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Cancer is one of the most deadly diseases worldwide, challenging the world for effective treatment of the diseases, to tackle this problem a vast amount of therapeutic candidates are being investigated. Indole-benzimidazole structures have recently gained considerable attention, because compounds containing these structure exhibit a very good anticancer property. Two series of novel indole-benzimidazole hybrids molecules viz., 2-(5-substituted-1H-indol-3-yl)-5-substituted-1H-benzo[d]imidazole 5(a-f) and 2-(5-substituted-1-(3-methylbut-2-enyl)-1H-indol-3-yl)-5-substituted-1H-benzo[d]imidazole 6(a-f) were synthesized and characterized by spectroscopic techniques. The twelve target molecules have been investigated for their in-vitro cytotoxic activity against human ovarian carcinoma cells (SKOV-3), human prostate cancer cells (PC-3), human cervical cancer cells (HeLa) and human acute monocytic leukemia cells (THP-1) using MTT assay. Compound; 2-(5-bromo-1H-indol-3-yl)-5-methyl-1H-benzo[d]imidazole (5e) was interesting with IC50 (μM) values of 23.69 (SKOV-3), 73.05 (PC-3), 64.66 (HeLa) and 39.08 (THP-1), respectively. KEY WORDS: Indole, Benzimidazole, Hybrid molecules, Anticancer activity Bull. Chem. Soc. Ethiop. 2023, 37(5), 1209-1220. DOI: https://dx.doi.org/10.4314/bcse.v37i5.13 &nbsp

Herein, we report the synthesis of four new hybrid molecules between ketoprofen or 2-(3-benzoylphenyl)propanoic acid and N-containing heterocyclic compounds, such as piperidine, pyrrolidine, 1,2,3,4-tetrahydroquinoline, and 1,2,3,4-tetrahydroisoquinoline. The obtained hybrid compounds were fully characterized using 1H- and 13C-NMR, UV-Vis, and HRMS spectra. Detailed HRMS analysis is provided for all novel hybrid molecules. The compounds were assessed for their in vitro anti-inflammatory and antioxidant activity. The lipophilicity of the hybrids was determined, both theoretically (cLogP) and experimentally (RM). The affinity of the compounds to the human serum albumin was assessed in silico by molecular docking study using two software, and the stability of the predicted complexes was evaluated by molecular dynamics study. All novel hybrids have shown very good HPSA activity, statistically close when compared to the reference—quercetin. The molecular docking confirmed the obtained in vitro results. Tetrahydroquinoline derivative 3c and tetrahydroisoquinoline derivative 3d have the highest affinity for albumin. They show stronger anti-inflammatory action than their predecessor, ketoprofen and the regularly used ibuprofen.

International audience; Among carbon-based materials, fullerenes have emerged as very fascinating nanocarbons on account of the interesting properties and applications of some of their derivatives in medicine or materials chemistry. The low solubility of C 60 , the most famous family member, has limited its use in medicinal chemistry but its covalent functionalization with different moieties such as porphyrins or other bioactive molecules changes its physicochemical properties, such as its solubility and biocompatibility. New hybrid compounds, bearing fullerene and steroid units in the same molecule can be regarded as promising functional chimeras with encouraging biomedical applications and have become a topic of considerable interest in the last few years. Recent developments in the syntheses of steroid-fullerene hybrids are described herein.

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the oldest and most widely used groups of drugs nowadays. However, the problem of searching for and creating new NSAIDs remains open, primarily due to the risks owing to their short- and long-term use. In this context, triazole-azepine hybrid molecules are attractive and prospective objects for the rational design of novel potential NSAIDs. In the present work studies of 3-aryl-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepines as potential non-steroidal anti-inflammatory agents are reported. Evaluation of drug-like properties for all tested triazole-azepine hybrids was performed in silico using SwissADME. The screening of analgesic and anti-inflammatory activities was performed in vivo using acid-induced writhing and carrageenin-induced hind paw oedema models in mice. Derivatives with activity levels more potent compared with reference drugs ketorolac and diclofenac sodium were identified. Preliminary SAR was performed based on the screening results.

