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The article discusses the effects of methylation in medicinal chemistry. It says that methylation can increase the lipophilicity and solubility of bioactive molecule through mechanisms like an increased hydrophobic interactions. It states that methyl groups have stereoelectronic effects in drug design and in the discovery of various drugs including cimetidine, lumiracoxib, and diazepam. Moreover, methyl groups play a role in accelerating the metabolism of bioactive compounds.

Describes the results of a study of the electron impact mass spectrometry behavior of a series of 3-[3-(4-aryl)-1,2,4-oxadiazole-5-yl] acyl arylaldehyde hydrazone derivatives. Fragmentation patterns; Agreement between the proposed structures and the relative abundance of the peaks molecular ion for all compounds containing bromine.

The 4-aminoquinazoline scaffold is a privileged structure in medicinal chemistry. Regioselective nucleophilic aromatic substitution (SNAr) for replacing the chlorine atom at the 4-position of 2,4-dichloroquinazoline precursors is well documented in the scientific literature and has proven useful in synthesizing 2-chloro-4-aminoquinazolines and/or 2,4-diaminoquinazolines for various therapeutic applications. While numerous reports describe reaction conditions involving different nucleophiles, solvents, temperatures, and reaction times, discussions on the regioselectivity of the SNAr step remain scarce. In this study, we combined DFT calculations with 2D-NMR analysis to characterize the structure and understand the electronic factors underlying the regioselective SNAr of 2,4-dichloroquinazolines for the synthesis of bioactive 4-aminoquinazolines. DFT calculations revealed that the carbon atom at the 4-position of 2,4-dichloroquinazoline has a higher LUMO coefficient, making it more susceptible to nucleophilic attack. This observation aligns with the calculated lower activation energy for nucleophilic attack at this position, supporting the regioselectivity of the reaction. To provide guidance for the structural confirmation of 4-amino-substituted product formation when multiple regioisomers are possible, we employed 2D-NMR methods to verify the 4-position substitution pattern in synthesized bioactive 2-chloro-4-aminoquinazolines. These findings are valuable for future research, as many synthetic reports assume regioselective outcomes without sufficient experimental verification. [ABSTRACT FROM AUTHOR]

Inappropriate expression of histone deacetylase (HDAC-6) and deregulation of the phosphatidylinositol 3-kinase (PI3K) signalling pathway are common aberrations observed in cancers. LASSBio-2208, has been previously described as a dual inhibitor in the nanomolar range of HDAC-6 and PI3Kα and is three times more potent in inhibiting HDAC-6. In this paper we described the cytotoxic and antiproliferative potency of LASSBio-2208 on different tumour cell lines, its possible synergism effect in association with PI3K and HDAC-6 inhibitors, and its drug metabolism and pharmacokinetics (DMPK) in vitro profile. Our studies have demonstrated that LASSBio-2208 has moderate cytotoxic potency on breast cancer cell line MCF-7 (IC50 = 23 µM), human leukaemia cell line CCRF-CEM (IC50 = 8.54 µM) and T lymphoblast cell line MOLT-4 (IC50 = 7.15 µM), with no cytotoxic effect on human peripheral blood mononuclear cells (hPBMC). In addition, it has a good antiproliferative effect on MCF-7 cells (IC50 = 5.44 µM), low absorption by parallel artificial membrane permeability—gastrointestinal tract (PAMPA—GIT) and low permeation by parallel artificial membrane permeability—blood–brain barrier (BBB) (PAMPA—BBB), exhibiting high metabolic stability in rat plasma. Moreover, LASSBio-2208 exhibited synergism when combined with getadolisib and tubastatin A, using the concentrations corresponding to their CC50 values on MOLT-4 and CCRF-CEM cells. [ABSTRACT FROM AUTHOR]

Objectives In this work, we further investigated the effect of the compound LASSBio-752 in thrombosis models in rats. Methods Arterial and venous thrombosis model, ex-vivo recalcification time and a PTT and PT. Key findings In the venous thrombosis model, oral administration of LASSBio-752 [48.2 mg (100 μmol)/kg] one hour before the thrombus induction decreased thrombus weight by 37 ± 0.2%. Interestingly, the antithrombotic action of this compound [48.2 mg (100 μmol)/kg] occurred at 87.5 ± 2.1% of inhibition after 24 h of administration and showed a lasting activity. When tested on the arterial thrombosis model, after a 1-h interval, there was already an increase in time to total occlusion of 34 ± 2.4 min, but the greatest effect was observed at intervals between 6 and 15 h of administration, when no occlusion of the artery was observed. The antithrombotic effect was reduced after 24 h when the occlusion time was 23.8 ± 2.3 min, close to that of the control, 17.6 ± 2.0 min. We also observed that bleeding was not excessive in any of the intervals tested. Conclusions Our results indicate that compound LASSBio-752 is a potential candidate for utilization in the treatment of thromboembolic diseases. [ABSTRACT FROM AUTHOR]

LASSBio-1920 was synthesized due to the poor solubility of its natural precursor, combretastatin A4 (CA4). The cytotoxic potential of the compound against human colorectal cancer cells (HCT-116) and non-small cell lung cancer cells (PC-9) was evaluated, yielding IC50 values of 0.06 and 0.07 μM, respectively. Its mechanism of action was analyzed by microscopy and flow cytometry, where LASSBio-1920 was found to induce apoptosis. Molecular docking simulations and the enzymatic inhibition study with wild-type (wt) EGFR indicated enzyme-substrate interactions similar to other tyrosine kinase inhibitors. We suggest that LASSBio-1920 is metabolized by O-demethylation and NADPH generation. LASSBio-1920 demonstrated excellent absorption in the gastrointestinal tract and high central nervous system (CNS) permeability. The pharmacokinetic parameters obtained by predictions indicated that the compound presents zero-order kinetics and, in a human module simulation, accumulates in the liver, heart, gut, and spleen. The pharmacokinetic parameters obtained will serve as the basis to initiate in vivo studies regarding LASSBio-1920's antitumor potential. [ABSTRACT FROM AUTHOR]

Esters are one of the major functional groups present in the structures of prodrugs and bioactive compounds. Their presence is often associated with hydrolytic lability. In this paper, we describe a comparative chemical and biological stability of homologous esters and isosteres in base media as well as in rat plasma and rat liver microsomes. Our results provided evidence for the hydrolytic structure lability relationship and demonstrated that the hydrolytic stability in plasma and liver microsome might depend on carboxylesterase activity. Molecular modelling studies were performed in order to understand the experimental data. Taken together, the data could be useful to design bioactive compounds or prodrugs based on the correct choice of the ester subunit, addressing compounds with higher or lower metabolic lability. [ABSTRACT FROM AUTHOR]

Combretastatin A-4 (CA-4, 1) is an antimicrotubule agent used as a prototype for the design of several synthetic analogues with anti-tubulin activity, such as LASSBio-1586 (2). A series of branched and unbranched homologs of the lead-compound 2, and vinyl, ethinyl and benzyl analogues, were designed and synthesized. A comparison between the cytotoxic effect of these homologs and 2 on different human tumor cell lines was performed from a cell viability study using MTT with 48 h and 72 h incubations. In general, the compounds were less potent than CA-4, showing CC50 values ranging from 0.030 μM to 7.53 μM (MTT at 72 h) and 0.096 μM to 8.768 μM (MTT at 48 h). The antimitotic effect of the target compounds was demonstrated by cell cycle analysis through flow cytometry, and the cellular mechanism of cytotoxicity was determined by immunofluorescence. While the benzyl homolog 10 (LASSBio-2070) was shown to be a microtubule stabilizer, the lead-compound 2 (LASSBio-1586) and the methylated homolog 3 (LASSBio-1735) had microtubule destabilizing behavior. Molecular docking studies were performed on tubulin protein to investigate their binding mode on colchicine and taxane domain. Surprisingly, the benzyl homolog 10 was able to modulate EGFR phosphorylate activity in a phenotypic model. These data suggest LASSBio-2070 (10) as a putative dual inhibitor of tubulin and EGFR. Its binding mode with EGFR was determined by molecular docking and may be useful in lead-optimization initiatives. [ABSTRACT FROM AUTHOR]

