Heparanase (HPSE) is a mammalian endo-β-D-glucuronidase. It cleaves heparan sulphate (HS) side chains of heparin sulphate proteoglycans (HSPG), which are composed of repeating polysulfated disaccharide units of glucosamine and hexuronic acid residues. By degrading HS into smaller fractions, heparanase controls the availability of chemokines, growth factors and a plethora of other bioactive molecules, thus enabling the release of saccharide fragments that end up activating multitude of signaling processes. When overexpressed, HPSE has been correlated with tumor growth and survival as well as chronic inflammation exhibited in several diseases, the latest of them being the COVID-19 pandemic caused by SARS-CoV-2. Thus, it has become increasingly important in clinic to search for compounds that may potentially inhibit HPSE. In this study, we combined virtual screening and molecular docking of publicly known chemical databases in order to identify small molecules that can be developed into novel HPSE inhibitors. We were able to identify promising new chemotypes through the structural rationalization of the interactions previously reported compounds. These novel potential HPSE inhibitors are shown to exhibit optimized in silico druggability and docking properties and can potentially serve as pharmacological tools to treat chronic and infectious diseases associated with chronic inflammation.

As part of a project aimed to design and synthesize potential inhibitors of three enzymes overexpressed in head and neck cancer (2GS2, 1DDF, 1D2Q), five triazole derivatives of lawsone (2-hydroxy-1,4-naphtoquinone) stood out as the most promising in a virtual screening study of an in-house chemical library. Based on this, these five triazoles were synthesized to evaluate their activity against head and neck cancer cell lines. The synthesis was carried out in three steps, as follows. Initially, lawsone propargyl ether was obtained by reacting lawsone with propargyl bromide in alkaline medium. In parallel, the azides were prepared by diazotation of suitably substituted anilines followed by reacting the corresponding diazonium salts with sodium azide. Finally, the azido-alkyne cycloaddition reaction ("click" reaction) between lawsone propargyl ether and the azides provided the triazole derivatives of interest in general good yields. The biological evaluation of these compounds is underway and the results will be presented in due time.

Malaria is a parasitic disease considered one of the most serious public health problems in the world and was responsible in the previou year for the deaths of 627,000 people and 241 million cases diagnosed according to the 2021 World Malaria Report. The 1,4-naphthoquinones present a mechanism of inhibition of hemozoin formation and their action on the cycle of glutathione reductase of Plasmodium is related to their redox behavior. Because of these activities, 1,4-naphthoquinones are a class of interest in the search for new compounds with antimalarial activity. An important representative of this class is the 1,4- naphtoquinone derivative atovaquone, one of the drugs used in the treatment of malaria, whose mechanism of action is related to the structural similarity of this drug with ubiquinone. In the present work we prepared 2-O-propargyllawsone and 3-C-propargyllawsone wich were converted into the corresponding glycosyltriazole derivatives, using peracetylated and deacetylated glycosyl azides derived from D-glucose, D-galactose, D-N-acetilglucosamine and L-fucose. All the 16 glycosyltriazoles obtained and the two starting compounds were characterized by spectroscopic techniques and evaluated against chloroquine resistant strains (W2) of Plasmodium falciparum. Only 2-O-propargyllawsone (IC₅₀= 1.74 μM) and its glycosyltriazole derivatives diplayed activity, among which the peracetylated D-galactosyltriazole was the most active (IC₅₀= 3.16 μM). The corresponding deacetylated galactosyltriazole displayed IC₅₀= 7.60 μM,, indicating that acetylation improves the activity. The same trend was observed among the other glycosyltriazoles of this series.

