A stability indicating High Performance Liquid Chromatographic (HPLC) method was developed and validated for the estimation of combined tablet formulation of Amlodipine & Candesartan. Chromatographic separation was optimized by Binary Gradient System HPLC on a Grace C18 (250mm x 4.6ID, Particle size: 5 micron) utilizing a mobile phase consisting a methanol: phosphate buffer (pH-3, adjusted with 0.1% OPA) 80:20 % v/v at a flow rate of 0.8ml/min with UV-3000-M at 244nm. The retention time of Amlodipine & Candesartan was 4.2min and 6.3 min respectively.

Good linearity was obtained over the range of 5 μg/ml to 25 μg/ml & 8 μg/ml to 40 μg/ml for Amlodipine & Candesartan. Correlation coefficient was found to be 0.999 for both derivatives. The % RSD of precision Amlodipine & Candesartan was found to be 0.54 and 0.60 respectively. The % mean recovery was found to 98.93-99.00 % for Amlodipine and 99.75-99.87 %for Candesartan. The results obtained for accuracy, precision, LOD, LOQ and Ruggedness were within the limits. Thus the validated economical method was applied for forced degradation study of Amlodipine & Candesartan tablets.

A simple, accurate reversed-phase high-performance liquid chromatography method was developed and validated for simultaneous determination of gliclazide (GLZ) and fluoroquinolone antibacterial levofloxacin (LVO). The method was developed by using a stainless steel analytical column , C18 (250,4.6 mm,5µm). The system was operated using a mobile phase consisting of methanol and phosphate buffer (pH 3.0) at a flow rate of 0.8mL minˉ¹ with ultraviolet detection monitored at wavelength 228 nm. The above method was validated using ICH analytical method validation guidelines. Utilizing HPLC techniques, an assay was intended to determine in vitro effects of levofloxacin on sulphonyl urea an anti-diabetic gliclazide. Obtained results were further verified with UV spectrophotometric method. Availability of gliclazide was reduced in the presence of levofloxacin. This in vitro analyses confirms the co-administration of gliclazide and levofloxacin and may serve for designing further in vivo studies.

According to statistics, in 2012, there were estimated 1.4 million new colorectal cancer cases and 693,900 deaths. Breast cancer, the leading cause of cancer-related death among females worldwide, gave an estimated 1.7 million cases and 521,900 deaths in 2012. An estimated 527,600 cancer cases and 265,700 deaths in 2012 worldwide were caused by cervical cancer which is the third leading cause of cancer-related death in females [1].

Chemotherapeutics play an important role as anticancer agents, inducing apoptosis or restoring apoptotic functions of proteins. In view of the importance of sulfonamides and nitrogen containing heterocycles as privileged structures for designing anticancer agents, we decided to explore the synthesis and anticancer activity of molecular hybrids obtained by the combination of benzenesulfonamide and heterocycles such as imidazole, 1,2,4-triazole, benzimidazole and benzoxazole.

The anticancer activities of compounds were evaluated in vitro on MCF-7, HCT-116 and HeLa human tumor cell lines by MTT assay. The most active compounds bearing 3-methyl-2-thioxo-1H-imidazol-1-yl moiety exhibited selectivity against HeLa cells with IC₅₀ values 6‒7 µM. Meanwhile, 2-thioxo-1H-benzo[d]imidazole derivatives showed activity against HCT-116 cells in the range of IC₅₀: 17‒36 µM. The apoptotic potential of the most active compounds was analyzed through various assays in HeLa cells: phosphatidylserine translocation, cell cycle dystribution and caspase activation. Results indicated that compounds promoted cell cycle arrest at sub-G1 phase in cancer cells, induced caspase activity and increased the population of apoptotic cells.

[1] Torre L.A. et. al. Cancer Epidemiol. Biomarkers Prev. 25 (2016) 16‒27.

Although the resistance is commonly known as bacterial, this problem is not related only to the domain of bacteria. The occurrence of resistant mutants of fungi is also observed. Another problem with some known antifungal drugs is that only topical applications are used due to their toxicity or limited bioavailability [1]. Thus this situation justifies the urgency to design and discover not only antibacterial but also antifungal new drugs [2].

Styrylquinoline derivatives structurally related to dichloroquinoline (e.g. chloroxine) are potential antimicrobial compounds. These derivatives were studied by Cieslik et al. [3] recently. Some of these structures expressed antifungal activity comparable with or higher than the standard fluconazole. The antibacterial effect especially against Staphylococcus strains was observed as well [3]. Based on these results, new structures were synthesized and evaluated with respect to their activity, what is presented in this work. New compounds were tested against Candida strains for their antifungal effect and against Staphylococcus and Enteroccocus strains for their antibacterial activity. Antibacterial effects were tested also against methicillin-resistant staphylococci and vancomycin-resistant enterococci.