This review aims to highlight microwave-assisted organic synthesis as applied to medicinal chemistry in the last years, showing some reactions performed under microwave irradiation for the synthesis of distinct structurally molecules of biological interest, divided into the following groups: antineoplastics, anti-inflammatory, antimicrobial agents, antivirals, agents for the treatment of neglected diseases and central nervous system-acting prototypes. [ABSTRACT FROM AUTHOR]

Abstract: The search for bioactive conformations from prototypes is mostly referenced on crystallographic ligand–receptor complexes, in which the molecule conformation is already caged inside its binding site. However, the complexation process is a thermodynamic event depending on both complexed and uncomplexed states. As ligand affinity originates from such equilibrium, the development of novel computational models capable of supplying data on ligand dynamics in biological solutions is potentially applicable in more efficient methods for prediction of compounds binding and affinity. In this context, the current work employs a series of molecular dynamics simulations on three N-acylhydrazone derivatives, already shown to present promising cardioinotropic and vasodilatory activities, in order to obtain a precise characterization of each compound conformational ensemble in aqueous solutions, instead of a single minimum energy conformation. Consequently, we were able to observe the influence of each functional group of the studied molecules on the conformation of the entire compounds and thus on the exposure of functional groups that might potentially bind to target receptors. Additionally, the differences between the molecules conformational behavior were characterized, supporting a spatial and temporal image of each ligand, which may be potentially correlated to their biological activities. So in the context of conformational selection, such strategy may represent a useful methodology to contribute in the choice of ligands conformations for both 3D-QSAR and docking calculations. [Copyright &y& Elsevier]

In this study we describe a new comparative molecular field analysis (CoMFA) model of dihydroquinazolinone and tetrasubstituted imidazole compounds with p38 MAPK inhibitory activity. A series of 51 (a training set of 40 and a test set of 11) dihydroquinazolinone [Bioorg. Med. Chem. Lett. 2003, 13, 277.] and tetrasubstituted imidazole [J. Med. Chem. 1999, 42, 2180.] derivatives known as p38 mitogen-activated protein kinase (p38 MAPK) selective inhibitors was studied by quantitative structure–activity relationship (3D-QSAR) analysis using comparative molecular field analysis. The 3D-QSAR models were generated and evaluated by a scheme that combines a genetic algorithm (GA) optimization with partial least squares (PLS) regression and by crossvalidation using the leave-one-out technique. The model was able to efficiently predict the activities of the compounds of the test set, suggesting that it can be used for the planning of new p38 MAPK inhibitor candidates useful to treat chronic inflammatory states. [Copyright &y& Elsevier]

Herein, the LASSBio Chemical Library is presented as a valuable source of compounds for screening to identify hits suitable for subsequent hit-to-lead optimization stages. A feature of the LASSBio Chemical Library worth highlighting is the fact that it is a smart library designed by medicinal chemists with pharmacological activity as the main priority. The great majority of the compounds part of this library have shown in vivo activity in animal models, which is an indication that they possess overall favorable bioavailability properties and, hence, adequate pharmacokinetic profiles. This, in turn, is supported by the fact that approximately 85% of the compounds are compliant with Lipinski's rule of five and ca. 95% are compliant with Veber's rules, two important guidelines for oral bioavailability. In this work it is presented a virtual screening methodology combining a pharmacophore-based model and an empirical Gibbs free energy-based model for the ligand–protein interaction to explore the LASSBio Chemical Library as a source of new hits for the inhibition of the phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ) enzyme, which is related to the development of viral infections (including enteroviruses, SARS coronavirus, and hepatitis C virus), cancers and neurological diseases. The approach resulted in the identification of two hits, LASSBio-1799 (7) and LASSBio-1814 (10), which inhibited the target enzyme with IC50 values of 3.66 μM and IC50 and 6.09 μM, respectively. This study also enabled the determination of the structural requirements for interactions with the active site of PI4KIIIβ, demonstrating the importance of both acceptor and donor hydrogen bonding groups for forming interactions with binding site residues Val598 and Lys549. [ABSTRACT FROM AUTHOR]

Breast cancer is the leading cause of cancer death among women worldwide. About 75% of all diagnosed cases are hormone-positive, which are treated with hormone therapy. However, many patients are refractory or become resistant to the drugs used in therapeutic protocols. In this scenario, it is essential to identify new substances with pharmacological potential against breast cancer. VEGFR2 inhibitors are considered promising antitumor agents not only due to their antiangiogenic activity but also by inhibiting the proliferation of tumor cells. Thus, the present study aimed to evaluate the effects of N -acylhydrazone derivative LASSBio-2029 on the proliferative behavior of MCF-7 cells. We observed a promising antitumor potential of this substance due to its ability to modulate critical cell cycle regulators including mitotic kinases (CDK1 , AURKA, AURKB , and PLK1) and CDK inhibitor (CDKN1A). Increased frequencies of abnormal mitosis and apoptotic cells were observed in response to treatment. A molecular docking analysis predicts that LASSBio-2029 could bind to the proto-oncoprotein ABL1, which participates in cell cycle control, interacting with other controller proteins and regulating centrosome-associated tubulins. Finally, we created a gene signature with the downregulated genes, whose reduced expression is associated with a higher relapse-free survival probability in breast cancer patients. • N -acylhydrazones derivatives are cytotoxic to MCF-7 breast cancer cells. • The N-acylhydrazone derivative LASSBio-2029 induces apoptosis in MCF-7 cells. • LASSBio-2029 modulates mitotic kinases and disturbs mitotic events in MCF-7 cells. • LASSBio-2029 downregulates the mitotic genes CNNB1 , CDK1 , AURKA , AURKB , and PLK1. • Downregulated genes are associated with a higher survival in breast cancer patients. [ABSTRACT FROM AUTHOR]

Abstract Immunosuppressive drugs are widely used for the treatment of immune-mediated diseases and inflammation, but the toxicity and side effects of the available immunosuppressors make the search of new agents of great relevance. Here, we evaluated the immunomodulatory activity of an N- acylhydrazone derivative, (E)- N ′-(3,4-dimethoxybenzylidene)-4-methoxybenzohydrazide (LASSBio-1386), a phosphodiesterase-4 (PDE-4) inhibitor. LASSBio-1386 inhibited lymphocyte activation in a concentration-dependent fashion, decreasing lymphoproliferation and IFN-γ and IL-2 production stimulated by anti-CD3/CD28 mAbs or concanavalin A (Con A) and inducing cell-cycle arrest in the G0/G1 phase. These effects were not blocked by RU486, a glucocorticoid receptor (GR) antagonist, indicating an effect independent of glucocorticoid receptor activation. Combination index-isobologram analysis indicates a synergistic effect between LASSBio-1386 and dexamethasone in lymphoproliferation inhibition. LASSBio-1386 presented immunomodulatory action in macrophage cultures, as observed by a significant and concentration-dependent decrease in NO and TNF-α production, an effect achieved by reducing IĸB expression and NF-κB activation. In the mouse model of endotoxic shock, LASSBio-1386 at 50 and 100 mg/kg protected 50 and 85% of mice against LPS-induced lethality, respectively. In agreement to its in vitro action, treatment with 100 mg/kg of LASSBio-1386 reduced TNF-α and IL-1β serum levels, while increased IL-6 and IL-10. Finally, LASSBio-1386 reduced the paw edema in a BSA-induced delayed-type hypersensitivity model. These findings demonstrate the immunomodulatory and immunosuppressant effects of LASSBio-1386 and indicate this molecule is a promising pharmacologic agent for immune-mediated diseases. Graphical abstract Unlabelled Image Highlights • LASSBio-1386 suppresses lymphocyte proliferation, cytokine secretion and in vivo delayed-type hypersensitivity. • The mechanism behind lymphocyte suppression is independent of glucocorticoid cascade. • LASSBio–1386 achieved immunomodulation by impairing NF-κB activation. [ABSTRACT FROM AUTHOR]

