Lipophilicity Parameters Research Articles

Fluorinated nucleosides as an important class of anticancer and antiviral agents.

Fluorine-containing nucleoside analogs (NAs) represent a significant class of the US FDA-approved chemotherapeutics widely used in the clinic. The incorporation of fluorine into drug-like agents modulates lipophilic, electronic and steric parameters, thus influencing pharmacodynamic and pharmacokinetic properties of drugs. Fluorine can block oxidative metabolism of drugs and the formation of undesired metabolites by changing H-bonding interactions. In this review, we focus our attention on chemical fluorination reagents and methods used in the NAs field, including positron emission tomography radiochemistry. We briefly discuss both the cellular biology and clinical properties of FDA-approved and fluorine-containing nucleoside/nucleotide analogs in development as well as common resistance mechanisms associated with their use. Finally, we emphasize pronucleotide strategies used to improve therapeutic outcome of NAs in the clinic.

Divergent Synthesis of Cyclopropane-Containing Lead-Like Compounds, Fragments and Building Blocks through a Cobalt Catalyzed Cyclopropanation of Phenyl Vinyl Sulfide.

Cyclopropanes provide important design elements in medicinal chemistry and are widely present in drug compounds. Here we describe a strategy and extensive synthetic studies for the preparation of a diverse collection of cyclopropane‐containing lead‐like compounds, fragments and building blocks exploiting a single precursor. The bifunctional cyclopropane (E/Z)‐ethyl 2‐(phenylsulfanyl)‐cyclopropane‐1‐carboxylate was designed to allow derivatization through the ester and sulfide functionalities to topologically varied compounds designed to fit in desirable chemical space for drug discovery. A cobalt‐catalyzed cyclopropanation of phenyl vinyl sulfide affords these scaffolds on multigram scale. Divergent, orthogonal derivatization is achieved through hydrolysis, reduction, amidation and oxidation reactions as well as sulfoxide–magnesium exchange/functionalization. The cyclopropyl Grignard reagent formed from sulfoxide exchange is stable at 0 °C for > 2 h, which enables trapping with various electrophiles and Pd‐catalyzed Negishi cross‐coupling reactions. The library prepared, as well as a further virtual elaboration, is analyzed against parameters of lipophilicity (ALog P), MW and molecular shape by using the LLAMA (Lead‐Likeness and Molecular Analysis) software, to illustrate the success in generating lead‐like compounds and fragments.

Previously undescribed fridooleanenes and oxygenated labdanes from the brown seaweed Sargassum wightii and their protein tyrosine phosphatase-1B inhibitory activity

Previously undescribed fridooleanene triterpenoids 2α-hydroxy-(28,29)-frido-olean-12(13), 21(22)-dien-20-propyl-21-hex-4′(Z)-enoate, 2α-hydroxy-(28,29)-frido-olean-12(13), 21(22)-dien-20-prop-2(E)-en-21-butanoate and oxygenated labdane diterpenoids 2α-hydroxy-8(17), (12E), 14-labdatriene, 3β, 6β, 13α-tri hydroxy 8(17), 12E, 14-labdatriene were purified from the ethyl acetate-methanol and dichloromethane fractions of the air-dried thalli of Sargassum wightii (Sargassaceae), a brown seaweed collected from the Gulf-of-Mannar of Penninsular India. Inhibitory potential of Δ12 oleanenes towards protein tyrosine phosphatase-1B, the critical regulator of insulin-receptor activity were found to be significantly greater (IC50 0.1 × 10−2 and 0.09 × 10−2 mg/mL, respectively) than the standard sodium metavanadate (IC50 0.31 × 10−2 mg/mL). Fridooleanene triterpenoids displayed greater antioxidant activities (IC50DPPH 0.16–0.18 mg/mL) than the commercially available antioxidants, butylated hydroxytoluene and α-tocopherol (IC50DPPH 0.25 and 0.63 mg/mL, respectively). In general, the oxygenated labdane diterpenoids displayed significantly lesser antioxidant and tyrosine phosphatase-1B inhibitory properties than those exhibited by the fridooleanenes. Bioactivities of the titled compounds were primarily determined by the electronic and lipophilic parameters and not by the steric descriptors. Molecular docking simulations and kinetic studies were employed to describe the tyrosine phosphatase-1B inhibitory mechanism. The previously undescribed fridooleanene triterpenoids might be used as potential anti-hyperglycaemic pharmacophore leads to reduce the risk of elevated postprandial glucose levels.