This contribution was supported by grant FaF UK/9/2018 of the Faculty of Pharmacy of the Comenius University, grant No. UK/229/2018 of the Comenius University, NCN grant Opus:DEC-2013/09/B/NZ7/00423 of the Polish National Centre for Science and partially by SANOFI-AVENTIS Pharma Slovakia, s.r.o.

1. Jampilek, J. Potential of agricultural fungicides for antifungal drug discovery. Expert Opin. Drug Dis. 2016, 11, 1-9.
2. Jampilek, J. How can we bolster the antifungal drug discovery pipeline? Future Med. Chem. 2016, 8, 1393-1397.
3. Cieslik, W.; Musiol, R.; Nycz, J.; Jampilek, J.; Vejsova, M.; Wolff, M.; Machura, B.; Polanski, J. Contribution to investigation of antimicrobial activity of styrylquinolines. Med. Chem. 2012, 20, 6960-6968.

Computational chemistry methods can significantly reduce experimental costs in early stages of a drug development project by filtering out unsuitable candidates and discovering new chemical matter. Molecular alignment is a key pre-requisite for 3D similarity evaluation between compounds and pharmacophore elucidation. Relying on the hypothesis that the variation in maximal achievable binding affinity for an optimized drug-like molecule is largely due to desolvation, we explore herein a novel small molecule 3D alignment strategy that exploits the partitioning of molecular hydrophobicity into atomic contributions in conjunction with information about the distribution of hydrogen-bond donor/acceptor groups in each compound. A brief description of the method, as implemented in the software package PharmScreen, is presented. The computational procedure is calibrated by using a dataset of 402 molecules pertaining to 14 distinct targets taken from the literature and validated against the CCDC AstraZeneca test set of 121 experimentally derived molecular overlays. The results confirm the suitability of MST based-hydrophobic parameters for generating molecular overlays with correct predictions obtained for 100%, 93%, and 55% of the molecules classified into easy, moderate and hard sets, respectively. The potential of this tool in a drug discovery campaign is then evaluated in a retrospective study with the aim to evaluate the correlations between activities and similarity score of a series of sigma-1 receptor ligands. The results confirm the suitability of the tool for Drug Discovery purposes finding the 67% of the most active ligands (≤10 nM) in Q1 of the ranking and the most active compound in position five.

Fatty acid amide hydrolase (FAAH) is a serine hydrolase that catalyzes the deactivating hydrolysis of the fatty acid ethanolamide family of signaling lipids, which includes anandamide (AEA), an endogenous ligand for cannabinoid receptors. Endogenous FAAH substrates such as AEA serve key regulatory functions in the body and have been implicated in a variety of pathological conditions including pain, inflammation, sleep disorders, anxiety, depression, and vascular hypertension, and there has been an increasing interest in the development of inhibitors of this enzyme.
Different structural classes of FAAH inhibitors have been reported including alpha-ketoheterocycles, (thio)hydantoins, piperidine/piperazine ureas, and carbamate derivatives. When tested, these compounds have been shown to be efficacious in models of inflammatory, visceral, and in some cases
neuropathic pain without producing the central effects seen with directly acting cannabinoid receptor agonists. An intriguing aspect of FAAH inhibition is that some currently marketed nonsteroidal anti-inflammatory drugs (NSAIDs) have also been shown to be weak inhibitors of FAAH, but can be used as a template for the design of more potent compounds. However, structure–activity relationships of analogues of clinically used NSAIDs with respect to FAAH inhibition have been examined scarcely in the literature. These findings led us to design and synthesis of new series of FAAH inhibitors derivable from conjugation of heterocyclic structures with NSAIDs as profens, fenamates, and new their correlate molecules. In this keynote we report on the synthetic pathways to transform old analgesic drugs into FAAH inhibitors and SAR studies on the new inhibitor series.