Over the last two decades, N -acylhydrazone (NAH) has been proven to be a very versatile and promising motif in drug design and medicinal chemistry. Herein, we discuss the current and future challenges in the emergence of bioactive NAH-based scaffolds and to developing strategies to overcome the failures in drug discovery. The NAH-related approved drugs nitrofurazone , nitrofurantoin , carbazochrome , testosterone 17-enanthate 3-benzilic acid hydrazine, nifuroxazide, dantrolene, and azumolene are already used as therapeutics in various countries. PAC-1 is an NAH-based therapeutic agent that entered clinical trials in 2015. Another NAH-derived scaffold, LASSBio-294 , is in preclinical trials. This review highlights the detailed comprehensive assessment and therapeutic landscape of bioactive NAH motif scaffolds in preclinical and clinical studies published to date and their promise and associated challenges in current and future drug discovery of NAH-based drugs that will progress to clinical use. [ABSTRACT FROM AUTHOR]

Piperazine is a promising scaffold for drug development due to its broad spectrum of biological activities. Based on this, the new piperazine-containing compound LQFM018 ( 2 ) [ethyl 4-((1-(4-chlorophenyl)-1H-pyrazol-4-yl)methyl)piperazine-1-carboxylate] was synthetized and some biological activities investigated. In this work, we described its ability to bind aminergic receptors, antiproliferative effects as well as the LQFM018 ( 2 )-triggered cell death mechanisms, in K562 leukemic cells, by flow cytometric analyses. Furthermore, acute oral systemic toxicity and potential myelotoxicity assessments of LQFM018 ( 2 ) were carried out. LQFM018 ( 2 ) was originally obtained by molecular simplification from LASSBio579 ( 1 ), an analogue compound of clozapine, with 33% of global yield. Binding profile assay to aminergic receptors showed that LQFM018 ( 2 ) has affinity for the dopamine D 4 receptor ( K i  = 0.26 μM). Moreover, it showed cytotoxicity in K562 cells, in a concentration and time-dependent manner; IC 50 values obtained were 399, 242 and 119 μM for trypan blue assay and 427, 259 and 50 μM for MTT method at 24, 48 or 72 h, respectively. This compound (427 μM) also promoted increase in LDH release and cell cycle arrest in G2/M phase. Furthermore, it triggered necrotic morphologies in K562 cells associated with intense cell membrane rupture as confirmed by Annexin V/propidium iodide double-staining. LQFM018 ( 2 ) also triggered mitochondrial disturb through loss of ΔΨm associated with increase of ROS production. No significant accumulation of cytosolic cytochrome c was verified in treated cells. Furthermore, it was verified an increase of expression of TNF-R1 and mRNA levels of CYLD with no involviment in caspase-3 and -8 activation and NF-κB in K562 cells. LQFM018 ( 2 ) showed in vitro myelotoxicity potential, but it was orally well tolerated and classified as UN GHS category 5 (LD 50  > 2000–5000 mg/Kg). Thus, LQFM018 ( 2 ) seems to have a non-selective action considering hematopoietic cells. In conclusion, it is suggested LQFM018 ( 2 ) promotes cell death in K562 cells via necroptotic signaling, probably with involvement of dopamine D 4 receptor. These findings open new perspectives in cancer therapy by use of necroptosis inducing agents as a strategy of reverse cancer cell chemoresistance. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary hypertension (PH) is characterized by enhanced pulmonary vascular resistance, which causes right ventricle (RV) pressure overload and results in right sided heart failure and death. This work investigated the effectiveness of a combined therapy with PDE5 inhibitor (PDE5i) and a new adenosine A2A receptor (A2AR) agonist in mitigating monocrotaline (MCT) induced PH in rats. Methods: An in vitro isobolographic analysis was performed to identify possible synergistic relaxation effect between sildenafil and LASSBio 1359 in rat pulmonary arteries (PAs). In the in vivo experiments, PH was induced in male Wistar rats by a single intraperitoneal injection of 60 mg/kg MCT. Rats were divided into the following groups: control (saline injection only), MCT + vehicle, MCT + sildenafil, MCT + LASSBio 1359 and MCT + combination of sildenafil and LASSBio 1359. Fourteen days after the MCT injection, rats were treated daily with oral administration of the regimen therapies or vehicle for 14 days. Cardiopulmonary system function and structure were evaluated by echocardiography. RV systolic pressure and PA endothelial function were measured. Results: Isobolographic analysis showed a synergistic interaction between sildenafil and LASSBio 1359 in rat PAs. Combined therapy with sildenafil and LASSBio 1359 but not monotreatment with low dosages of either sildenafil or LASSBio 1359 ameliorated all of PH related abnormalities in cardiopulmonary function and structure in MCT challenged rats. Conclusions: The combination of sildenafil and LASSBio 1359 has a synergistic interaction, suggesting that combined use of these pharmacological targets may be an alternative to improve quality of life and outcomes for PH patients. [ABSTRACT FROM AUTHOR]

Microcystins-LR (MC-LR) is a cyanotoxin produced by cyanobacteria. We evaluated the antioxidant potential of LASSBio-596 (LB-596, inhibitor of phosphodiesterases 4 and 5), per os , and biochemical markers involved in lung and liver injury induced by exposure to sublethal dose of MC-LR. Fifty male Swiss mice received an intraperitoneal injection of 60 μL of saline (CTRL group, n = 20) or a sublethal dose of MC-LR (40 μg/kg, TOX group, n = 20). After 6 h the animals received either saline (TOX and CTRL groups) or LB-596 (50 mg/kg, TOX + LASS group, n = 10) by gavage. At 6 h after exposure, respiratory mechanics was evaluated in 10 CTRL and 10 TOX mice: there was a significant increase of all lung mechanics parameters (static elastance, viscoelastic component of elastance and lung resistive and viscoelastic/inhomogeneous pressures) in TOX compared to CTRL. 8 h after saline or MC-LR administration, i.e., 2 h after treatment with LB-596, blood serum levels of alanine aminotransferase and aspartate aminotransferase, activity of superoxide dismutase, catalase, and content of malondialdehyde and carbonyl in lung and liver, NADPH oxidase 2 and 4 mRNA expressions, dual oxidase enzyme activity and H 2 O 2 generation were analyzed in lung homogenates. All parameters were significantly higher in TOX than in the other groups. There was no significant difference between CTRL and TOX + LASS. MC-LR deteriorated lung and liver functions and induced redox imbalance in them, which was prevented by oral administration of LB-596. [ABSTRACT FROM AUTHOR]