The investigation of the reactivity of an α-amido sulfone derived from 2-formyl benzoate under organocatalytic conditions in the presence of acetylacetone allowed the synthesis of a new heterocyclic hybrid isoindolinone-pyrazole with high enantiomeric excess. Dibenzylamine was also used as a nucleophile to afford an isoindolinone with aminal substituent in 3-position in suitable selectivity. The use of Takemoto’s bifunctional organocatalyst not only led to observed enantioselectivity but was also important in accomplishing the cyclization step in both cases. Notably, this catalytic system proved to be particularly effective in comparison to widely used phase transfer catalysts.

The development of hybrid molecules with significant human therapeutic properties is one of the main approaches of pharmaceutical research. One of the most important pharmacophores is the quinazolin-4(3H)-one heterocycle moiety, due to its wide range of biological activities. By its derivatization with polyphenolic compounds, in our previous research, it proved to possess a good antiradical activity of ortho-diphenolic derivatives of quinazolin-4(3H)-one. In this study, we developed two new series of compounds, with an additional phenolic group or with a methyl group on the thioacetohydrazone fragment. The methods used to evaluate the activity of the compounds were radical scavenging, reduction of oxidizing reagents and transition metals’ ions chelation assays. Quantum descriptors were also calculated in order to evaluate the influence of substituents and their position on the activity of the compounds. The cytotoxic activity was evaluated using normal human foreskin fibroblast cells (BJ) and two cancerous cell lines, lung adenocarcinoma cells (A549) and prostate carcinoma cells (LNCaP). The results obtained for the pyrogallol derivatives showed a high antioxidant activity compared to ascorbic acid and Trolox. All the synthesized compounds displayed a higher cytotoxicity against the cancerous cell types and a high cytocompatibility with the normal cells. The antioxidant activity was deeply influenced by the addition of the third phenolic group in the synthesized molecules.

[Figure not available: see fulltext.] An atom-efficient method toward hybrid molecules via azide-alkyne cycloaddition of 7-azido-3-ethoxycarbonyl-1-ethyl-6-fluoroquinolin-4(1H)-one and novel perspective triazolopyrimidines has been developed. This procedure features mild conditions and a broad substrate scope including hydrophobic and hydrophilic triazolopyrimidines. The synthesized hybrid structures combine fragments of fluoroquinolone with proved antibacterial activity and triazolopyrimidines, which may act as structural analogs of adenosine receptor effectors or antiviral azoloazine heterocycles. © 2021, Springer Science+Business Media, LLC, part of Springer Nature. Russian Foundation for Basic Research, РФФИ: 18-03-00787 А We wish to thank the Russian Foundation for Basic Research for financial support (grant 18-03-00787 А).

Nineteen propylene tethered dihydroartemisinin-isatin hybrids 5a-g and 6a-l were designed, synthesized, and screened for their in vitro antiproliferative activity against three lung cancer cell lines, inclusive of drug-sensitive (A549), doxorubicin-resistant A549 (A549/DOX) and cisplatin-resistant A549 (A549/DDP) cell lines. The cytotoxicity of the synthesized hybrids towards normal lung epithelial cell line (BEAS-2B) was also assessed to evaluate the selectivity. The structure-activity relationship (SAR) elucidated that (1) alkyloxylimino fragment at C-3 position of isatin moiety were more favorable than the carbonyl and benzoxylimino, and the relative contricution order was methoxylimino > ethoxylimino > carbonyl > benzoxylimino; halogen atom at C-5 or C-6 position of isatin fragment could enhance the activity. Among them, hybrid 6f (IC50: 21.7–28.9 μM) showed promising activity against the three tested lung cancer cell lines, and the activity was not inferior to that of cisplatin (IC50: 19.7 and 66.9 μM) and doxorubicin (IC50: 54.3 and 15.1 μM) against multidrug-resistant A549/DOX and A549/DDP lung cancer cell lines. In addition, hybrid 6f (IC50: >100 μM) was non-cytotoxic towards normal lung epithelial cell line (BEAS-2B), and the RI values of hybrid 6f were 1.12 and 1.33. Further, hybrid 6f also possessed acceptable stability in mouse and human microsomes. Accordingly, hybrid 6a was a promising anti-lung cancer chemotherapeutic candidate and merited further evaluations.