Enhanced Antibacterial Activity of Ent-Labdane Derivatives of Salvic Acid (7α-Hydroxy-8(17)-ent-Labden-15-Oic Acid): Effect of Lipophilicity and the Hydrogen Bonding Role in Bacterial Membrane Interaction.

In the present study, the antibacterial activity of several ent-labdane derivatives of salvic acid (7α-hydroxy-8(17)-ent-labden-15-oic acid) was evaluated in vitro against the Gram-negative bacterium Escherichia coli and the Gram-positive bacteria Staphylococcus aureus and Bacillus cereus. For all of the compounds, the antibacterial activity was expressed as the minimum inhibitory concentration (MIC) in liquid media and minimum inhibitory amount (MIA) in solid media. Structure activity relationships (SAR) were employed to correlate the effect of the calculated lipophilicity parameters (logPow) on the inhibitory activity. Employing a phospholipidic bilayer (POPG) as a bacterial membrane model, ent-labdane-membrane interactions were simulated utilizing docking studies. The results indicate that (i) the presence of a carboxylic acid in the C-15 position, which acted as a hydrogen-bond donor (HBD), was essential for the antibacterial activity of the ent-labdanes; (ii) an increase in the length of the acylated chain at the C-7 position improved the antibacterial activity until an optimum length of five carbon atoms was reached; (iii) an increase in the length of the acylated chain by more than five carbon atoms resulted in a dramatic decrease in activity, which completely disappeared in acyl chains of more than nine carbon atoms; and (iv) the structural factors described above, including one HBD at C-15 and a hexanoyloxi moiety at C-7, had a good fit to a specific lipophilic range and antibacterial activity. The lipophilicity parameter has a predictive characteristic feature on the antibacterial activity of this class of compounds, to be considered in the design of new biologically active molecules.

Investıgatıon on quantıtatıve structure-actıvıty relatıonshıps of benzoylamıno benzoıc acıd derıvatıves as β-ketoacyl-acyl carrıer proteın synthase ııı (fabh) ınhıbıtors

Fatty acid biosynthesis is an important process in the microorganism life cycle. β-Ketoacyl-acyl Carrier Protein Synthase III (FABH) catalyzes a critical step in fatty acid biosynthesis via type ii fatty acid biosynthesis. Series of 43 Benzoyl amino benzoic acid derivatives were subjected to 2D and 3D quantitative structure-activity relationships (QSAR) analysis via multiple linear regression and partial least square analysis respectively. Statistically significant four QSAR models were developed with good cross-validated correlation coefficient and external validation values. Developed QSAR model indicated the significance of the lipophilic parameters in an inhibitory potential of benzoyl amino benzoic acid derivatives.

Chromatographic and Computational Assessment of Lipophilicity of New Anticancer Acetylenequinoline Derivatives.

The lipophilicity of a series of anticancer propargylquinoline derivatives is investigated using both chromatographic and computational methods. The parameters of the tested compounds' relative lipophilicity (logkw) are determined experimentally by the high-performance liquid chromatographic method (RP-HPLC, Accucore C18 column), using mixtures of acetonitrile and water as mobile phases. Mobile phase acetonitrile concentrations range between 50 and 80%. The logk values of the investigated compounds are linearly dependent upon the acetonitrile concentration. The analysis led to the calculation of the logkw parameter values for each of the tested compounds. The parameter logkw is discussed in terms of the relationship between structure and lipophilicity and consequently, transformed into the parameter logPHPLC using the calibration curve. The partition coefficients of the tested compounds (logPcalc) are also calculated by selected computer programs. A regression analysis and the sum of ranking differences are used to compare the lipophilic parameters of 15 acetylenequinoline derivatives, which were experimentally obtained (logPHPLC) and calculated using different mathematical methods (logPcalc). The 13C NMR spectra are used to examine the electronic relationships between properties and lipophilicity for the studied compounds. A regression study conducted on 15 compounds exhibits a linear correlation between lipophilicity and electronic properties, expressed as the 13C NMR chemical shift (R2 = 0.98).