In continuation of a previous quantitative structure-activity relationship (QSAR) study on the antitrypanosomal activity of 69 sesquiterpene lactones (STLs) towards Trypanosoma brucei rhodesiense (Tbr) [1], the causative agent of East African form of human African trypanosomiasis, a QSAR model for a much larger and more diverse set of almost twice as many (130) of such natural products was established in this study. The extended data set has been obtained through a variety of STLs isolated and tested for antitrypanosomal activity within our group and further enhanced by 12 compounds obtained from literature, which have been tested in the same laboratory under identical conditions. Detailed QSAR analyses using various complementary approaches: (1) “Classical” descriptor-based QSAR using a genetic algorithm to select the most relevant variables, i.e. the same approach as in our previous study [1], (2) indicator variables deduced from pharmacophore features obtained from a 3D alignment of the most active molecules as applied in [2] and (3) hologram QSAR (HQSAR) based on molecular fingerprints of fragments extracted from the 2D molecular structure as used, e.g., in [3], have yielded models with good internal and external predictive ability. For a set of compounds as chemically diverse as the one under study, the models exhibited good coefficients of determination (R²) ranging from 0.71 to 0.85, as well as internal (leave-one-out Q² values ranging from 0.62 to 0.72) and external validation coefficients (P² values ranging from 0.54 to 0.73). The contributions of the various tested descriptors to the generated models are in good agreement with the results of previous QSAR studies and corroborate the fact that the antitrypanosomal activity of STLs is very much dependent on the presence and relative position of conjugated carbonyl groups within the molecular structure, but influenced by their hydrophilic/hydrophobic property and molecular shape

References

1. Schmidt, T. J. et al. Antimicrob. Agents Chemother. 2014, 58 (1), 325–332.
2. Schomburg, C. et al. Eur. J. Med. Chem. 2013, 63, 313–320.
3. Trossini, G. H. G. et al. Molecules 2014, 19 (7), 10546–10562.

MiR10b, miR335, miR21 are a class of microRNAs that are overexpressed in breast cancer. These microRNAs are significantly correlated to stage of metastasis. Thus, in our study we aimed to test the hypothesis that miRNAs have direct interactions with proteins and that they are able to inhibit/active the functional site of proteins and enzymes.

For that, we have chosen this 3 miRNAs related to breast cancer and studied interactions with some proteins associated with this cancer (onco-protein and suppressor proteins) included the BRCA1, BRCA2, palb2.., by processing the Docking and matching tools using especially Hex8 and HADDOCK sever. Mathematically, The Hidden Markov models were realized using Matlab script according the algorithm of Harrison et al.in order to study and validate the interactions and bonds among the protein and miRNAs.

The main results demonstrated the ability of miR10, miR335 and miR21 to create direct linkages with 3D protein structures. Furthermore, these interactions with viro-oncogenic and oncogenic proteins were observed at the RNA-Protein docking level.

These direct interactions allowed us to conclude that the influence levels of microRNAs are marked not only at the genomic level but can reach proteomic levels. Such direct interactions between the microRNAs and proteins can influence the direct regulation of the mechanisms of action in the biological systems. The strength of the interactions between the crystallized structures and the microRNAs is very large compared to those observed with the same crystal structures and the DNA fragments obtained during the crystallization, essentially those located at the promoter regions.

Protein EVI2A (Ecotropic viral integration site 2A) is a type 1 single pass membrane protein containing 236 amino acid residues. EVI2A is associated with several human diseases such as schizophrenia and numerous malignancies including breast and ovarian cancers.

Protein 3D structure helps in understanding the molecular function of the proteins and their important role in the biological scenario if any. Till date no 3D structure of protein EVI2A has been reported in public or private databases. To fill that gap, we evaluated some computational models including comparative methods, de novo approach, ab initio and threading based methods. The multiple models, including 3D model from I-Tasser, afforded a good agreement of output and structural features. A complete model of protein EVI2A was validated by ProSa and Ramachandran analyses. Molecular dynamics (MD) simulations were performed and analyzed using the GROMACS package and active site prediction was carried out using CASTp. The predicted model could be a starting point for structural biologists, drug discovery groups, and scientific community to further enhance their studies.

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Nowadays, a significant number of antiepileptic drugs aimed at influencing the main inhibitory transmitter – gamma-aminobutyric acid (GABA). Compounds with various chemical structures, binding to different GABA_A sites, potentiate the action of amino acid. Recent studies have reported that phenolic compounds such as vanillin and its derivatives also have actions within the CNS and act as enhancer of GABA potential. On the other hand, vanillin affects the peripheral nervous system as agonist of TRPV1 channels that are involved in the transmission and modulation of pain (nociception) as well as the integration of diverse painful stimuli. At the present study, the influence of vanillin and its derivatives (vanillin oxime, vanillyl alcohol and vanillic acid) on the central and peripheral nervous system was reliably confirmed by evaluating their anticonvulsant, antidepressant and analgesic activity. The present findings indicate that all aforementioned compounds possess antiseizure action after oral administration on PTZ-induced convulsion model. Antidepressant activity, studied by forced swimming test (FST), has been more pronounced manifested for vanillin and vanillic acid during 24 hours after administration. Intriguingly, TRPV1 agonist vanillin and its oxime after transdermal delivery produced hyperalgesia when tested on allylisothiocyanate- and capsaicin-induced models, whereas vanillyl alcohol and vanillic acid were found to reduce the pain sensation.