Considering the important damage caused by the reactive oxygen (ROS) and nitrogen (RNS) species in the human organism, the need for new therapeutic agents, with superior efficacy to the known natural and synthetic antioxidants, is crucial. Quinazolin-4-ones are known for their wide range of biological activities, and phenolic compounds display an important antioxidant effect. Linking the two active pharmacophores may lead to an increase of the antioxidant activity. Therefore, we synthesized four series of new hybrid molecules bearing the quinazolin-4-one and phenol scaffolds. Their antioxidant potential was evaluated in vitro, considering different possible mechanisms of action: hydrogen atom transfer, ability to donate electrons and metal ions chelation. Theoretical quantum and thermodynamical calculations were also performed. Some compounds, especially the ortho diphenolic ones, exerted a stronger antioxidant effect than ascorbic acid and Trolox.

Fifteen dihydroartemisinin-isatin hybrids (5a-e and 6a-j) linked with three-carbon were designed, synthesized. The antiproliferative activity against lung cancer cell lines including drug-sensitive A549, doxorubicin-resistant A549 (A549/DOX) and cisplatin-resistant A549 (A549/DDP) lung cancer cell lines was tested. The cytotocivity towards normal lung epithelial BEAS-2B cell line was also investigated. From the structure-activity relationship (SAR), it was found that hydrogen bond donors (especially hydroxime and thiosemicarbazide) at C-3 position and electron-withdrawing groups (fluoro and chloro) at C-5 position of isatin moiety were beneficial for the activity. A significant part of them (half maximal inhibitory concentration/IC50: 5.72–55.52 μM) demonstrated considerable antiproliferative activity, and the activity was superior to that of dihydroartemisinin (IC50: 69.42–88.03 μM) and artemisinin (IC50: >100 μM). In particular, two hybrids 6a, e (IC50: 5.72–9.84 μM) were not inferior to doxorubicin (IC50: 4.06 μM) and cisplatin (IC50: 9.38 μM) against drug-sensitive A549 cells and were more potent than doxorubicin (IC50: 54.32 and 15.10 μM) and cisplatin (IC50: 19.74 and 66.89 μM) against multidrug-resistant A549/DOX and A549/DDP lung cancer cell lines. In addition, hybrids 6a, e (IC50: >100 μM) showed no toxicity towards BEAS-2B cells, proving their excellent selectivity profile. Furthermore, hybrid 6a also possessed good stability in mouse and human microsomes, as well as excellent pharmacokinetic properties. Accordingly, hybrid 6a could serve as a promising anti-lung cancer chemotherapeutic candidate for further preclinical evaluations.

Here we present design and synthesis of AT and TT harmiquins, evaluation of their biological activity and possible mechanism of action. Harmiquins displayed remarkable activity against the erythrocytic life stage of CQsensitive, as well as CQ-resistant Plasmodium strains. The most active compound, AT harmiquine 32, displayed a 5.5-fold higher activity against Pf3D7 than CQ (IC50 = 2 ± 0.3 nM), at least 15.9-fold higher activity than CQ against P. falciparum CQ resistant strains and had a very high selectivity index (4450). Two possible mechanisms of action, inhibition of heme polymerisation and binding to PfHsp90, might play a role in the inhibition of Plasmodium intraerythrocytic development.