Protein kinases constitute attractive therapeutic targets for development of new prototypes to treat different chronic diseases. Several available drugs, like tinibs, are tyrosine kinase inhibitors; meanwhile, inhibitors of serine/threonine kinases, such as mitogen‐activated protein kinase (MAPK), are still trying to overcome some problems in one of the steps of clinical development to become drugs. So, here we reported the synthesis, the in vitro kinase inhibitory profile, docking studies, and the evaluation of anti‐inflammatory profile of new naphthyl‐N‐acylhydrazone derivatives using animal models. Although all tested compounds (3a–d) have been characterized as p38α MAPK inhibitors and have showed in vivo anti‐inflammatory action, LASSBio‐1824 (3b) presented the best performance as p38α MAPK inhibitor, with IC50 = 4.45 μ m, and also demonstrated to be the most promising anti‐inflammatory prototype, with good in vivo anti‐TNF‐α profile after oral administration. [ABSTRACT FROM AUTHOR]

It is well known that combretastatin A4 (CA-4), which is a natural stilbene isolated from Combretum caffrum , is used to inhibit angiogenesis. However, depending on the dose administered to the patient, it can cause some side-effects. Herein, we present the synthesis and structural characterization of a novel N -acylhydrazone derivative – LASSBio-1735 – a CA-4 analogue. LASSBio-1735 has displayed in vitro antiproliferative activity against HL-60 (human leukemia), SF-295 (human glioblastoma), MDA-MB435 (melanoma) and HCT-8 (ileocecal adenocarcinoma) tumor cells. We found different hydration levels in two batches of the as-synthesized compound. As a consequence, we could successfully determine the crystal structures – by using X-ray powder diffraction data and a simulated annealing procedure – of the anhydrous and hydrated forms. The effects on cell viability of anhydrous and hydrated forms of LASSBio-1735 were comparatively evaluated in different tumor cell lines, and the hydrated form exhibited higher cytotoxicity in human leukemia K562 cells. These findings lead us to perform a quantitative phase analysis on one of the samples and may shed some light on the search for possible new solvates and/or hydrates. [ABSTRACT FROM AUTHOR]

LASSBio-1755 is a new cycloalkyl- N -acylhydrazone parent compound designed for the development of derivatives with antinociceptive and anti-inflammatory activities. Although single crystal X-ray diffraction has been considered as the golden standard in structure determination, we successfully used X-ray powder diffraction data in the structural determination of new synthesized compounds, in order to overcome the bottle-neck due to the difficulties experienced in harvesting good quality single crystals of the compounds. We therefore unequivocally assigned the relative configuration ( E ) to the imine double bond and a s- cis conformation of the amide function of the N -acylhydrazone compound. These features are confirmed by a computational analysis performed on the basis of molecular dynamics calculations, which are extended not only to the structural characteristics but also to the analysis of the anisotropic atomic displacement parameters, a further information – missed in a typical powder diffraction analysis. The so inferred data were used to perform additional cycles of refinement and eventually generate a new cif file with additional physical information. Furthermore, crystal morphology prediction was performed, which is in agreement with the experimental images acquired by scanning electron microscopy, thus providing useful information on possible alternative paths for better crystallization strategies. [ABSTRACT FROM AUTHOR]

In this work, we present the physicochemical characterization and structural determination of two sulfonylhydrazone derivatives: LASSBio-1773 and LASSBio-1774. The former compound has displayed hypoglycemic activity and has reduced the thermal hyperalgesia and mechanical allodynia in a murine model of diabetic neuropathic pain induced by streptozotocin. In order to stablish the differences in the three-dimensional characteristics of these original bioactive compounds, we determined their crystal structures – by using X-ray powder diffraction data and a simulated annealing procedure – and studied their thermal stability. Furthermore, we performed crystal morphology prediction and compared it with SEM photomicrographs: the evidenced good agreement allowed us to suggest alternative crystallization routes – to overcome the low-solubility of LASSBio-1773 and LASSBio-1774 – as evidenced by IDR tests. [ABSTRACT FROM AUTHOR]

Prior investigations showed that increased levels of cyclic AMP down-regulate lung inflammatory changes, stimulating the interest in phosphodiesterase (PDE)4 as therapeutic target. Here, we described the synthesis, pharmacological profile and docking properties of a novel sulfonamide series (5 and 6a-k) designed as PDE4 inhibitors. Compounds were screened for their selectivity against the four isoforms of human PDE4 using an IMAP fluorescence polarized protocol. The effect on allergen- or LPS-induced lung inflammation and airway hyper-reactivity (AHR) was studied in A/J mice, while the xylazine/ketamine-induced anesthesia test was employed as a behavioral correlate of emesis in rodents. As compared to rolipram, the most promising screened compound, 6a (LASSBio-448) presented a better inhibitory index concerning PDE4D/PDE4A or PDE4D/PDE4B. Accordingly, docking analyses of the putative interactions of LASSBio-448 revealed similar poses in the active site of PDE4A and PDE4C, but slight unlike orientations in PDE4B and PDE4D. LASSBio-448 (100 mg/kg, oral), 1 h before provocation, inhibited allergen-induced eosinophil accumulation in BAL fluid and lung tissue samples. Under an interventional approach, LASSBio-448 reversed ongoing lung eosinophilic infiltration, mucus exacerbation, peribronchiolar fibrosis and AHR by allergen provocation, in a mechanism clearly associated with blockade of pro-inflammatory mediators such as IL-4, IL-5, IL-13 and eotaxin-2. LASSBio-448 (2.5 and 10 mg/kg) also prevented inflammation and AHR induced by LPS. Finally, the sulfonamide derivative was shown to be less pro-emetic than rolipram and cilomilast in the assay employed. These findings suggest that LASSBio-448 is a new PDE4 inhibitor with marked potential to prevent and reverse pivotal pathological features of diseases characterized by lung inflammation, such as asthma. [ABSTRACT FROM AUTHOR]

We report on the synthesis of novel Ru(II) compounds (Ru-1 to Ru-8) bearing R-pdc, 4-Cl-pbinh ligands (where R = 4-CF 3 , 4-F, 4-OH pdc = 3-phenyl-5-(1H-pyrrol-2-yl)-4,5-dihydro-1H-pyrazole-1-carbothioamide, pbinh = phenoxybenzylidene isonicotinyl hydrazides) and their in vitro antitumor activity toward the cell lines murine leukemia L1210, human lymphocyte CEM, human epithelial cervical carcinoma HeLa, BEL-7402 and Molt4/C8. Some of the complexes exhibited more potent antiproliferative activity against cell lines than the standard drug cisplatin. Ruthenium complex Ru-2 displayed potent cytotoxicity with than that of cisplatin. DNA-binding, DNA cleavage and protein binding properties of ruthenium complexes with these ligands are reported. Interactions of these ruthenium complexes with DNA revealed an intercalative mode of binding between them. Synchronous fluorescence spectra proved that the interaction of ruthenium complexes with bovine serum albumin (BSA) resulted in a conformational change of the latter. [ABSTRACT FROM AUTHOR]

In an attempt to better understand the molecular mechanism of action of the antipsychotic lead LASSBio-579 and of its main metabolite LQFM 037, the aim of this work was to evaluate their intrinsic activity and binding kinetics at the dopamine D 2 receptor. In transfected HEK cells expressing the D 2L receptor under an inducible promoter, LASSBio-579 and LQFM 037, but not clozapine, behaved as weak partial agonists in [ 35 S]-GTPγS binding assays performed in optimized conditions previously shown to evidence the partial agonist profile of aripiprazole. Besides, data obtained in radioligand competition assays on rat striatal membranes suggested a rapid association to and dissociation from the D 2 -like receptors. Using the kinetic rate index based on the strategy of the dual-point competition association assay, we showed that our compounds share a similar kinetic profile with clozapine, distinct from the typical antipsychotic haloperidol. These two characteristics could contribute to the atypical-like profile observed after administration of LASSBio-579 to rodents, in models of positive and negative symptoms of schizophrenia. [ABSTRACT FROM AUTHOR]

