Anna Czopek

Synthesis and anticonvulsant activity of new N-Mannich bases derived from 5-cyclopropyl-5-phenyl- and 5-cyclopropyl-5-(4-chlorophenyl)-imidazolidine-2,4-diones

Synthesis, physicochemical and anticonvulsant properties of new N-Mannich bases derived from 5-cyclopropyl-5-phenyl- and 5-cyclopropyl-5-(4-chlorophenyl)-imidazolidine-2,4-diones have been described. Initial anticonvulsant screening was performed using intraperitoneal (ip.) maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure tests. The neurotoxicity was determined applying the rotarod test. The in vivo results in mice showed that all compounds were effective especially in the MES screen. The quantitative evaluation after oral administration in rats showed that the most active was 5-cyclopropyl-5-phenyl-imidazolidine-2,4-dione (1) with ED(50) values of 5.76 mg/kg (MES) and 57.31 mg/kg (scPTZ). This molecule was more potent than phenytoin and ethosuximide which were used as reference antiepileptic drugs. Additionally compound 1 with ED(50) of 26.06 mg/kg in psychomotor seizure test (6-Hz) in mice showed comparable activity to new generation anticonvulsant - levetiracetam.

Synthesis and Anticonvulsant Activity of New N-Mannich Bases Derived from 5-Cyclopropyl-5-phenyl-hydantoins

Synthesis, physicochemical and anticonvulsant properties of new N‐Mannich bases 3–24 derived from 5‐cyclopropyl‐5‐phenyl‐ and 5‐cyclopropyl‐5‐(4‐chlorophenyl)‐hydantoins were described here. Initial anticonvulsant screening was performed using intraperitoneal (i.p.) maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizures tests. Selected derivatives were also screened in the 6‐Hz test. The neurotoxicity was determined applying the rotorod test. The pharmacological results revealed that the majority of compounds were effective in MES and/or scPTZ tests. The quantitative studies after oral administration into rats showed that several molecules were more potent than phenytoin and ethosuximide which were used as reference antiepileptic drugs. From the whole series the most active was 3‐[(4‐phenylpiperazin‐1‐yl)‐methyl]‐5‐cyclopropyl‐5‐phenyl‐imidazolidine‐2,4‐dione (3) with the ED50 value of 5.29 mg/kg in the MES test.

Novel Mannich Bases, 5‐Arylimidazolidine‐2,4‐dione Derivatives with Dual 5‐HT1A Receptor and Serotonin Transporter Affinity

A computer aided ligand design study of imidazolidine‐2,4‐dione derivatives was conducted in order to obtain compounds with dual 5‐HT1A receptor and serotonin transporter (SERT) affinity. According to molecular modeling results, series of Mannich bases were chosen and synthesized. Investigated compounds were tested for 5‐HT1A, 5‐HT2A, α1 and SERT affinity. Two selected compounds (5, 9) were characterized in functional experiments and possessed a pharmacological profile which may enhance SERT blocking efficacy – 5‐HT1A partial agonism and 5‐HT2A antagonism in one molecule. Furthermore these compounds displayed satisfactory selectivity over adrenergic α1 receptors. The most promising compounds, 5‐arylimidazolidine‐2,4‐dione derivatives with 4‐(3‐chlorophenyl)piperazinylmethyl moiety were tested for antidepressant and anxiolytic activity. In particular, compound 5 (5‐(2‐methoxyphenyl)‐3‐{1‐[4‐(3‐chlorophenyl)piperazin‐1‐yl]methyl}‐imidazolidine‐2,4‐dione), tested in the forced swim test in mice, exhibited a favorable antidepressant‐like profile without affecting spontaneous locomotor activity.