The increasing urgency to feed the growing world population, along with growing consumer awareness and expectations, have driven the evolution of food production systems and the processes and products applied in the food industry. Although substantial progress has been made in food additives, the controversy in which some of them are still embroiled has encouraged research into the next safer and healthier generations. These additives can come from natural sources and confer health benefits, in addition to serving to color or preserve, among others.1 Limiting factors of these additives are often related to stability, sustainability, and cost-effectiveness issues, which justify the need for innovative solutions. Finding compounds that can have both capabilities (colorant and preservative) and additionally exert bioactive functions may be a promising solution. However, to obtain benefits such as antioxidant or antimicrobial activity, the concentrations of these compounds are often high, not meeting the acceptable daily intake (ADI) requirement. In addition, such compounds may take time to become part of the additives authorized for use by regulators, remembering that in addition to the research for these new molecules, they must undergo thorough toxicity and safety evaluation before their use is allowed for consumption.2 The research and development of new molecules through new chemical approaches, such as the modification of natural molecules already known and of accepted use worldwide, so that they can develop a better and double performance (colorant plus preservative), may be a path to be followed to circumvent the difficulties and monetize the use of these additive molecules in the food industry. Non-covalent complexation is a natural process and an important mechanism responsible for stabilizing and enhancing the blue, violet, and red colors in flowers, vegetables, and fruits, as well as in food products derived from them. The increased interest in copigmentation has been remarkable, especially by the food industry, in order to enhance the color palette. In view of its mastery and use through the selection of the better copigments to be added to food products, precise (computer-aided) control of the supramolecular assemblies of non-covalent supramolecular copigments is essential. In this regard, copigmentation with antioxidant/antimicrobial molecules can be explored, and the use of new cheminformatics tools and models can support the development of unique hybrid compounds with dual function (coloring and preserving), based on the screening of numerous biomolecules so as to spawn new bio-based molecules as the next generation of food additives.3 In this regard, and with the observed advances in computers and computational methodologies for in silico experimental aid, their exploitation for the research and development of these safer and more efficient bio-based hybrid molecules with dual functionality by predicting and verifying the experimental results, allow the study of certain physical characteristics that are not easily examined in the laboratory and are very promising, which can help and accelerate research on a topic that is now fundamental. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by F.C.T. and P.I., through the institutional scientific employment program-contract for C.P. and L.B. contracts and C.N. (2021.05369.BD) and A.K.M. (2020.06231.BD) PhD grants. To FEDER-Interreg España-Portugal programme for financial support through the project TRANSCoLAB 0612_TRANS_CO_LAB_2_P; to ERDF through the Regional Operational Program North 2020, within the scope of Project Mobilizador Norte-01-0247-FEDER-024479: ValorNatural®. The GIP-USAL is financially supported by the Spanish “Ministerio de Ciencia and Innovación” (PID2019-106167RB-I00) and “Junta de Castilla y León” (SA093P20 and CLU-2018-04). info:eu-repo/semantics/publishedVersion

In this study, novel hybrid isoindole-1,3(2H)-dione compounds (10 and 11) carrying a 1H-tetrazole moiety were synthesized, characterized and their inhibitory properties against xanthine oxidase (XO) and carbonic anhydrase isoenzymes (hCA I and hCA II) were investigated. Allopurinol for XO and acetazolamide for carbonic anhydrase isoenzymes were used as positive standards in inhibition studies. In addition, compounds 8 and 9, which were obtained in the intermediate step, were also investigated for their inhibition effects against the three enzymes. According to the enzyme inhibition results, hybrid isoindole-1,3(2H)-dione derivatives 10 and 11 showed significant inhibitory effects against all three enzymes. Surprisingly, compound 8, containing a SCN functional group, exhibited a greater inhibitory effect than the other compounds against hCA I and hCA II. The IC50 values of compound 8 against hCA I and hCA II were found to be 3.698 +/- 0.079 and 3.147 +/- 0.083 mu M, respectively. Compound 8 (IC50 = 4.261 +/- 0.034 mu M) showed higher activity than allopurinol (IC50 = 4.678 +/- 0.029 mu M) and the other compounds against XO, as well. These results clearly show the effect of the SCN group on the inhibition. In addition, in silico molecular docking studies were performed to understand the molecular interactions between each compound and enzymes, and the results were evaluated.

A series of 1,2,3-triazole tethered dihydroartemisinin-isatin hybrids 8a-c and 9a-k were designed and synthesized. Their antiproliferative activity against A549, doxorubicin-resistant A549 (A549/DOX) as well as cisplatin-resistant A549 (A549/DDP) lung cancer cell lines was also investigated in this study. All hybrids (half maximal inhibitory concentration/IC50: 7.54–73.8 μM) were more potent than the parent drug dihydroartemisinin (IC50: 69.4–88.0 μM) and also non-cytotoxic towards mouse embryonic fibroblast cells NIH/3T3 (IC50: >100 μM). The structure-activity relationships illustrated that the substituents on C-3 and C-5 position of isatin moiety influenced the activity significantly. Imine at C-3 position decreased the activity, whereas fluoro at C-5 position enhanced the activity. In particular, hybrids 8a,c (IC50: 7.54–12.1 μM) and 9i (IC50: 9.10–15.9 μM) were comparable to cisplatin (IC50: 7.54–15.9 μM vs 9.38–19.7 μM) against A549 and A549/DOX, but 4.6–7.6 folds more potent than that of cisplatin (IC50: 8.77–14.3 μM vs 66.9 μM) against A549/DDP cells. Moreover, hybrids 8a,c exhibited excellent stability (liver microsomes: 68–83%) in mouse/human microsomes and good pharmacokinetic properties, demonstrating their potential as a novel anti-lung cancer chemotherapeutic candidates.