Trypanosomatids are protozoan parasites that cause various diseases in human, such as leishmaniasis, Chagas disease and sleeping sickness. The highly syntenic genomes of the trypanosomatid species lead the assumption that they can encode similar proteins, indicating the possibility to design new antitrypanosomatid drugs with dual trypanosomicidal and leishmanicidal activities. In this work a series of compounds ( 6a–h and 7a–h ), containing a semicarbazone scaffold as a peptide mimetic framework, was designed and synthesized. From this series compound 7g (LASSBio-1483) highlighted, showing dual in vitro trypanosomicidal and leishmanicidal activities, with potency similar to the standard drugs nifurtimox and pentamidine. This data, taken together with its good in silico druglikeness profile and its great chemical and plasma stability, make LASSBio-1483 ( 7g ) a new antitrypanosomatid lead-candidate. [ABSTRACT FROM AUTHOR]

The N-acylhydrazone (NAH) moiety is considered a privileged structure, being present in many compounds with diverse pharmacological activities. Among the activities attributed to NAH derivatives anti-inflammatory and analgesic ones are recurrent. As part of a research program aiming at the design of new analgesic and anti-inflammatory lead-candidates, a series of cyclohexyl-N-acylhydrazones 10-26 were structurally designed from molecular modification on the prototype LASSBio-294, representing a new class of cycloalkyl analogues. Compounds 10-26 and their conformationally restricted analogue 9 were synthetized and evaluated as analgesic and anti-inflammatory agents in classical pharmacologic protocols. The cyclohexyl-N-acylhydrazones 10-26 and the cyclohexenyl analogue 9 showed great anti-inflammatory and/or analgesic activities, but compound 13 stood out as a new prototype to treat acute and chronic painful states due to its important analgesic activity in a neuropathic pain model. [ABSTRACT FROM AUTHOR]

LASSBio-1289 compound has been found to promote intense vasodilation and antihypertensive activity. It is an innovative compound, without structural similarities to the three main classes of calcium antagonists (1,4-dihydropyridines, benzothiazepines and phenylalkylamines) commonly used. A complete knowledge of the structure, including stereochemistry, is essential to lead optimization in drug discovery. For this reason, in this work we determined the crystal structure of this novel vasoactive N-methyl-N-acylhydrazone derivative by means of X-ray powder diffraction data and an ab initio simulating annealing approach, allowing us to observe the relative configuration E of the imine double bond and its conformation as well as its most relevant intermolecular interactions. These findings were also checked by a FTIR analysis and confirmed in solution by NMR. The compound crystallized under a monoclinic crystal system with space group P21/c and unit cell parameters a = 14.5118(3) Å, b = 12.1374(2) Å, c = 7.5498(1) Å, ß = 91.113(1)°, V = 1329.53(4) ų, Z = 4, Z' = 1 and ?calc = 1.44042(4) g cm-3. Moreover, a crystal morphology prediction, experimentally compared with SEM inferred images, allowed a direct comparison of the microcrystalline habit and quality, allowing a study of the potential solvent effect on the crystal growth. [ABSTRACT FROM AUTHOR]

Different chemotypes are described as anti-inflammatory. Among them the N-acylhydrazones (NAH) are highlighted by their privileged structure nature, being present in several anti-inflammatory drug-candidates. In this paper a series of functionalized 3-aminothiophene-2-acylhydrazone derivatives 5a-i were designed, synthesized and bioassayed. These new derivatives showed great anti-inflammatory and analgesic potency and efficacy. Compounds 5a and 5d stand out in this respect, and were also active in CFA-induced arthritis in rats. After daily treatment for seven days with 5a and 5d (50 μmol/Kg), by oral administration, these compounds were not renal or hepatotoxic nor immunosuppressive. Compounds 5a and 5d also displayed good drug-scores and low risk toxicity calculated in silico using the program OSIRIS Property Explorer. [ABSTRACT FROM AUTHOR]

LASSBio-1135 is an imidazo[1,2-a]pyridine derivative with high efficacy in screening models of nociception and inflammation, presumed as a weak COX-2 inhibitor. In order to tease out its mechanism of action, we investigated others possible target for LASSBio-1135, such as TNF-α and TRPV1, to better characterize it as a multitarget compound useful in the treatment of chronic pain. TRPV1 modulation was assessed in TRPV1-expressing Xenopus oocytes against capsaicin and low pH-induced current. Modulation of TNF-α production was evaluated in culture of macrophages stimulated with LPS. In vivo efficacy of LASSBio-1135 was investigated in carrageenan and partial sciatic ligation-induced thermal hyperalgesia and mechanical allodynia. Corroborating its previous demonstration of efficacy in a model of capsaicin-induced hyperalgesia, LASSBio-1135 blocks capsaicin-elicited currents in a non-competitive way with an IC50 of 580 nM as well as low pH-induced current at 50 µM. As an additional action, LASSBio-1135 inhibited TNF-α release in these cells stimulated by LPS with an IC50 of 546 nM by reducing p38 MAPK phosphorilation. Oral administration of 100 µmol.Kg−1 LASSBio-1135 markedly reduced thermal hyperalgesia induced by carrageenan, however at 10 µmol.Kg−1 only a partial reduction was observed at the 4th h. Neutrophil recruitment and TNF-α production after carrageenan stimulus was also inhibited by the treatment with LASSBio-1135. Modulating TRPV1 and TNF-α production, two key therapeutic targets of neuropathic pain, 100 µmol.Kg−1 LASSBio-1135 was orally efficacious in reversing thermal hyperalgesia and mechanical allodynia produced by partial sciatic ligation 7–11 days after surgery without provoking hyperthermia, a common side effect of TRPV1 antagonists. In conclusion LASSBio-1135, besides being a weak COX-2 inhibitor, is a non-competitive TRPV1 antagonist and a TNF-α inhibitor. As a multitarget compound, LASSBio-1135 is orally efficacious in a model of neuropathic pain without presenting hyperthermia. [ABSTRACT FROM AUTHOR]

Abstract: Background: Pulmonary arterial hypertension (PAH) is a disease that results in right ventricular (RV) dysfunction. While pulmonary vascular disease is the primary pathological focus, RV hypertrophy and RV dysfunction are the major determinants of prognosis in PAH. The aim of this study was to investigate the effects of (E)-N′-(3,4-dimethoxybenzylidene)-4-methoxybenzohydrazide (LASSBio-1386), an N-acylhydrazone derivative, on the lung vasculature and RV dysfunction induced by experimental PAH. Methods: Male Wistar rats were injected with a single dose (60mg/kg, i.p.) of monocrotaline (MCT) and given LASSBio-1386 (50mg/kg, p.o.) or vehicle for 14days. The hemodynamic, exercise capacity (EC), endothelial nitric oxide synthase (eNOS), adenosine A2A receptor (A2AR), sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA2a), phospholamban (PLB) expression, Ca2+-ATPase activity and vascular activity of LASSBio-1386 were evaluated. Results and conclusions: The RV systolic pressure was elevated in the PAH model and reduced from 49.6±5.0mmHg (MCT group) to 27.2±2.1mmHg (MCT+LASSBio-1386 group; P <0.05). MCT administration also impaired the EC, increased the RV and pulmonary arteriole size, and promoted endothelial dysfunction of the pulmonary artery rings. In the PAH group, the eNOS, A2AR, SERCA2a, and PLB levels were changed compared with the control; in addition, the Ca2+-ATPase activity was reduced. These alterations were related with MCT-injected rats, and LASSBio-1386 had favorable effects that prevented the development of PAH. LASSBio-1386 is effective at preventing endothelial and RV dysfunction in PAH, a finding that may have important implications for ongoing clinical evaluation of A2AR agonists for the treatment of PAH. [Copyright &y& Elsevier]