Molecular, cellular and pharmacological effects of platinum(II) diiodido complexes containing 9-deazahypoxanthine derivatives: A group of broad-spectrum anticancer active agents

The platinum(II) iodido complexes 1–5 of the general formula cis-[PtI2(Ln)2], where Ln stands for O-substituted 9-deazahypoxanthine derivatives, were prepared and thoroughly characterized by various techniques, including multinuclear 1D and 2D NMR spectroscopy. The complexes were screened for their anticancer potential in vitro on ten human cancer cell lines, concretely breast adenocarcinoma (MCF7), osteosarcoma (HOS), lung carcinoma (A549), cervix epithelioid carcinoma (HeLa), malignant melanoma (G-361), prostate carcinoma (22Rv1, PC-3), hepatocellular carcinoma (HepG2), ovarian carcinoma (A2780) and cisplatin-resistant ovarian carcinoma (A2780R). The complexes exhibited significant wide-spectrum anticancer activity in vitro against all the employed cell lines, with IC50≈0.5–24.0μM. Very good correlation between the lipophilicity parameter log P and IC50 values of anticancer activity in vitro were obtained by simple QSAR analysis. The most lipophilic complexes 2, 4 and 5 showed the best results, as they reached the sub-micromolar IC50 values against the A2780 and A2780R sub-lines, with the best result equal 0.5±0.1μM on A2780 for complex 5. The in vivo testing of the representative complexes 1, 4 and 5 (applied at the same dose of Pt as 2mg/kg dose of cisplatin) on a L1210 leukaemia model revealed their positive effect on the prolongation of the mean survival time, even if it was lower than that of cisplatin. The 1H NMR interaction study revealed the ability of complexes to interact with glutathione (GSH) and 5′-guanosine monophosphate (GMP) and overall higher stability of the complexes 1–5 as compared to cisplatin. The electrospray-ionization mass spectrometry experiments with complex 1 identified the formation of a rich collection of hydrolytic species in water-containing media after 24h and the interaction intermediates with sulfur-containing biomolecule l-cysteine, but not with the reduced glutathione at physiologically relevant concentration levels.

Molecular Dynamics as a tool for in silico screening of skin permeability

Prediction of skin permeability can have manifold applications ranging from drug delivery to toxicity prediction. Along with the semi-empirical or mechanistic models proposed in the last decades, Molecular Dynamics simulations have recently become a fruitful tool for investigating membrane permeability, in particular as they allow the involved mechanisms to be modelled at a molecular level. Despite their significant structural complexity, Molecular Dynamics simulations can also be utilized to study permeation through the lipid matrix that characterizes the stratum corneum. In this work, Steered Molecular Dynamics simulations are performed on a suitably developed stratum corneum lipid matrix model. Regardless of their actual tortuous path within the stratum corneum, the permeants, taken from a Fully Validated dataset of 80 compounds of known permeability coefficient, are moved through the bilayer along its normal. This allows the exploration of all the possible conformational and physicochemical constraints the molecule experiences when moving through the bilayer. The so performed Steered Molecular Dynamics simulations are then utilized to extract the corresponding lipophilicity and diffusion parameters as computed by subdividing the entire path in 18 regions of different polarity and composition. Correlative analyses showed that the water-lipids interface is the best performing region and that significant enhancements can be gained by including parameters accounting for the temperature effect. Taken together, the developed models possess an enhanced predictive power compared to the existing equations and statistics are approaching the best possible results, given the uncertainty in the utilized permeability data.

A new model to determine lipophilicity of 1,2-ethanediamine-N,N'-di-2-(3-cyclohexyl)propanoic acid and 1,3-propanediamine-N,N'-di-2-(3-cyclohexyl)propanoic acid derivatives with antiproliferative activity by combining shake flask procedure and UHPLC-MS method.