Triple-negative breast cancer (TNBC) is an aggressive breast carcinoma with a poor prognosis. Current treatment options with platinum-(Pt)-based chemotherapeutics are limited by toxicity/acquired resistance, which prompted the search for novel metal-based compounds. The dinuclear palladium(II)-spermine chelate (Pd₂Spm) has previously shown promising pharmacokinetics and in vivo antitumor effects. However, its impact towards chemotherapy-resistant TNBC is still to be addressed. This work developed a cell model of cisplatin resistance and compared the anticancer/antiproliferative effects of cisplatin (reference Pt-based drug) and Pd₂Spm in TNBC cells sensitive (MDA-MB-231) and resistant to cisplatin (MDA-MB-231/R). Pd₂Spm displayed a similar antiproliferative potency in MDA-MB-231 and MDA-MB-231/R cells, while cisplatin showed ca. 18-fold lower potency towards MDA-MB-231/R cells. When focusing on cell death, incubation of Pd₂Spm with either Necrostatin-1 (necroptosis inhibitor), Z-VAD (apoptosis inhibitor) or 3-Methyladenine (3-MA, autophagy inhibitor) showed that 3-MA can rescue Pd₂Spm-induced growth inhibition in MDA-MB-231 and MDA-MB-231/R cells. Furthermore, in MDA-MB-231 cells, Pd₂Spm triggered higher LC3-II levels and more profound Beclin-1 inhibition than cisplatin. Regarding apoptosis, Pd₂Spm did not induce the cleavage of caspase-3 and co-incubation with both Pd₂Spm and Z-VAD yielded only marginal effects in preventing the phosphatidylserine externalization compared to cisplatin. Thus, the present data provided more evidence on Pd₂Spm’s cell death mechanisms, triggering a caspase-independent cell death with autophagy involvement. In addition, the potential of Pd₂Spm to overcome chemotherapy resistance is promising.

A series of novel thiophene pyrazolines were designed as potential bioactive molecules against Alzheimer’s disease. The probable binding modes of these molecules in AChE were evaluated by in silico techniques and promising molecules were then synthesized, characterized and biological activities were profiled to confirm their potential as multifunctional molecules for Alzheimer therapeutics addressing multiple pathological mechanisms. While the anti-oxidant activities of the synthesized molecules needs further optimization, the series as such showed excellent potential in mitigating the multiple causative factors viz Aβ aggregation inhibition, AChE inhibition, metal chelation and inhibition of advanced glycation products.

Beta-amino alcohols are versatile chemicals used as scaffolds in medicinal chemistry and are key factors for the efficacy of numerous pharmaceutical products. Locking the conformation of the active fragment in bioactive molecules may increase the potency and selectivity towards target receptor. Small rings especially the azetidine framework can serve as conformational lock yet providing the necessary size for receptor binding. Herein we report the synthesis of enantiopure beta-amino alcohols where the motif is combined with a structurally constrained azetidine cycle. The key steps towards target molecules include base-induced azetidine ring closure and subsequent beta-amino alcohol core installation.

Acknowledgements The research was funded by ERDF (Grant No. 1.1.1.2/VIAA/4/20/755)

Transforming Growth Factor- β Receptor type 1 (TGF-βR1) is an important anticancer target involved in promoting cell proliferation, progression and metastasis through induction of angiogenesis and suppression of immunological responses during the late stage of malignancy. Tranilast was initially approved for the treatment of bronchial asthma and allergic conditions in 1982. Later, it was revealed that Tranilast has numerous effects on cancer hallmarks, including immune evasion and sustained proliferation via inhibition of TGF-βR1. This research describes the design of a novel series of anthranilate derivatives having various modes of interactions with TGF-βR1 compared with Tranilast. A database of novel Tranilast analogues was generated using MOE software using Fragment-Based Drug Design. Representative compounds were selected from the database and docked in the identified binding site of TGF-βR1. Several compounds showed higher binding affinity for TGF-βR1 compared with the lead compound in this work, Tranilast. Compounds with high docking scores contained a positively charged amine group that interacted with Asp290 or a negatively charged carboxylate group with Lys 335 in the TGF-βR1 ATP binding site. Also, compounds containing an aromatic group showed high docking scores through interacting with Ser287, Lys337 or Ile 211. Compounds A11, A14, A16, and B5 which had the best poses in terms of binding interactions and docking scores to the binding site will be considered for further synthesis and biological evaluation.