Plants have been used by humans since ancient times due their antimicrobial and medicinal properties. Essential oils (EOs) are complex mixtures of secondary plant metabolites, including terpenoids, phenylpropanoids, and other aromatic compounds. Cinnamomun verum and Thyme vulgaris EOs and their organic extracts exert numerous biological activities because of their major compounds, particularly thymol, carvacrol, eugenol, and benzoic and cinnamic acid. The structural motifs presented by these phytochemicals are responsible for their biological activities. Modification or hybridization of these structures could lead to new bio-based compounds with improved efficacy or multiple modes of action. In this work, we aimed to develop reliable methods of obtaining six hybrid molecules from the major constituents of C. verum and T. vulgaris EOs. For the first time, we tested their efficacy in the inhibition of the mycelium growth and spore germination of two of the most important phytopathogenic fungi, Fusarium oxysporum and Colletotrichum gloeosporioides, and one opportunistic human pathogen, Aspergillus niger. The cytotoxic activity of the obtained hybrids was assessed using the brine shrimp lethality assay. In addition, we report for the first time a biocatalytic process for the obtention of these bioactive hybrid molecules. The results of this work enable the possibility of using hybrid molecules based on the major constituents of EOs as active ingredients in strategic industries such as agriculture, aquaculture, and pharmaceuticals.

Peptide–drug conjugates are delivery systems for selective delivery of cytotoxic agents to target cancer cells. In this work, the optimized synthesis of JH-VII-139-1 and its c(RGDyK) peptide conjugates is presented. The low nanomolar SRPK1 inhibitor, JH-VII-139-1, which is an analogue of Alectinib, was linked to the ανβ3 targeting oligopeptide c(RGDyK) through amide, carbamate and urea linkers. The chemostability, cytotoxic and antiangiogenic properties of the synthesized hybrids were thoroughly studied. All conjugates retained mid nanomolar-level inhibitory activity against SRPK1 kinase and two out of four conjugates, geo75 and geo77 exhibited antiproliferative effects with low micromolar IC50 values against HeLa, K562, MDA-MB231 and MCF7 cancer cells. The activities were strongly related to the stability of the linkers and the release of JH-VII-139-1. In vivo zebrafish screening assays demonstrated the ability of the synthesized conjugates to inhibit the length or width of intersegmental vessels (ISVs). Flow cytometry experiments were used to test the cellular uptake of a fluorescein tagged hybrid in MCF7 and MDA-MB231 cells that revealed a receptor-mediated endocytosis process. In conclusion, most conjugates retained the inhibitory potency against SRPK1 as JH-VII-139-1 and demonstrated antiproliferative and antiangiogenic activities. Further animal model experiments are needed to uncover the full potential of such peptide conjugates in cancer therapy and angiogenesis-related diseases.

International audience; Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen naturally resistant to many common antibiotics and acquires new resistance traits at an alarming pace. Targeting the bacterial virulence factors by an antivirulence strategy, therefore, represents a promising alternative approach besides antibiotic therapy. The Type III secretion system (T3SS) of P. aeruginosa is one of its main virulence factors. It consists of more than 20 proteins building a complex syringe-like machinery enabling the injection of toxin into host cells. Previous works showed that disrupting interactions between components of this machinery efficiently lowers the bacterial virulence. Using automated target-based screening of commercial and in-house libraries of small molecules, we identified compounds inhibiting the protein-protein interaction between PscE and PscG, the two cognate chaperones of the needle subunit PscF of P. aeruginosa T3SS. Two hits were selected and assembled using Split/Mix/Click chemistry to build larger hybrid analogues. Their efficacy and toxicity were evaluated using phenotypic analysis including automated microscopy and image analysis. Two nontoxic hybrid leads specifically inhibited the T3SS and reduced the ex vivo cytotoxicity of bacteria and their virulence in Galleria mellonella.

Chemotherapy is an important therapeutic approach for the treatment of cancer. Currently, many anticancer drugs are available in the market that plays an important role in cancer treatment, but concerns such as, drug resistance and side effects create an urgent need for the development of new anti-tumor drugs with high potency and less side effects. Heterocycles are of great interest due to their fascinating anticancer activity. Among them, 1,3,4-oxadiazoles showed attracting anti-tumor activity and its derivatives are under clinical trials for the treatment of cancer. Hybridization of 1,3,4-oxadiazole moiety with other heterocyclic pharmacophoresis a promising approach to overcome various disadvantages of current anticancer drugs such as drug resistance, toxicity, and other side effects. Thus, 1,3,4-oxadiazole-heterocycle hybrids occupy a significant position in the discovery of anti-tumor drugs. Among the reported oxadiazole-based hybrids reviewed here, compounds 45i, 59j, and 62x showed the highest anticancer activity with IC50 values in the nanomolar range. This review summarizes the recent developments in the anticancer potential, structure–activity relationships, and mechanisms of actions of 1,3,4-oxadiazole-heterocycle hybrids.

