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This paper presents a computer-aided insight into the receptor-ligand interaction for novel analogs of the lead structure 5-(4-fluorophenyl)-3-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-5-methylimidazolidine-2,4-dione (1, MF-8), as part of the search for potent and selective serotonin 5-HT7 receptor (5-HT7R) agents. New hydantoin derivatives (4-19) were designed and synthesized. For 5-phenyl-3-(2-hydroxy-3-(4-(2-ethoxyphenyl)piperazin-1-yl)propyl)-5-methylimidazolidine-2,4-dione (4), its crystal structure was determined experimentally. Molecular modeling studies were performed, including both pharmacophore and structure-based approaches. New compounds were investigated in radioligand binding assays (RBA) for their affinity toward 5-HT7R and selectivity over 5-HT1AR, dopamine D2R and α1-, α2-and β-adrenoceptors. Selected compounds (5-8) were assessed for their antidepressant and anxiolytic effects in vivo in mice. Most of the tested compounds displayed potent affinity and selectivity for 5-HT7R in RBA, in particular seven compounds (4, 5, 7, 8 and 10-12, Ki ≤ 10 nM). Antidepressant-like activity in vivo for all tested compounds (5-8) was confirmed. SAR analysis based on both crystallography-supported molecular modeling and RBA results indicated that mono-phenyl substituents at both hydantoin and piperazine are more favorable for 5-HT7R affinity than the di-phenyl ones.

A number of cinnamamide derivatives possess anticonvulsant activity due to the presence of a number of important pharmacophore elements in their structures. In order to study the correlations between anticonvulsant activity and molecular structure, the crystal structures of three new cinnamamide derivatives with proven anticonvulsant activity were determined by X-ray diffraction, namely (R,S)-(2E)-N-(2-hydroxybutyl)-3-phenylprop-2-enamide–water (3/1), C13H17NO2·0.33H2O, (1), (2E)-N-(1-hydroxy-2-methylpropan-2-yl)-3-phenylprop-2-enamide, C13H17NO2, (2), and (R,S)-(2E)-N-(1-hydroxy-3-methyl-butan-2-yl)-3-phenylprop-2-enamide, C14H19NO2, (3). Compound (1) crystallizes in the space group P\overline{1} with three molecules in the asymmetric unit, whereas compounds (2) and (3) crystallize in the space group P21/c with one and two molecules, respectively, in their asymmetric units. The carbonyl group of (2) is engaged in an intramolecular hydrogen bond with the hydroxy group. This type of interaction is observed for the first time in these kinds of derivatives. A disorder of the substituent at the N atom occurs in the crystal structures of (2) and (3). The crystal packing of all three structures is dominated by a network of O—H...O and N—H...O hydrogen bonds, and leads to the formation of chains and/or rings. Furthermore, the crystal structures are stabilized by numerous C—H...O contacts. We analyzed the molecular structures and intermolecular interactions in order to propose a pharmacophore model for cinnamamide derivatives.

A series of 17 new phenoxyacetamides has been prepared via multistep chemical synthesis as a continuation of the research carried out by our group on di- and tri-substituted phenoxyalkyl and phenoxyacetyl derivatives of amines. The obtained compounds vary in an amide component, for example aminoalkanol or (un)modified amino acid moieties were introduced. The structures of selected products were confirmed by means of crystallographic methods. All 17 compounds were the subject of preliminary screening for potential anticonvulsant activity (MES, 6 Hz and/or scMET tests) and neurotoxicity (rotarod) in mice after intraperitoneal administration, while several active compounds were subsequently examined in additional models (e.g. MES and rotarod – rats, p.o. or i.p., hippocampal kindling – rats, i.p.). Finally, safety studies (cytotoxicity and cell proliferation assays on astrocytes, metabolic stability assessment, mutagenicity evaluation) were performed for several active compounds, including the most promising one (R-(–)-2-(2,6-dimethylphenoxy)-N-(1-hydroxypropan-2-yl)acetamide, MES ED(50) = 12.00 mg per kg b.w., rats, p.o.).

This paper presents a computer-aided insight into the receptor-ligand interaction for novel analogs of the lead structure 5-(4-fluorophenyl)-3-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-5-methylimidazolidine-2,4-dione (1, MF-8), as part of the search for potent and selective serotonin 5-HT

The paper discusses the issues connected with noninvasive thermal methods for the research and diagnosis of electromechanical objects. It covers the issues of thermovision and its application, as well as the most important techniques of thermovision measurements. Moreover, the paper presents the results of comparative analysis for several examined objects, i.e. commutator motor with heating spiral, alternating current commutator motor and asynchronous three-phase motor.

