]-phenyl}-arylamides
5HT1A receptor targeting drugs have been used as the treatment for the many neuropsychiatric
disorders, such as schizophrenia and depression. As a part of ongoing research, we designed series of
new compounds that share arylpiperazine common structural motif with the 5HT1A receptor ligand
aripiprazole. Receptor-ligand interactions were determined by the molecular docking simulations,
revealing the positive impact of the phenyl substitution in the arylpiperazine part of the molecules. Nine
selected compounds were synthesized in four reaction steps in high overall yields (59-73%). In vitro
pharmacological evaluation of the synthesized compounds revealed three compounds (5b, 6b and 6c)
with high 5HT1A binding affinity, comparable with aripiprazole (Ki 12.0, 4.8, 12.8, 5.6 nM,
respectively). Compounds from b series, 5b and 6b, possess 2-methoxyphenyl substituents, while 6c
possess 2,3-dichlorophenyl substituent in the arylpiperazine part of the molecule. The pharmacological
results are therefore in accordance with the molecular docking simulations thus proving the rational
design. Compounds 5c, 6b and 6c can be considered as the candidates for further evaluation as new,
potential antidepressants
Synthesis of novel 5-HT1A arylpiperazine ligands: Binding data and computer-aided analysis of pharmacological potency
Serotonin receptors modulate numerous behavioral and neuropsychological processes. Therefore, they are the target for the action of many drugs, such as antipsychotics, antidepressants, antiemetics, migraine remedies, and many others. The 5-HT1A receptors have been involved in the pathogenesis and treatment of anxiety and depression and represent a promising target for new drugs with reduced extrapyramidal side effects. In most antidepressants, a piperazine-based structural motif can be identified as a common moiety. Here we describe the synthesis, pharmacological, and in silico characterization of a novel arylpiperazines series with excellent 5-HT1A affinity. The final compounds, 4a, 8a, and 8b, were selected according to predictions of in silico pharmacokinetics, docking analysis, and molecular dynamics in conjunction with physical properties, and metabolic stability. The accentuated molecules could serve as a lead compound for developing 5-HT1A drug-like molecules for depression treatment
Development of fluorinated indanone-based derivatives for the imaging of monoamine oxidase B via positron emission tomography
Ziel/Aim The monoamine oxidase B (MAO B) isoenzyme is known to be
involved in the oxidative deamination of biogenic amines. While the use of
MAO B inhibitors is already well-established for the treatment of Parkinsonās
disease, recent reports suggest its involvement in certain types of brain
tumors.1 We herein aim at the synthesis and preclinical evaluation of fluorinated indanone-based derivatives targeting MAO B in the brain via positron
emission tomography (PET).
Methodik/Methods A small series of fluorinated indanone derivatives
was obtained via the O-alkylation or esterification starting with the
commercially available 6-hydroxy-2,3-dihydro-1H-inden-1-one in one or
two steps. Binding affinities towards the human MAO isoenzymes were
estimated in vitro by radioligand displacement. HL126 was selected for
radiofluorination via its corresponding boronic acid pinacol ester. In
vitro autoradiography of [18F]HL126 was performed in mice brain slices.
In vivo evaluation of [18F]HL126 in CD-1 mice was carried out and
metabolism studies were performed in plasma and brain samples via
radio-HPLC.
Ergebnisse/Results The fluorinated indanone derivatives were synthesized
in yields ranging from 65-89 %. The fluorophenyl ether derivative, HL126,
was further selected for radiofluorination based on its high binding affinity
towards MAO B (Ki = 6.9 Ā± 5.3 nM). [18F]HL126 was obtained by an alcohol-enhanced copper-mediated approach via the corresponding boronic
acid pinacol ester precursor with radiochemical yields of about 11 Ā± 3 %,
high radiochemical purities (ā„99 %) and molar activities in the range of 20
GBq/mmol. In vitro autoradiography showed a specific blockade with
selective MAO-A/B inhibitors. PET/MRI analyses revealed that [18F]HL126
readily enters the brain. Some radiometabolites do cross the blood-brain
barrier.
Schlussfolgerungen/Conclusions Although metabolism studies with [18F]
HL126 revealed the presence of radiometabolites in the brain, the high binding affinity towards MAO B and the pronounced selectivity in in vitro autoradiography studies encourage further derivatization of indanone-based
scaffolds for targeting MAO B
Multi-target potential of newly designed tacrine-derived cholinesterase inhibitors: Synthesis, computational and pharmacological study
Simple and scalable synthetic approach was used for the preparation of thirteen novel tacrine derivatives consisting
of tacrine and N-aryl-piperidine-4-carboxamide moiety connected by a five-methylene group linker. An
anti-Alzheimer disease (AD) potential of newly designed tacrine derivatives was evaluated against two important
AD targets, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). In vitro pharmacological evaluation
showed strong ChE inhibitory activity of all compounds, with IC50 values ranging from 117.5 to 455 nM for AChE
and 34 to 324 nM for BuChE. As a representative of the series with the best cytotoxicity / ChE inhibitory activity
ratio, expressed as the selectivity index (SI), 2-chlorobenzoyl derivative demonstrated mixed-type inhibition on
AChE and BuChE, suggesting binding to both CAS and PAS of the enzymes. It also exhibited antioxidant capacity
and neuroprotective potential against amyloid-Ī² (AĪ²) toxicity in the culture of neuron-like cells. In-depth
computational analysis corroborated well with in vitro ChE inhibition, illuminating that all compounds exhibit
significant potential in targeting both enzymes. Molecular dynamics (MD) simulations revealed that 2-chlorobenzoyl
derivative, created complexes with AChE and BuChE that demonstrated sufficient stability throughout the
observed MD simulation. Computationally predicted ADME properties indicated that these compounds should
have good bloodābrain barrier (BBB) permeability, an important factor for CNS-targeting drugs. Overall, all
tested compounds showed promising pharmacological behavior, highlighting the multi-target potential of 2-
chlorobenzoyl derivative which should be further investigated as a new lead in the drug development process