Fourteen compounds representing ester derivatives of (S,S)-1,2-ethanediamine-N,N'-di-2-(3-cyclohexyl) propanoic and (S,S)-1,3-propanediamine-N,N'-di-2-(3-cyclohexyl)propanoic acids, expressing antiproliferative activity in vitro were examined. The objective of this study was to determinate their lipophilicity data, and also to ensure a mathematical model for prediction lipophilicity data of potential in vivo metabolites and new derivatives of (S,S)-1,2-ethanediamine-N,N'-di-2-(3-cyclohexyl)propanoic acid, based on chromatographic parameters. Experimentally, lipophilicity data were obtained by a traditional shake flask procedure and an ultra-high performance liquid chromatographic tandem mass spectrometry (UHPLC-MS) method. A correlation between the partition coefficient n-octanol/water (logD7,4) and chromatographic data (CHI, 0), and also, between logD7,4 and retention time was investigated. A very good correlation (r2=0.8969) was found between lipophilicity parameters 0 and logD7,4 obtained using UHPLC-MS and shake flask methods: logD7,4 = (0.11±0.01)×0 + (1.25±0.20)×Nc - (9.19±1.18); statistical parameter F=47.84; significance of F = 3.74×10-6, Nc=number of C atoms between two amino groups (Nc=2 for 1,2-ethanediamine derivatives and Nc=3 for 1,3-propanediamine derivatives). The model predictivity power was determined by cross validation leave one out (LOO) technique, and expressed by the term Q2, was 0.89. The developed model has good predictivity power for prediction lipophilicity data of potential in vivo metabolites of the investigated compounds, such as novel 1,2-ethanediamine and 1,3-propanediamine N,N'-di-2-(3-cyclohexyl)propanoic acid derivatives. Also, the lipophilicity data obtained in the present study correlated with the antiproliferative activity of the investigated substances shown previously in in vitro studies.

Application of thin-layer chromatography to evaluate the lipophilicity of 5,8-quinolinedione compounds

Lipophilicity is a very important property while designing new drugs. Its influence on the pharmacological responses of compounds has been known since the 19th century. Also, many researchers try to find the relationships between structure and activity of newly synthetized compounds. The aim of this study was to determine the lipophilicity of 5,8-quinolinedione derivatives using thin-layer chromatography. Moreover, the structure—activity correlation between experimental and theoretical parameters of lipophilicity and anticancer activity was described. A series of 18 compounds was investigated. Experimental lipophilicity was determined by use of reversed-phase thin-layer chromatography (RP-TLC) using RP-18 F254s plates impregnated with silicone oil and the mixture of acetone and water solution of buffer Tris (pH = 7.4) in different volume compositions as mobile phases. Values of calculated lipophilicity (ALOGPs, AClogP, miLogP, KOWWIN, XLOGP2, MLogP, ABlogP, and ACD/LogP) were taken from the internet datab...

Effect of charge of quaternary ammonium cations on lipophilicity and electroanalytical parameters: Task for ion transfer voltammetry

The electrochemical behavior of three differently charged drug molecules (zwitter-ionic acetylcarnitine, bi-cationic succinylcholine and tri-cationic gallamine) was studied at the interface between two immiscible electrolyte solutions. Tetramethylammonium was used as a model mono cationic molecule and internal reference. The charge and molecular structure were found to play an important role in the drug lipophilicity. The studied drugs gave a linear correlation between the water – octanol (logPoctanol) partition coefficients and the electrochemically measured water – 1,2-dichloroethane (logPDCE) partition coefficients. Comparison with tetraalkylammonium cations indicating that the correlation between logPoctanol and logPDCE is molecular structure dependent. The highest measured sensitivity and lowest limit of detection were found to be 0.543mA·dm3·mol−1 and 6.25μM, respectively, for the tri-cationic gallamine. The sensitivity for all studied ions was found to be a linear function of molecular charge. The dissociation constant of the carboxylic group of zwiter-ionic acetylcarnitine was calculated based on voltammetric parameters and was found to be 4.3. This study demonstrates that electrochemistry at the liquid – liquid interface is powerful technique when it comes to electroanalytical or pharmacokinetic drug assessment.

Lipophilicity estimation of statins as a decisive physicochemical parameter for their hepato-selectivity using reversed-phase thin layer chromatography

Lipophilicity plays a crucial role in determining the hepato-selectivity and hence, the biological activity and the associated side effects of statins. Herein, the employment of RP-TLC for estimation of lipophilicity of six statins namely; atorvastatin, simvastatin, pravastatin, lovastatin, rosuvastatin and fluvastatin is examined. A very good correlation between the chromatographically-determined retention parameters (relative lipophilicity (RM0) or lipophilic parameter (C0)) and both experimental and computed log P values were obtained. However, the results indicate that the type of organic modifier in the mobile phase system (methanol, acetonitrile and acetone) has a small influence on RM0 or C0 values. Higher values of RM0 or C0 are ascribed to lipophilic statins and lower values of RM0 or C0 are attributed to hydrophilic ones. Therefore, RM0 or C0 could be effectively used as simple practical predictors of extra-hepatic distributions of statins and thus their expected side effects. Furthermore, three QSPR (quantitative structure-property relationship) models were constructed to describe the relationship between RM0 with log P and log D of the statins under investigation. These models can be very useful to predict the lipophilicity of other members of statin drugs and might be expanded to newly synthesized compounds with the same structural features.