Chalcones, a class of compounds characterized by two aromatic rings linked through a three carbon α,β-unsaturated carbonyl system, arouse widespread interest related to their (bio)synthesis and broad biological activities. However, less attention has been given to a subcategory of chalcones, bis-chalcones, despite some studies suggesting that they have improved bioactivities in comparison to their mono derivatives. Their synthesis is relatively less explored and typically requires longer reaction times and harder purifications, especially for derivatives with free hydroxy groups. This issue is relevant because several activities of bis chalcones have been associated to the presence of hydroxy groups in the structure.

In this context, the objectives of this work were to establish an efficient methodology for the synthesis of novel polyhydroxylated bis-chalcones and bis-chalcones containing other substituent groups such as halogen, methoxy, and prenyl groups and explore their chemical reactivity for further transformation into other potentially bioactive flavonoids.

Herein, we report our most recent results on the synthesis of bis-chalcones and their transformation into bis-flavones. Bis-chalcones were obtained in good yields (50-80%) by basic catalyzed Claisen–Schmidt condensation of MOM/Me-protected bis-acetophenones with aromatic aldehydes, followed by deprotection of MOM groups in an acidic medium. In turn, a prenylated bis-chalcone was prepared by O-prenylation of the hydroxylated bis-acetophenone followed by Claisen rearrangement and Claisen–Schmidt condensation with 4-methoxymethylbenzaldehyde. After, some unprotected bis-chalcones were successfully cyclized into bis-flavones through cyclodehydrogenation with I₂/DMSO. In the future we intend to evaluate the anti-inflammatory activity of these compounds.

Drug discovery relies on computational medicinal chemistry for designing and identifying new drug-like chemicals, predicting properties and pharmacological activities of molecules, and optimizing lead structures. Focal Adhesion Kinase (FAK) is an emerging target for cancer chemotherapy with mounting evidence that FAK activation or elevated expression is associated with cancer progression, invasion, and drug resistance. This work envisages identification and in silico screening of potential FAK inhibitors which could further be evaluated. A total of 862 compounds were screened from the ZINC database and docked on the refined FAK enzyme using Autodock Vina. The best spotted hits were filtered for their druglikeness using SwissADME. These potential hits were further evaluated for their in silico toxicity using ProTox II software. Promiscuous hits identified by the docking score and applying Lipinski's Rule of five were ZINC43200601, ZINC95593660 and ZINC95595125. These hits showed high binding scores and passed the colander of in silico pharmacokinetic and toxicity proving these ligands propitious to be further evaluated. For selecting the Activity Spectra for Substances PASS program was used to screen the anticancer potential of the compound. The hits displayed antitumor profile.

Luteolin is a common flavonoid that exists in many types of plants and exerts antioxidant and anti-inflammatory activity. Luteolin presents several hydroxyl groups, which limits their applications in some fields, due to their low solubility in lipophilic systems. To avoid that, luteolin can be acylated by lipase, using vinyl ester as acyl-donor. The aim of this study was the cytotoxicity evaluation of the non-modified luteolin and its comparison with the corresponding action of the reaction mixture after enzymatic modification with Thermomyces lanuginosus lipase (Luteolin-TLL) (3΄-O-acetyl luteolin and 4΄-O-acetyl luteolin), as well as the isolated fraction (3΄-O-acetyl luteolin). The NIH/3T3 fibroblasts were used for the in vitro experiments. Cytotoxicity was estimated by means of the MTT and clonogenic assay and flow cytometry was applied for the detection of Reactive Oxygen Forms (ROS) and cell cycle analysis. The compounds showed a dose- and time-dependent cytotoxic effect against NIH/3T3 cells. Long-term toxicities of luteolin and luteolin-TLL were higher than their short-term toxicities, while the isolated fraction with high short-term toxicity had lower long-term toxicity. Treatment with 10 μg/mL luteolin-TLL or the isolated product resulted in a mild increase in S-phase. On the contrary, luteolin arrested proliferating NIH/3T3 cells at Go/G1 phase. Luteolin-TLL and the isolated compound presented a greater ability to scavenge intracellular ROS. Enzymatic modification with TLL differentiated luteolin’s biological effects especially long-term cytotoxicity against the normal cells. Nonetheless, further molecular experiments will unfold more details about the compound’s mechanism of action.