The paper presents studies concerning time analysis of data exchange in distributed control based on Ethernet wireless network model and relevant Modbus protocol. Presented control system operated in a real-time system that was responsible for continuous-time and periodic event processing. The events appeared at the input of system which had to generate answers (events) at the output. External event response time is closely conditioned by time which means that such systems have to ensure that response time is not exceeded, regardless of the sequence of object events. It is essential to keep the time determinism in the functioning of all real-time, regardless of whether it is a single PLC driver or their group of distributed control system.

The 2-amine derivatives of 5-arylidene-3H-imidazol-4(5H)-one are a new class of bacterial efflux pump inhibitors, the chemical compounds that are able to restore antibiotic efficacy against multidrug resistant bacteria. 5-Arylidene-3H-imidazol-4(5H)-ones with a piperazine ring at position 2 reverse the mechanisms of multidrug resistance (MDR) of the particularly dangerous Gram-negative bacteria E. coli by inhibition of the efflux pump AcrA/AcrB/TolC (a main multidrug resistance mechanism in Gram-negative bacteria, consisting of a membrane fusion protein, AcrA, a Resistant-Nodulation-Division protein, AcrB, and an outer membrane factor, TolC). In order to study the influence of the environment on the conformation of (Z)-5-(4-chlorobenzylidene)-2-[4-(2-hydroxyethyl)piperazin-1-yl]-3H-imidazol-4(5H)-one, (3), two different salts were prepared, namely with picolinic acid {systematic name: 4-[(Z)-4-(4-chlorobenzylidene)-5-oxo-3,4-dihydro-1H-imidazol-2-yl]-1-(2-hydroxyethyl)piperazin-1-ium pyridine-2-carboxylate, C16H20ClN4O2 +·C6H4NO2 −, (3 a )} and 4-nitrophenylacetic acid {systematic name: 4-[(Z)-4-(4-chlorobenzylidene)-5-oxo-3,4-dihydro-1H-imidazol-2-yl]-1-(2-hydroxyethyl)piperazin-1-ium 2-(4-nitrophenyl)acetate, C16H20ClN4O2 +·C8H6NO4 −, (3 b )}. The crystal structures of the new salts were determined by X-ray diffraction. In both crystal structures, the molecule of (3) is protonated at an N atom of the piperazine ring by proton transfer from the corresponding acid. The carboxylate group of picolinate engages in hydrogen bonds with three molecules of the cation of (3), whereas the carboxylate group of 4-nitrophenylacetate engages in hydrogen bonds with only two molecules of (3). As a consequence of these interactions, different orientations of the hydroxyethyl group of (3) are observed. The crystal structures are additionally stabilized by both C—H...N [in (3 a )] and C—H...O [in (3 a ) and (3 b )] intermolecular interactions. The geometry of the imidazolone fragment was compared with other crystal structures possessing this moiety. The tautomer observed in the crystal structures presented here, namely 3H-imidazol-4(5H)-one [systematic name: 1H-imidazol-5(4H)-one], is also that most frequently observed in other structures containing this heterocycle.

A series of twenty two (E)-N-cinnamoyl aminoalkanols derivatives monosubstituted in phenyl ring with 4-Cl, 4-CH3 or 2-CH3 was designed, synthesized and evaluated for anticonvulsant activity in rodent models of seizures: maximal electroshock (MES) test, subcutaneous pentylenetetrazole (scPTZ) test, and 6-Hz test. There were identified three most active compounds: S-(2E)-N-(1-hydroxypropan-2-yl)-3-(2-methylphenyl)prop-2-enamide (5) (ED50 MES = 42.56, ED50 scPTZ = 58.38, ED50 6-Hz 44 mA = 42.27 mg/kg tested in mice after intraperitoneal (i.p.) administration); R,S-(2E)-3-(4-chlorophenyl)-N-(1-hydroxybutan-2-yl)prop-2-enamide (6) (ED50 MES = 53.76, ED50 scPTZ = 90.31, ED50 6-Hz 44 mA = 92.86 mg/kg mice, i.p.); and R,S-(2E)-3-(4-chlorophenyl)-N-(2-hydroxypropyl)prop-2-enamide (11) (ED50 MES = 55.58, ED50 scPTZ = 102.15, ED50 6-Hz 44 mA = 51.27 mg/kg mice, i.p.). Their structures and configurations were confirmed by crystal X-ray diffraction method. The structure-activity studies among the tested series showed that chlorine atom in position para or methyl group in position ortho of phenyl ring were beneficial for anticonvulsant activity. Methyl group in position para of phenyl ring decreased anticonvulsant activity in reported series of cinnamamide derivatives.