Comparative pharmacodynamic analysis of imidazoline compounds using rat model of ocular mydriasis with a test of quantitative structure–activity relationships

Imidazol(in)e derivatives, having the chemical structure similar to clonidine, exert diverse pharmacological activities connected with their interactions with alpha2-adrenergic receptors, e.g. hypotension, bradycardia, sedation as well as antinociceptive, anxiolytic, antiarrhythmic, muscle relaxant and mydriatic effects. The mechanism of pupillary dilation observed after systemic administration of imidazol(in)es to rats, mice and cats depends on the stimulation of postsynaptic alpha2-adrenoceptors within the brain. It was proved that the central nervous system (CNS)-localized I1-imidazoline receptors are not engaged in those effects. It appeared interesting to analyze the CNS-mediated pharmacodynamics of imidazole(in)e agents in terms of their chromatographic and calculation chemistry-derived parameters.In the present study a systematic determination and comparative pharmacometric analysis of mydriatic effects in rats were performed on a series of 20 imidazol(in)e agents, composed of the well-known drugs and of the substances used in experimental pharmacology. The eye pupil dilatory activities of the compounds were assessed in anesthetized Wistar rats according to the established Koss method. Among twenty imidazol(in)e derivatives studied, 18 produced diverse dose-dependent mydriatic effects. In the quantitative structure–activity relationships (QSAR) analysis, the pharmacological data (half maximum mydriatic effect – ED50 in μmol/kg) were considered along with the structural parameters of the agents from molecular modeling. The theoretically calculated lipophilicity parameters, CLOGP, of imidazol(in)es, as well as their lipophilicity parameters from HPLC, logkw, were also considered. The attempts to derive statistically significant QSAR equations for a full series of the agents under study were unsuccessful. However, for a subgroup of eight apparently structurally related imidazol(in)es a significant relationship between log(1/ED50) and logkw values was obtained. The lack of “predictive” QSAR for the whole series of the structurally diverse agents is probably due to a complex mechanism of the ligand–alpha2-adrenergic receptor interactions, which are predominantly of a highly structurally specific polar nature. Such interactions are difficult to quantify with the established chemical structural descriptors, contrary to the less specific, molecular bulkiness-related interactions.

Multi-Target Mining of Alzheimer Disease Proteome with Hansch's QSBR-Perturbation Theory and Experimental-Theoretic Study of New Thiophene Isosters of Rasagiline.

Hansch's model is a classic approach to Quantitative Structure-Binding Relationships (QSBR) problems in Pharmacology and Medicinal Chemistry. Hansch QSAR equations are used as input parameters of electronic structure and lipophilicity. In this work, we perform a review on Hansch's analysis. We also developed a new type of PT-QSBR Hansch's model based on Perturbation Theory (PT) and QSBR approach for a large number of drugs reported in CheMBL. The targets are proteins expressed by the Hippocampus region of the brain of Alzheimer Disease (AD) patients. The model predicted correctly 49312 out of 53783 negative perturbations (Specificity = 91.7%) and 16197 out of 21245 positive perturbations (Sensitivity = 76.2%) in training series. The model also predicted correctly 49312/53783 (91.7%) and 16197/21245 (76.2%) negative or positive perturbations in external validation series. We applied our model in theoretical-experimental studies of organic synthesis, pharmacological assay, and prediction of unmeasured results for a series of compounds similar to Rasagiline (compound of reference) with potential neuroprotection effect.

Anti-inflammatory choline based ionic liquids: Insights into their lipophilicity, solubility and toxicity parameters

Abstract The impact on in vivo efficacy and safety of two novel ionic liquids based on the association of choline with non-steroidal anti-inflammatory drugs, ketoprofen and naproxen forming IL-APIs, was evaluated. Their lipophilicity, solubility and toxicity were assessed aiming the illustration of the pharmaceutical profile and potential toxic impact. Partition coefficient was determined using micelles of hexadecylphosphocholine and UV–Vis derivative spectroscopy. Additionally, solubility in phosphate buffer pH 7.4 was measured using a modified shake flask method and UV–Vis spectroscopy as detection technique. Ultimately, toxicity was considered resorting to a fully automated cytochrome c oxidase assay based on microfluidics. The obtained results demonstrated that the IL-APIs' drug format has the ability to interact with biological membranes and also improves solubility up to 58 times. Moreover, it was evidenced that, although being a nutrient, choline influences the IL-APIs' toxicity. The studied anti-inflammatory IL-APIs exhibited promising properties regarding their incorporation in pharmaceutical formulations.