In this work, we describe the design, synthesis and pharmacological evaluation of novel imidazo[1,2-a]pyridine-N-glycinyl-hydrazone derivatives (1a–k) intended for use as inhibitors of tumor necrosis factor alpha (TNF-α) production. The compounds were designed based on the orally active anti-inflammatory prototype LASSBio-1504 (2), which decreases the levels of the pro-inflammatory cytokine TNF-α in vitro and in vivo. The in vitro pharmacological evaluation of the imidazo[1,2-a]pyridine compounds (1) showed that substitution of the N-phenylpyrazole core present in prototype 2 by a bioisosteric imidazo[1,2-a]pyridine scaffold generated anti-TNF-α compounds that were more potent than the previously described N-phenylpyrazole derivative 2 and as potent as SB-203580, a p38 MAPK inhibitor. The most active derivative (E)-2-(2-tert-butylimidazo[1,2-a]pyridin-3-ylamino)-N’-(4-chlorobenzylidene) acetohydrazide, or LASSBio-1749 (1i) was orally active as an anti-inflammatory agent in a subcutaneous air pouch model, reducing expressively the levels in vivo of TNF-α and other pro-inflammatory cytokines at all of the tested doses. [ABSTRACT FROM AUTHOR]

Cancer is the second most common cause of death in the USA. Among the known classes of anticancer agents, the microtubule-targeted antimitotic drugs are considered to be one of the most important. They are usually classified into microtubule-destabilizing (e.g., Vinca alkaloids) and microtubule-stabilizing (e.g., paclitaxel) agents. Combretastatin A4 (CA-4), which is a natural stilbene isolated from Combretum caffrum, is a microtubule-destabilizing agent that binds to the colchicine domain on β-tubulin and exhibits a lower toxicity profile than paclitaxel or the Vinca alkaloids. In this paper, we describe the docking study, synthesis, antiproliferative activity and selectivity index of the N-acylhydrazone derivatives (5a–r) designed as CA-4 analogues. The essential structural requirements for molecular recognition by the colchicine binding site of β-tubulin were recognized, and several compounds with moderate to high antiproliferative potency (IC50 values ≤18 µM and ≥4 nM) were identified. Among these active compounds, LASSBio-1586 (5b) emerged as a simple antitumor drug candidate, which is capable of inhibiting microtubule polymerization and possesses a broad in vitro and in vivo antiproliferative profile, as well as a better selectivity index than the prototype CA-4, indicating improved selective cytotoxicity toward cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: Novel 2-chloro-4-anilino-quinazolines designed as EGFR and VEGFR-2 dual inhibitors were synthesized and evaluated for inhibitory effects. EGFR and VEGFR-2 are validated targets in cancer therapy and combined inhibition might be synergistic for both antitumor activity and resistance prevention. The biological data obtained proved the potential of 2-chloro-4-anilino-quinazoline derivatives as EGFR and VEGFR-2 dual inhibitors, highlighting compound 8o, which was approximately 7-fold more potent on VEGFR-2 and approximately 11-fold more potent on EGFR compared to the prototype 7. SAR and docking studies allowed the identification of pharmacophoric groups for both kinases and demonstrated the importance of a hydrogen bond donor at the para position of the aniline moiety for interaction with conserved Glu and Asp amino acids in EGFR and VEGFR-2 binding sites. [Copyright &y& Elsevier]

Herein we describe NMR experiments and structural modifications of 4-methyl-2-phenylpyrimidine-N-acylhydrazone compounds (aryl-NAH) in order to discover if duplication of some signals in their 1H- and 13C-NMR spectra was related to a mixture of imine double bond stereoisomers (E/Z) or CO-NH bond conformers (syn and anti-periplanar). NMR data from NOEdiff, 2D-NOESY and 1H-NMR spectra at different temperatures, and also the synthesis of isopropylidene hydrazone revealed the nature of duplicated signals of a 4-methyl-2-phenylpyrimidine-N-acylhydrazone derivative as a mixture of two conformers in solution. Further we investigated the stereoelectronic influence of substituents at the ortho position on the pyrimidine ring with respect to the carbonyl group, as well as the electronic effects of pyrimidine by changing it to phenyl. The conformer equilibrium was attributed to the decoplanarization of the aromatic ring and carbonyl group (generated by an ortho-alkyl group) and/or the electron withdrawing character of the pyrimidine ring. Both effects increased the rotational barrier of the C-N amide bond, as verified by the ΔG≠ values calculated from dynamic NMR. As far as we know, it is the first description of aryl-NAH compounds presenting two CO-NH bond- related conformations. [ABSTRACT FROM AUTHOR]

Abstract: In an attempt to increase the affinity of our antipsychotic lead compound LASSBio-579 (1-((1-(4-chlorophenyl)-1H-pyrazol-4-yl)methyl)-4-phenylpiperazine; (2)) for the 5-HT2A receptor, we synthesized five new N-phenylpiperazine derivatives using a linear synthetic route and the homologation strategy. The binding profile of these compounds was evaluated for a series of dopaminergic, serotonergic and alpha-adrenergic receptors relevant for schizophrenia, using classical competition assays. Increasing the length of the spacer between the functional groups of (2) proved to be appropriated since the affinity of these compounds increased 3–10-fold for the 5-HT2A receptor, with no relevant change in the affinity for the D2-like and 5-HT1A receptors. A GTP-shift assay also indicated that the most promising derivative (1-(4-(1-(4-chlorophenyl)-1H-pyrazol-4-yl) butyl)-4-phenylpiperazine) (LASSBio-1635) (6) has the expected efficacy at the 5-HT2A receptors, acting as an antagonist. Intraperitoneal administration of (6) prevented apomorphine-induced climbing behavior and ketamine-induced hyperlocomotion in mice, in a dose dependent manner. Together, these results show that (6) could be considered as a new antipsychotic lead compound. [Copyright &y& Elsevier]

New chemicals or adjuvants with analgesic effects on chronic pain are needed and clinically relevant due to the limited number of effective compounds that possess these characteristics. LASSBio-873, a pyrazolo[3,4- b]pyrrolo[3,4- d]pyridine derivative, activates muscarinic cholinergic receptors and has potent analgesic effects on acute and inflammatory pain., The present study evaluated the therapeutic and prophylactic effects of oral administration of LASSBio-873 in a spinal nerve ligation ( SNL) model of chronic peripheral nerve injury., LASSBio-873 (100 mg/kg) inhibited the development of thermal hyperalgesia and mechanical allodynia when administered once daily for 7 consecutive days after SNL surgery and reversed these symptoms. LASSBio-873 treatment did not alter rat behaviour in open field testing measured during the first 24 h after administration and again after 7 continuous days administration. The analgesic effect of LASSBio-873 was inhibited by intrathecal methoctramine, an M2 receptor antagonist, implicating the muscarininc M2 receptor signalling pathway in the drug's action., These results reinforce the potential of LASSBio-873 as a possible prototype for the development of more effective alternatives for the treatment of neuropathic pain. [ABSTRACT FROM AUTHOR]