The Lipophilicity Estimation of Selected Dermatological Drugs Using Micellar Electrokinetic Chromatography Method

Lipophilicity is a key physicochemical property which affects pharmacokinetic and pharmacodynamics processes of a drug. This parameter is particularly important for dermatological drugs which should penetrate through the skin barrier. Micellar electrokinetic chromatography (MEKC) method was applied for determination of lipophilicity of salicylic acid and antibiotics commonly used in dermatology. The results of MEKC analysis were compared to lipophilicity coefficients determined by reversed-phase thin-layer chromatography (RM0) and computational (AlogPs, AClogP, logPPallas) methods using principal component analysis (PCA). Thanks to PCA method, a high correlation between the results obtained by both experimental: parameters (logk (MEKC) and RM0 (RP-TLC)) was observed, but the relationship between them and results of the theoretical values were poor.

Serotonin transporter activity of imidazolidine-2,4-dione and imidazo[2,1-f]purine-2,4-dione derivatives in aspect of their acid–base properties

Affinities of arylpiperazinylalkyl derivatives of imidazo[2,1-f]purine-2,4-dione and imidazolidine-2,4-dione for serotonin transporter and their acid–base properties were evaluated. The dissociation constant (pKa) of compounds 1–22 were determinated by potentiometric titration and calculated using pKalc 3.1 module of the Pallas system. The data from experimental methods and computational calculations were compared and suitable conclusions were reached.

Determination of ligand efficiency indices in a group of 7H-purine-2,6-dione derivatives with psychotropic activity using micellar electrokinetic chromatography

Discovering hit compounds and optimization processes in medicinal chemistry nowadays could be improved by predictive tools, based on the relationship between structure of molecules and lipophilic properties. Lipophilicity of drug candidate can affect both the pharmacokinetic and pharmacodynamics properties, in particular, the ability of a molecule to cross the cell membrane. Among the new methods for determination of the lipophilicity of compounds, micellar electrokinetic chromatography (MEKC) is considered to be an appropriate one for bioactive molecules, as it closely mimics the physiological conditions. In this paper MEKC was used for the estimation of the lipophilicity of 24 derivatives of 8‐alkoxy‐7H‐purine‐2,6‐dione, designed and synthesized as potential antidepressant/anxiolytic and antipsychotic agents. The results of experimental method were compared with calculated in silico parameters (AlogPs and milogP by Virtual Computational Laboratory website, log PPallas by Pallas 3.1, Mlog P by Marvin, log PChemS by ChemSketch, log PChemDraw by ChemBioUltra) using Principal Component Analysis (PCA) method. Finally, using estimated log P values for selected compounds ligand – lipophilicity efficiency (LLE), per cent efficiency index (PEI), and binding efficiency index (BEI) parameters were calculated. Applied MEKC procedure could be used for selection of potential lead structure in a group of 7H‐purine‐2,6‐dione derivatives.

Phosphodiesterase 10 Inhibitors - Novel Perspectives for Psychiatric and Neurodegenerative Drug Discovery

BACKGROUND The phosphodiesterase 10 (PDE10) family, identified in 1999, is mainly expressed in the brain, particularly in the striatum, within the medium spiny neurons, nucleus accumbens, and olfactory tubercle. Inhibitors of PDE10 (PDE10-Is) are a conceptually rational subject for medicinal chemistry with potential use in the treatment of psychiatric and neurodegenerative diseases. OBJECTIVE This review is based on peer-reviewed published articles, and summarizes the cellular and molecular biology of PDE10 as a rational target for psychiatric and neurodegenerative drug discovery. Here, we present the classification of PDE10-Is from a medicinal chemistry point of view across a wide range of different, drug-like chemotypes starting from theophylline and caffeine analogs, papaverine and dimethoxy catechol type PDE10-Is, TP-10, MP-10, MP-10/papaverine/quinazoline series inhibitors, and ending with the newest inhibitors obtained from fragment-based lead discovery (FBLD). The authors have collated recent research on inhibition of PDE10A as a promising therapeutic strategy for psychiatric and neurodegenerative diseases, based on its efficacy in animal models of schizophrenia, Parkinsons, Huntingtons, and Alzheimers diseases. This review also presents pharmacological data on PDE10-Is as possible therapeutics for the treatment of cognitive deficits, obesity and depression. Moreover, it summarizes the current strategies for PDE10-Is drug discovery based on the results of clinical trials. The authors also present the latest studies on crystal structures of PDE10 complexes with novel inhibitors.