Precise prediction of activators for the human constitutive androstane receptor using structure-based three-dimensional quantitative structure–activity relationship methods

The constitutive androstane receptor (CAR, NR1I3) regulates the expression of numerous drug-metabolizing enzymes and transporters. The upregulation of various enzymes, including CYP2B6, by CAR activators is a critical problem leading to clinically severe drug–drug interactions (DDIs). To date, however, few effective computational approaches for identifying CAR activators exist. In this study, we aimed to develop three-dimensional quantitative structure–activity relationship (3D-QSAR) models to predict the CAR activating potency of compounds emerging in the drug-discovery process. Models were constructed using comparative molecular field analysis (CoMFA) based on the molecular alignments of ligands binding to CAR, which were obtained from ensemble ligand-docking using 28 compounds as a training set. The CoMFA model, modified by adding a lipophilic parameter with calculated logD7.4 (S+logD7.4), demonstrated statistically good predictive ability (r2 = 0.99, q2 = 0.74). We also confirmed the excellent predictability of the 3D-QSAR model for CAR activation (r2pred = 0.71) using seven compounds as a test set for external validation. Collectively, our results indicate that the 3D-QSAR model developed in this study provides precise prediction of CAR activating potency and, thus, should be useful for selecting drug candidates with minimized DDI risk related to enzyme-induction in the early drug-discovery stage.

SYNTHESIS, CHARACTERIZATION, BIOLOGICAL EVALUATION AND DOCKING OF SOME NOVEL SUBSTITUTED 1, 3-THIAZINE DERIVATIVES

Objective: Chalcones and their heterocyclic analogs represent an important class of small molecules which have a wide range of pharmacological activities. Therefore, in this study, synthesis and anticonvulsant and antimicrobial activities of some new 1, 3-thiazines have been extensively discussed.Methods: The reaction mixture of 4-tert-butylcyclohexanone on Claisen-Schmidt condensation with various aromatic aldehydes in the presence of dilute sodium hydroxide afforded the corresponding chalcones. Further, these compounds were subjected to cocondensation with thiourea, in the presence of isopropanol, catalyzed by aqueous potassium hydroxide to form 4-aryl 8-arylidene-5, 6-dihydro-2-imino-6-methyl-4H, 7H-(1, 3) benzothiazines. The structures of the newly synthesized compounds have been established on the basis of their spectral analysis. The newly synthesized compounds have been tested for their biological screening. Antimicrobial activity by cup plate agar diffusion method and antiepileptic activity by pentylenetetrazole (PTZ) induced seizures model, using diphenyl hydantain as standard, and also they are subjected to molecular properties prediction, toxicity, drug-likeness, lipophilicity and solubility parameters determination were done by using Osiris program, Molsoft, Prototox and ALOGPS 2.1 software. The binding mode of the synthesized compounds with active protein site has been predicted using docking method.Results: Most of the compounds have shown good anticonvulsant as well as antimicrobial activities, but it is less than the standard drugs. 1, 3-thiazines derivatives were more potent, and among them, compounds TB5 andTB7 were the most active compounds in these series; TB5 whichcontains isopropyl phenyl moiety, was shown moderate potent activity with onset of convulsion at 14.1 min and TB7 containing 3, 4, 5-trimethoxyphenyl substituents on the thiazine moiety was more potent as it has prolonged the onset of convulsions by 18.7 min. Whereas in the case of antimicrobial activity of the compounds, from the results we have observed that TB5 have been shown greatest antimicrobial activity in all the bacterial and fungal strains, TB2 also shown superior activity, the others have been shown good antimicrobial activity.Conclusion: According to the activity studies, it is observed that the synthesis and antimicrobial as well as anticonvulsant activities of novel 1, 3-thiazine derivatives have been shown better activity. Moreover molecular docking results give an insight into how further modification of the lead compound can be carried out for higher inhibitory activity. In particular, compounds with electron withdrawing substituents along with lipophilic methoxyl and isopropyl groups were more potent.