Background and Purpose: Pulmonary arterial hypertension (PAH) is characterized by enhanced pulmonary vascular resistance, right ventricular hypertrophy and increased right ventricular systolic pressure. Here, we investigated the effects of a N-acylhydrazone derivative, 3,4-dimethoxyphenyl-N-methyl-benzoylhydrazide (LASSBio-1359), on monocrotaline (MCT)-induced pulmonary hypertension in rats.Experimental Approach: PAH was induced in male Wistar rats by a single i.p. injection of MCT (60 mg·kg(-1)) and 2 weeks later, oral LASSBio-1359 (50 mg·kg(-1)) or vehicle was given once daily for 14 days. Echocardiography was used to measure cardiac function and pulmonary artery dimensions, with histological assay of vascular collagen. Studies of binding to human recombinant adenosine receptors (A1, A2A, A3) and of docking with A2A receptors were also performed.Key Results: MCT administration induced changes in vascular and ventricular structure and function, characteristic of PAH. These changes were reversed by treatment with LASSBio-1359. MCT also induced endothelial dysfunction in pulmonary artery, as measured by diminished relaxation of pre-contracted arterial rings, and this dysfunction was reversed by LASSBio-1359. In pulmonary artery rings from normal Wistar rats, LASSBio-1359 induced relaxation, which was decreased by the adenosine A2A receptor antagonist, ZM 241385. In adenosine receptor binding studies, LASSBio-1359 showed most affinity for the A2A receptor and in the docking analyses, binding modes of LASSBio-1359 and the A2A receptor agonist, CGS21680, were very similar.Conclusion and Implications: In rats with MCT-induced PAH, structural and functional changes in heart and pulmonary artery were reversed by treatment with oral LASSBio-1359, most probably through the activation of adenosine A2A receptors. [ABSTRACT FROM AUTHOR]

Background and Purpose Pulmonary arterial hypertension (PAH) is characterized by enhanced pulmonary vascular resistance, right ventricular hypertrophy and increased right ventricular systolic pressure. Here, we investigated the effects of a N-acylhydrazone derivative, 3,4-dimethoxyphenyl- N-methyl-benzoylhydrazide ( LASSBio-1359), on monocrotaline (MCT)-induced pulmonary hypertension in rats. Experimental Approach PAH was induced in male Wistar rats by a single i.p. injection of MCT (60 mg·kg−1) and 2 weeks later, oral LASSBio-1359 (50 mg·kg−1) or vehicle was given once daily for 14 days. Echocardiography was used to measure cardiac function and pulmonary artery dimensions, with histological assay of vascular collagen. Studies of binding to human recombinant adenosine receptors (A1, A2A, A3) and of docking with A2A receptors were also performed. Key Results MCT administration induced changes in vascular and ventricular structure and function, characteristic of PAH. These changes were reversed by treatment with LASSBio-1359. MCT also induced endothelial dysfunction in pulmonary artery, as measured by diminished relaxation of pre-contracted arterial rings, and this dysfunction was reversed by LASSBio-1359. In pulmonary artery rings from normal Wistar rats, LASSBio-1359 induced relaxation, which was decreased by the adenosine A2A receptor antagonist, ZM 241385. In adenosine receptor binding studies, LASSBio-1359 showed most affinity for the A2A receptor and in the docking analyses, binding modes of LASSBio-1359 and the A2A receptor agonist, CGS21680, were very similar. Conclusion and Implications In rats with MCT-induced PAH, structural and functional changes in heart and pulmonary artery were reversed by treatment with oral LASSBio-1359, most probably through the activation of adenosine A2A receptors. [ABSTRACT FROM AUTHOR]

Abstract: Using a combination of docking and molecular dynamics simulations, we predicted that p-hydroxylation by CYP1A2 would be the main metabolic pathway for the 1-[1-(4-chlorophenyl)-1H-4pyrazolylmethyl] phenylhexahydropiperazine, LASSBio-579 (3). As the result of a screening process with strains of filamentous fungi, Cunninghamella echinulata ATCC 9244 was chosen to scale up the preparation of the p-hydroxylated metabolite (4). About 30 min after i.p. administration of (3) to rats was identified as the p-hydroxylated metabolite, confirming our in silico previsions. Chemical synthesis of the metabolite was performed and allowed its pharmacological evaluation in binding assays revealing its high affinity for D2 and D4 receptors, indicating that this metabolite should participate to the antipsychotic effect of (3) in vivo. Furthermore, we report here that both (3) and its p-hydroxylated metabolite (4) have a much lower affinity than clozapine for two receptors involved in adverse reactions. Voltammetric assays were useful to understand the redox profile of (3). [Copyright &y& Elsevier]

Abstract: Searching for new promising metal-based hits against Trypanosoma cruzi and Leishmania parasites, two related oxidovanadium(IV) N-acylhydrazone complexes, [VIVO(LASSBio1064-2H)(H2O)], 1, and [VIVO(LASSBio1064-2H)(phen)]·(H2O), 2, where LASSBio1064=(E)-N′-(2-hydroxybenzylidene-4-chlorobenzohydrazide and phen = 1,10-phenanthroline, were synthesized and characterized in the solid state and in solution by elemental analysis, conductimetric measurements and ESI-MS, FTIR, EPR and 51V NMR spectroscopies and were evaluated on T. cruzi and Leishmania major. In addition, their unspecific cytotoxicity was tested against murine macrophages. Furthermore, to provide insight into the possible mechanism of its antiparasitic action, [VO(LASSbio1064-2H)(phen)].(H2O) was tested for its DNA interaction ability on plasmid DNA by atomic force microscopy (AFM) and on CT DNA by using DNA viscosity measurements and fluorescence spectroscopy. Both complexes were active in vitro against the epimastigote form of T. cruzi (Tulahuen 2 strain) showing IC50 values of the same order or significantly lower than that of the reference trypanosomicidal drug Nifurtimox. However, only the mixed-ligand oxidovanadium(IV) complex 2, which includes phen in its coordination sphere, showed activity on L. major promastigotes with a IC50 value of 22.1 ± 0.6 μM. The compounds show low toxicity on mammalian cells (IC50 > 100 μM). DNA interaction studies showed that the mixed-ligand complex is able to interact with this biomolecule probably through an intercalative mode, pointing out at DNA as a potential target in the parasite. The results suggest that [VIVO(LASSBio1064-2H)(phen)]·(H2O) may be a promising compound for further drug development stages. [Copyright &y& Elsevier]

Abstract: Previous behavioral and receptor binding studies on N-phenylpiperazine derivatives by our group indicated that LASSBio-579, LASSBio-580 and LASSBio-581 could be potential antipsychotic lead compounds. The present study identified LASSBio-579 as the most promising among the three compounds, since it was the only one that inhibited apomorphine-induced climbing (5mg/kg p.o.) and apomorphine-induced hypothermia (15mg/kg p.o.). Furthermore, LASSBio-579 (0.5mg/kg p.o.) was effective in the ketamine-induced hyperlocomotion test and prevented the prepulse inhibition deficits induced by apomorphine, DOI and ketamine with different potencies (1mg/kg, 0.5mg/kg and 5mg/kg p.o., respectively). LASSBio-579 also induced a motor impairment, catalepsy and a mild sedative effect but only at doses 3–120 times higher than those with antipsychotic-like effects. In addition, LASSBio-579 (0.5 and 1mg/kg p.o.) reversed the catalepsy induced by WAY 100,635, corroborating its action on both dopaminergic and serotonergic neurotransmission and pointing to the contribution of 5-HT1A receptor activation to its pharmacological profile. Moreover, co-administration of sub-effective doses of LASSBio-579 with sub-effective doses of clozapine or haloperidol prevented the apomorphine-induced climbing without induction of catalepsy. In summary, our results characterize LASSBio-579 as a multi-target ligand active in pharmacological animal models of schizophrenia, confirming that this compound could be included in development programs aiming at a new drug for treating schizophrenia. [Copyright &y& Elsevier]