A series of twenty two (E)-N-cinnamoyl aminoalkanols derivatives monosubstituted in phenyl ring with 4-Cl, 4-CH

A series of arylpiperazine derivatives of hydantoin-3-acetate, including previously obtained 5,5-diphenylhydantoin (1-7) and new-synthesized spirofluorene-hydantoin derivatives (8-12), were investigated in the search for new inhibitors of the tumour multidrug resistance (MDR) efflux pump P-glycoprotein (P-gp, ABCB1) overexpressed in mouse T-lymphoma cells. Synthesis of new compounds (8-12) was performed. Crystal structures of two compounds (8 and 11) were determined by X-ray diffraction method. The conformations of the investigated molecules (8 and 11) in the crystalline samples are different. The bent conformation seems to be more favourable for biological activity than the extended one. The efflux pump inhibitory properties of the compounds 1-12 were evaluated in the fluorescence uptake assay using rhodamine 123 dye in mouse T-lymphoma model in vitro. Their cytotoxic action was examined, too. All compounds with methyl acetate moiety displayed high potency to inhibit the MDR efflux pump. The most active compound, methyl 2-(1-(4-(4-(2,3-dichlorophenyl)piperazin-1-yl)butyl)-5,5-diphenylhydantoin-3-yl)acetate (5), tested at 1/10 of verapamil concentration displayed the 9-fold higher P-gp inhibitory action.

Epilepsy, one of the most frequent neurological disorders, is still insufficiently treated in about 30% of patients. As a consequence, identification of novel anticonvulsant agents is an important issue in medicinal chemistry. In the present article we report synthesis, physicochemical, and pharmacological evaluation of N-trans-cinnamoyl derivatives of R and S-2-aminopropan-1-ol, as well as R and S-2-aminobutan-1-ol. The structures were confirmed by spectroscopy and for derivatives of 2-aminopropan-1-ols the configuration was evaluated by means of crystallography. The investigated compounds were tested in rodent models of seizures: maximal electroshock (MES) and subcutaneous pentetrazol test (scPTZ), and also in a rodent model of epileptogenesis: pilocarpine-induced status prevention. Additionally, derivatives of 2-aminopropan-1-ols were tested in benzodiazepine-resistant electrographic status epilepticus rat model as well as in vitro for inhibition of isoenzymes of cytochrome P450. All of the tested compounds showed promising anticonvulsant activity in MES. For R(-)-(2E)-N-(1-hydroxypropan-2-yl)-3-phenylprop-2-enamide pharmacological parameters were found as follows: ED50 = 76.7 (68.2-81.3) mg/kg (MES, mice i.p., time = 0.5 h), ED50 = 127.2 (102.1-157.9) mg/kg (scPTZ, mice i.p., time = 0.25 h), TD50 = 208.3 (151.4-230.6) mg/kg (rotarod, mice i.p., time = 0.25 h). Evaluation in pilocarpine status prevention proved that all of the reported compounds reduced spontaneous seizure activity and act as antiepileptogenic agents. Both enantiomers of 2-aminopropan-1-ols did not influence cytochrome P450 isoenzymes activity in vitro and are likely not to interact with CYP substrates in vivo. Chirality 28:482-488, 2016. © 2016 Wiley Periodicals, Inc.

The rhodanine derivatives show various pharmacological activities. Rhodanine-3-carboxylic acids can be used as the substrates in various synthesis of compounds containing rhodanine-3-carboxyalkyl moiety. In this paper new crystal structures of rhodanine-3-acetic acid and its two homologues, i.e. rhodanine-3-propionic acid and rhodanine-3-butyric acid, are reported. The relationship between the length of the alkyl chain and the geometry of these molecules was studied. The crystal network is dominated by strong hydrogen bonds O–H···O formed by the carboxyl groups. Additionally, weak C–H···O and C–H···S contacts are observed. To study the difference in intermolecular interactions of rhodanine-3-carboxylic acid, three crystal structures were determined by X-ray diffraction method. The crystal network in all studied structures is built of homosynthons and stabilized by weak C–H···O and C–H···S contacts.