The median-effect principle proposed by Chou and Talalay is the most effective approach to parameterize interactions between several agents in combination. However, this method cannot be used to evaluate the effectiveness of equimolar drug combinations, which are comparative references for dual-targeting molecular design. Here, using data acquired through the development of “combi-molecules” blocking two kinases (e.g., EGFR-c-Src and EGFR-c-Met), we established potency indices for equimolar and dual-targeted inhibitors. If the fold difference (κ) between the IC50 of the two individual kinase inhibitors was &gt, 6, the IC50 of their equimolar combination resembled that of the more potent inhibitor. Hence, the “combi-targeting” of the two kinases was considered “imbalanced” and the combination ineffective. However, if κ ≤ 6, the IC50 of the combination fell below that of each individual drug and the combi-targeting was considered “balanced” and the combination effective. We also showed that combi-molecules should be compared with equimolar combinations only under balanced conditions and propose a new parameter Ω for validating their effectiveness. A multi-targeted drug is effective if Ω &lt, 1, where Ω is defined as the IC50 of the drug divided by that of the corresponding equimolar combination. Our study provides a methodology to determine the in vitro potency of equimolar two-drug combinations as well as combi-/hybrid molecules inhibiting two different kinase targets.

Lung cancer is the most common malignancy and leads to around one-quarter of all cancer deaths. Great advances have been achieved in the treatment of lung cancer with novel anticancer agents and improved technology. However, morbidity and mortality rates remain extremely high, calling for an urgent need to develop novel anti–lung cancer agents. 1,2,3-Triazole could be readily interact with diverse enzymes and receptors in organisms through weak interaction. 1,2,3-Triazole can not only be acted as a linker to tether different pharmacophores but also serve as a pharmacophore. This review aims to summarize the recent advances in 1,2,3-triazole–containing compounds with anti–lung cancer potential, and their structure–activity relationship (SAR) together with mechanisms of action is also discussed to pave the way for the further rational development of novel anti–lung cancer candidates.

We synthesized twelve hybrids based on curcumin and resveratrol, and their structures were elucidated by spectroscopic analysis. The chemopreventive potential of these compounds was evaluated against SW480 human colon adenocarcinoma cells, its metastatic derivative SW620, along with the non-malignant CHO-K1 cell line. Among the tested compounds, hybrids 3e and 3i (for SW480) and 3a, 3e and 3k (for SW620) displayed the best cytotoxic activity with IC50 values ranging from 11.52 ± 2.78 to 29.33 ± 4.73 µM for both cell lines, with selectivity indices (SI) higher than 1, after 48 h of treatment. Selectivity indices were even higher than those reported for the reference drug, 5-fluorouracil (SI = 0.96), the starting compound resveratrol (SI = 0.45) and the equimolar mixture of curcumin plus resveratrol (SI = 0.77). The previous hybrids showed good antiproliferative activity.

The androgen receptor inhibitor, Enzalutamide, proved effective against castration resistance prostate cancer, has demonstrated clinical benefits and increased survival rate in men. However, AR mutation (F876L) converts Enzalutamide from antagonist to agonist indicating a rapid evolution of resistance. Hence, our goal is to overcome this resistance mechanism by designing and developing novel Enzalutamide analogues. We designed a dataset of Enzalutamide derivatives using Enzalutamide's shape and electrostatic features to match with pharmacophoric features essential for tight binding with the androgen receptor. Based on this design strategy ten novel derivatives were selected including 5,5-dimethyl-3-(6-substituted benzo[d]thia/oxazol-2-yl)-2-thioxo-1-(4-(trifluoromethyl)pyridin-2-yl)imidazolidin-4-one (6a-j) for synthesis. All the compounds were evaluated in-vitro on prostate cancer cell lines DU-145, LNCaP and PC3. Interestingly, two compounds 3-(6-hydroxybenzo[d]thiazol-2-yl)-5,5-dimethyl-2-thioxo-1-(4-(trifluoromethyl)pyridin-2-yl) imidazolidin-4-one (6c, IC50 – 18.26 to 20.31μM) and 3-(6-hydroxybenzo[d]oxazol-2-yl)-5,5-dimethyl -2-thioxo- 1- (4-(trifluoromethyl) pyridin-2-yl)imidazolidin-4-one (6h, IC50 – 18.26 to 20.31μM) were successful with promising in-vitro antiproliferative activity against prostate cancer cell lines. The binding mechanism of potential androgen receptor inhibitors was further studied by molecular docking, molecular dynamics simulations and MM-GBSA binding free energy calculations and found in agreement with the in vitro studies. It provided strong theoretical support to our hypothesis., Hybrid molecules; Prostate cancer; Imidazolidinone derivatives; Molecular docking; Molecular dynamics simulations; Binding energy calculations.