Assessment of the chromatographic lipophilicity of eight cephalosporins on different stationary phases

The retention behaviors were investigated for a series of eight cephalosporins in thin-layer chromatography (TLC) using stationary phases of RP-2, RP-8, RP-18, NH2, DIOL, and CN chemically bonded silica gel. Additionally, various binary mobile phases (water/methanol and water/acetone) were used in different volume proportions. The retention behavior of the analyzed molecules was defined by RM0 constant. In addition, reversed phase high performance liquid chromatography (RP-HPLC) was performed in lipophilicity studies by using immobilized artificial membrane (IAM) stationary phase. Obtained chromatographic data (RM0 and logk'IAM) were correlated with the lipophilicity, expressed as values of the log calculated (logPcalc) and experimental (logPexp(shake-flask)) partition coefficient. Principal component analysis (PCA) was applied in order to obtain an overview of similarity or dissimilarity among the analyzed compounds. Hierarchical cluster analysis (HCA) was performed to compare the separation characteristics of the applied stationary phases. This study was undertaken to identify the best chromatographic system and chromatographic data processing method to enable the prediction of logP values. A comprehensive chromatographic investigation into the retention of the analyzed cephalosporins revealed a similar behavior on RP-18, RP-8 and CN stationary phases. The weak correlations obtained between experimental and certain computed lipophilicity indices revealed that RM0 and PC1/RM are relevant lipophilicity parameters and the RP-8, CN and RP-18 plates are appropriate stationary phases for lipophilicity investigation, whereas computational approaches still cannot fully replace experimentation.

Synthesis, structure confirmation, identification of in vitro antiproliferative activities and correlation of determined lipophilicity parameters with in silico bioactivity descriptors of two novel classes of fused azaisocytosine-like congeners

The goals of the present investigation were the development of two independent synthetic approaches, the original spectroscopic characterisation, the identification of in vitro antitumour activities and the correlation of determined retention factors with in silico pharmacokinetic descriptors of two novel classes of potential antimetabolites based on the privileged 7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4(6H)-one scaffold. Well-established, scalable and optimised synthetic approaches leading to two novel classes of the desired compounds (7–12 and 13–17) were developed. These original fused azaisocytosine-like congeners were screened in vitro with the purpose of identifying molecules with better biological profiles that are suitable for further more detailed drug development studies. All the synthesised compounds proved to be strongly antiproliferative active against human neoplastic cell lines (A549, HeLa, T47D and TOV112D) and revealed higher cytotoxic effects in A549, HeLa and T47D cells than the known antitumour agent – pemetrexed. Four potent fused azaisocytosine-like congeners (10, 12, 15 and 16) proved to be the most promising lead structures as they reveal the explicitly lower cytotoxicity for non-tumoural cells. These molecules could be employed for novel effective anticancer strategies directed towards designing more selective and safer cytotoxic agents. In addition, a number of compounds (that target epithelial cancer cells and inhibit their growth) have been preselected because they present optimum lipophilicity ranges significantly correlated with in silico bioactivity descriptors (such as %F, Caco-2, Pe,jejunum, logBB, fu,brain, logPHSA) important for the optimal pharmacokinetic profile in vivo.

Lipophilicity Study of 1-(Benzofuran-2-yl)ethan-1-one Oxime and its Substituted O-Benzyl Ethers

Heterocyclic oxime ethers play a significant role in organisms due to their biological activity. Lipophilicity is an important parameter that may affect biological activity of the compounds 1-(benzofuran-2-yl)ethan-1-one oxime and its nine biologically active ethers. The relationship between the structure and lipophilicity parameters (log kw values) of the ten compounds is here described. Reversed phase high performance liquid chromatography (RP-HPLC) method was used having methanol, 2-propanol and acetonitrile as organic modifiers of the mobile phases. Both experimental (log kw) and calculated (log P) parameters showed to be strongly positively correlated. The weakest correlation with all the data was for the log kw methanol. For all of analyzed compounds, log kw values are smaller than 5 (except for analyses carried out in methanol), and this result corresponds to the Lipinski’s rule in the range of lipophilicity. Therefore, in the case of their use as drugs, they will be probably active after oral application.