Correction for ‘Synthesis and anticonvulsant activity of phenoxyacetyl derivatives of amines, including aminoalkanols and amino acids’ by Katarzyna Pańczyk et al., MedChemComm, 2018, DOI: 10.1039/c8md00430g.

Adequate control of seizures remains an unmet need in epilepsy. In order to identify new anticonvulsant agents, a series of N-trans-cinnamoyl derivatives of selected aminoalkanols was synthetized. The compounds were obtained in the reaction of N-acylation carried out in a two-phase system. The substances were tested in animal models of seizures induced either electrically (maximal electroshock--MES; 6-Hz test) or chemically, by subcutaneous injection of pentetrazol (scPTZ). Neurotoxicity was determined by the rotarod test. Lipophilicity of the active compounds, expressed as RM0, was determined by reversed-phase thin layer chromatography and it ranged from 1.390 to 2.219. From among the tested series of compounds, R,S-(E)-N-(1-hydroxypropan-2-yl)-3-phenylprop-2-enamide (1) and R,S-(E)-N-(2-hydroxypropyl)-3-phenylprop-2-enamide (3) exhibited the best anticonvulsant activity. Compound 1, when administered to mice by intraperitoneal (i.p.) injection, showed the ED50 values of 86.6, 60.9, and 109.6 mg/kg in the MES, 6-Hz, and scPTZ tests, respectively. For compound 3, the ED50 values were found to be 47.1 mg/kg in MES and 77.1 mg/kg in scPTZ (mice, i.p.). The distances measured in crystals of compound 1 were: 7.99 A--from the phenyl ring to the hydroxyl group in the amide moiety, 5.729 A--from the phenyl ring to the amide group, and 3.112 A--from the amide group to the hydroxyl group in the amide moiety. The reported compounds did not exhibit mutagenic potential when assayed in the Ames test. Compounds 1 and 3 did not affect viability and morphology of human hepatocellular carcinoma cells (HepG2).

Deferiprone has a broad spectrum of biological effects. Thus it is interesting to investigate the influence of structural changes in deferiprone on its biological activity. This work presents a synthesis of a new selenium analogue of deferiprone, 3-hydroxy-1,2-dimethyl-4(1H)- pyridineselenone (3-HDPSe), and an improved method for synthesis of a sulfur analogue of deferiprone, 3-hydroxy-1,2-dimethyl-4(1H)-pyridinethione (3-HDPT). The structures of the synthesized compounds were confirmed by means of IR, MS, 1 H NMR and 13 C NMR measurements. Single crystals of the selenium analogue were obtained and the crystal structure determined using X-ray diffraction. Additionally DFT (the B3LYP functional combined with the 6-311++G** basis set) theoretical calculations were conducted and the results compared with experimental data.

Two homologues of epalrestat were synthesized and characterized by IR, MS, elemental analysis, 1H NMR, 13C NMR and their crystal structures were determined by X-ray diffraction method. The crystals of both compounds belong to the triclinic centrosymmetric space group. In both crystal structures the carboxyl groups are involved in the strong O–H···O hydrogen bonds. One compound crystallizes together with the dimethylformamide molecules from the solvent, forming with them intermolecular hydrogen bonds. In this crystal structure the disorder of solvent molecule is observed. The packing of the second compound is determined by hydrogen bonds between carboxyl groups leading to formation of characteristic molecular pairs. In addition, the crystal structures are also stabilized by weak contacts C–H···O and C–H···S. Both crystal structures were compared to that of the epalrestat determined earlier. The investigated compounds differ in planarity of molecules in comparison to epalrestat, but the same isomer and the extended conformation as in epalrestat molecule, are observed. To study the conformations and intermolecular interactions of potential inhibitors of aldose reductase two homologues of epalrestat were synthesized and their crystal structures were determined by single crystal X-ray diffraction method. The first homologue forms strong hydrogen bonds via carboxyl group with DMF from the solvent, whereas the second builds homosynthons by intermolecular interaction of two molecules via carboxyl groups.

Twenty four new N-[(dimethylphenoxy)alkyl]aminoalkanols have been synthesized and evaluated for anticonvulsant activity in a series of in vivo tests: the maximum electroshock (MES), 6 Hz, and subcutaneous metrazole (ScMet). The compounds were also evaluated for possible neurotoxicity in the rotarod test. The majority of the achieved compounds exhibit quantified anticonvulsant activity. The most active compound 4: R-(−)-2N-[(2,6-dimethylphenoxy)ethyl]aminopropan-1-ol is active in MES with ED50 = 5.34 (male mice, ip), 22.28 (female mice, ip), 51.19 (male mice, po), 7.43 (rats, ip), and 28.60 (rats, po). Thermal analysis proved that its hydrochloride (4a) can exist in polymorphic forms. The compound binds to σ, 5-HT1A, and α2 receptors as well as 5-HT transporter and it does not exhibit mutagenic properties.