Abstract: Neglected diseases represent a major health problem. It is estimated that one third of the world population is infected with tuberculosis and additionally Leishmaniosis and Chagas disease affect approximately 30 million people. N-Acylhydrazone moiety is a repeated functional group present in several prototypes and drug candidates for these neglected diseases. On the other hand, furoxan system has been studied as pharmacophore for Leishmaniosis and Chagas diseases. Here we report on the design and preparation of forty hybrid furoxanyl N-acylhydrazones and on their activity on Mycobacterium tuberculosis, H37Rv and MDR strains, Trypanosoma cruzi, and Leishmania amazonensis. Among them, four derivatives displayed excellent to good selectivity indexes against the three different microorganisms. Hybrid compound N′-(4-phenyl-3-furoxanylmethylidene)isoniazide 9 showed the best antibacterial profile with MIC value 4.5 lesser than the value for the reference isoniazid against MDR strain. Furoxanyl N-acylhydrazone (E)-2-methyl-N′-(4-phenyl-3-furoxanylmethylidene)-4H-imidazo[1,2-a]pyridine-3-carbohydrazide 15 was ten-fold more potent against T. cruzi Amastigotes than the standard drug nifurtimox. On the other hand, derivatives (E)-N′-(5-benzofuroxanylmethylidene)benzo[d][1,3]dioxole-5-carbohydrazide 25 and (E)-N′-(4-hydroxy-3-methoxyphenylmethylidene)-3-methylfuroxan-4-carbohydrazide 37 emerged as leads for the development of new leishmanicidal agents. The adequate stability, in simulated biological system and plasma, and the lack of mutagenicity of these derivatives allow us to propose them as candidates for further pre-clinical studies. [Copyright &y& Elsevier]

In this paper we report the design, synthesis and pharmacological evaluation of a new series of phenyl sulfonamide derivatives 2a–h and 3–8 planned by structural modification on the anti-inflammatory prototype LASSBio-468 (1). Among the synthesized analogues, the tetrafluorophthalimide LASSBio-1439 (2e) stands out showing an in vitro anti-TNF-α effect similar to the standard thalidomide. The relevance of tetrafluorination of the phthalimide nucleus was also confirmed by the anti-inflammatory profile of 2e, through oral administration, in a murine model of pulmonary inflammation. The corresponding tetrafluorocarboxyamide metabolite LASSBio-1454 (15), generated from partial hydrolysis of the derivative 2e, presented a significant in vitro effect and a pronounced anti-inflammatory activity in vivo. [ABSTRACT FROM AUTHOR]

In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities of a series of benzothiazine N-acylhydrazones 14a-h, planned by structural modification of piroxicam (1), a non steroidal anti-inflammatory drug. Among the synthesized analogues, compounds 14f (LASSBio-1637) and 14g (LASSBio-1639) were identified as novel antinociceptive and anti-inflammatory prototypes, active by oral administration, acting by a mechanism of action that seems to be different from that of piroxicam, since they were inactive as an inhibitor of cyclooxygenase (COX-1 and COX-2) at concentrations of 10 μM. [ABSTRACT FROM AUTHOR]

Herein, we describe the synthesis and pharmacological evaluation of novel N-phenylpyrazolyl-N-glycinyl-hydrazone derivatives that were designed as novel prototypes of p38 mitogen-activated protein kinase (MAPK) inhibitors. All of the novel synthesized compounds described in this study were evaluated for their in vitro capacity to inhibit tumor necrosis factor a (TNF-α production in cultured macrophages) and in vitro MAPK p38a inhibition. The two most active anti-TNF-α derivatives, (E)-2-(3-tert-butyl-1-phenyl-1H-pyrazol-5-ylamino)-N'-((4-(2-morpholinoethoxy)naphthalen-1-yl)methylene)acetohydrazide (4a) and (E)-2-(3-tert-butyl-1-phenyl-1H-pyrazol-5-ylamino)-N'-(4-chlorobenzylidene)acetohydrazide (4f), were evaluated to determine their in vivo anti-hyperalgesic profiles in carrageenan-induced thermal hypernociception model in rats. Both compounds showed anti-inflammatory and antinociceptive properties comparable to SB-203580 used as a standard drug, by oral route at a dose of 100 µmol/kg. This bioprofile is correlated with the ability of NAH derivatives (4a) and (4f) suppressing TNF-α levels in vivo by 57.3 and 55.8%, respectively. [ABSTRACT FROM AUTHOR]

Aims: Evaluate the effect of LASSBio-596, structurally designed as a new hybrid of thalidomide, on inflammatory corneal angiogenesis. Methods: Eighteen rabbits were submitted to an alkaline cauterization in the right cornea. The animals were randomly allocated to three groups: vehicle, dexamethasone and LASSBio-596. Drugs were administered by eyedrops 3 times a day for 21 days. Evaluations were performed on days 3, 6, 9, 12, 15, 18 and 21 after cauterization. At these time points, digital images of the cornea were captured in a standard fashion. The angiogenic response was measured using software that was developed specifically for this purpose. It calculated the following parameters: neovascularization area (NA), total vascular length (TVL) and blood vessel number (BVN). Results: It was observed that dexamethasone significantly decreased NA, TVL and BVN during all assessments. From the NA the angiogenesis rate (AR) was calculated in each group. Therefore, dexamethasone completely inhibited the inflammatory corneal angiogenesis with an AR of -0.001 ± 0.006 mm2/day, which was significantly lower (p < 0.001) than that observed after treatment with vehicle (0.078 ± 0.024 mm2/day) and LASSBio-596 (0.054 ± 0.012 mm2/day). Although LASSBio-596 reduced angiogenesis in relation to vehicle, according to NA, TVL and BVN values, this difference was not statistically significant. However, it was found that the AR as measured in the LASSBio-596 group was significantly lower (p < 0.05) than that seen in control animals, indicating a potential antiangiogenic effect. Conclusion: We conclude that topical application of LASSBio-596 at 1.0% has a potential inhibitory effect on inflammatory corneal angiogenesis in rabbits. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Among a small series of tested N-acylhydrazones(NAHs), the compound 8awas selected as a selective submicromolarphosphodiesterase-4 (PDE4) inhibitor associated with anti-TNF-αproperties measured both in vitroand invivo. The recognition pattern of compound 8awas elucidated through molecular modeling studies based on the knowledgeof the 3D-structure of zardaverine, a PDE4 inhibitor resembling thestructure of 8a, cocrystallized with the PDE4. Basedon further conformational analysis dealing with N-methyl-NAHs, a quinazoline derivative (19) was designedas a conformationally constrained NAH analogue and showed similar in vitropharmacological profile, compared with 8a. In addition 19was found active when tested orallyin LPS-evoked airway hyperreactivity and fully confirmed the workinghypothesis supporting this work. [ABSTRACT FROM AUTHOR]

Abstract: p38 mitogen-activated protein kinase (p38 MAPK) is an important signal transducing enzyme involved in many cellular regulations, including signaling pathways, pain and inflammation. Several p38 MAPK inhibitors have been developed as drug candidates to treatment of autoimmune disorders, such as rheumatoid arthritis. In this paper we reported the docking, synthesis and pharmacological activity of novel urea-derivatives (4a–e) designed as p38 MAPK inhibitors. These derivatives presented good theoretical affinity to the target p38 MAPK, standing out compound 4e (LASSBio-998), which showed a better score value compared to the prototype GK-00687. This compound was able to reduce in vitro TNF-α production and was orally active in a hypernociceptive murine model sensible to p38 MAPK inhibitors. Otherwise, compound 4e presented a dose-dependent analgesic effect in a model of antigen (mBSA)-induced arthritis and anti-inflammatory profile in carrageenan induced paw edema, indicating its potential as a new antiarthritis prototype. [Copyright &y& Elsevier]