The crystal structure of (3,5-diamino-6-chloro-pyrazine-2-carbonyl)-guanidine picrate has been determined with the use of X-ray diffraction method. The crystals are triclinic, space group PI with a = 10.2980(4) A, b = 12.4322(4) A, c = 14.4310(5) A, α = 66.317(2)∘, β = 70.077(2)∘, γ = 72.462(2)∘, Z = 2. The asymmetric unit consists of one amiloride cation, picrate anion, and three DMSO molecules from the solvent, two of which are disordered. The molecules of amiloride and picrate are almost planar. The guanidine group of amiloride is protonated and makes a kind of a salt bridge with phenolate and forms hydrogen bonds with ortho-nitro oxygen atoms of picrate. The pairs of amiloride cation–picrate anion, transformed by the inversion center and translated by 2 a and c, are mutually parallel and are connected by molecules of DMSO. The conformation of amiloride picrate is compared with those in other crystal structures.

International audience; In the search for new antimalarial drugs, design of hybrid molecules is recommended to improve biological activity and to decrease the risk of parasite resistance development. Ellagic acid, as an inhibitor of Plasmodium glutathione, presents an original mode of action and thus appears as a promising antiplasmodial compound. A new complex (AQ-EA) consisting of the well-known antimalarial drug, amodiaquine, and ellagic acid was obtained. The studied crystal structure of AQ-EA showed that the triclinic centrosymmetrical unit cell of the crystal contains two molecules of amodiaquine (AQ) and two symmetrically independent molecules of ellagic acid (EA). The packing of the molecules in the crystal is dominated by hydrogen bonds between AQ and EA. The antiplasmodial activity of the hybrid complex AQ-EA was also determined and compared with the values of IC50 for AQ and EA separately. Potentiation assays between both molecules were conducted to understand the pharmacological interactions between AQ and EA against Plasmodium falciparum in vitro. The hybrid complex AQ-EA (IC50 of 47nm) showed improved antiplasmodial activity in comparison with EA alone.

To study the solvatomorphism in ellagic acid two crystal structures have been determined with the use of X-ray diffraction method. The obtained single crystals of dimethyl sulfoxide solvate and of dimethylformamide solvate belong to $$ {P}\bar{1} $$ and to P21/c space groups, respectively. In both structures, the inversion centre is located in the centre of the molecule of ellagic acid, so the asymmetric units contain only half of this molecule and one molecule of the corresponding solvent. The packing of the ellagic acid molecules in the crystals of these two solvatomorphs is dominantly controlled by the molecules of solvents, which form different hydrogen bonding patterns. The molecules of ellagic acid are planar and connected by hydrogen bonds via molecules of solvent, giving the rise to chains throughout the crystal. This work has concentrated on the strong O–H···O hydrogen bonds and weak C–H···O interactions. To study the solvatomorphism in ellagic acid and its influence on intermolecular hydrogen bonding, two crystal structures have been determined using small molecule, single crystal with X-ray diffraction. Intermolecular hydrogen bonding for EA_DMSO show ring R 4 2 (14), whereas for EA_DMF, R 8 4 (36). Dashed lines indicate hydrogen bonds.

The X-ray structure analysis of a single crystal of 3-methyl-5-p-methylbenzylidene-2-selenohydantoin was carried out. The crystals are monoclinic, space group P2 1 /c, with a = 5.244(1) A, b = 19.402(2) A, c = 11.606(1) A, g = 94.64(1)°;, Z = 4. The molecule is a Z-isomer. The overall conformation is not exactly planar, the angle between the hydantoin and p-methylphenyl planes is 11.8(1)°;. The packing of the molecules in the unit cell can be described as an arrangement of molecular chains which interact with each other via weak-hydrogen bonds, C--H·;·;·;O. The chains consist of dimers in which molecules are linked together by two symmetry-equivalent hydrogen bonds, N--H·;·;·;Se, that form accros inversion centres. The dimers interact also via weak hydrogen bonds, C--H·;·;·;O, between methyl groups and carbonyls of molecules related by another inversion centres.