In recent decades, molecular hybridization has proven to be an efficient tool for obtaining new synthetic molecules to treat different diseases. Based on the core idea of covalently combining at least two pharmacophore fragments present in different drugs and/or bioactive molecules, the new hybrids have shown advantages when compared with the compounds of origin. Hybridization could be successfully applied to anticancer drug discovery, where efforts are underway to develop novel therapeutics which are safer and more effective than those currently in use. Molecules presenting naphthoquinone moieties are involved in redox processes and in other molecular mechanisms affecting cancer cells. Naphthoquinones have been shown to inhibit cancer cell growth and are considered privileged structures and useful templates in the design of hybrids. The present work aims at summarizing the current knowledge on antitumor hybrids built using 1,4- and 1,2-naphthoquinone (present in natural compounds as lawsone, napabucasin, plumbagin, lapachol, α-lapachone, and β -lapachone), and the related quinolone- and isoquinolinedione scaffolds reported in the literature up to 2021. In detail, the design and synthetic approaches adopted to produce the reported compounds are highlighted, the structural fragments considered in hybridization and their biological activities are described, and the structure–activity relationships and the computational analyses applied are underlined.

In the present study, a focused combinatorial chemistry approach was applied to merge structural fragments of well-known TRPV1 antagonists with a potent anticonvulsant lead compound, KA-104, that was previously discovered by our group. Consequently, a series of 22 original compounds has been designed, synthesized, and characterized in the in vivo and in vitro assays. The obtained compounds showed robust in vivo antiseizure activity in the maximal electroshock (MES) test and in the 6 Hz seizure model (using both 32 and 44 mA current intensities). The most potent compounds 53 and 60 displayed the following pharmacological profile: ED50 = 89.7 mg/kg (MES), ED50 = 29.9 mg/kg (6 Hz, 32 mA), ED50 = 68.0 mg/kg (6 Hz, 44 mA), and ED50 = 73.6 mg/kg (MES), ED50 = 24.6 mg/kg (6 Hz, 32 mA), and ED50 = 56.3 mg/kg (6 Hz, 44 mA), respectively. Additionally, 53 and 60 were effective in the ivPTZ seizure threshold and had no influence on the grip strength and body temperature in mice. The in vitro binding and functional assays indicated a multimodal mechanism of action for 53 and 60. These molecules, beyond TRPV1 antagonism, inhibited calcium currents and fast sodium currents in patch-clamp assays. Further studies proved beneficial in vitro ADME-Tox properties for 53 and 60 (i.e., high metabolic stability, weak influence on CYPs, no neurotoxicity, etc.). Overall, 53 and 60 seem to be interesting candidates for future preclinical development in epilepsy and pain indications due to their interaction with the TRPV1 channel.

The evolution of peptidomimetic hybrid molecules for preoperative imaging and guided surgery targeting the prostate-specific membrane antigen (PSMA) significantly progressed over the past few years, and some approaches are currently being evaluated for further clinical translation. However, accumulation in nonmalignant tissue such as kidney, bladder, spleen, or liver might limit tumor-to-background contrast for precise lesion delineation, particularly in a surgical setting. To overcome these limitations, a rational linker design aims at the development of a second generation of PSMA-11-based hybrid molecules with an enhanced pharmacokinetic profile and improved imaging contrast. Methods: A selection of rationally designed linkers was introduced to the PSMA-targeting hybrid molecule Glu-urea-Lys-HBED-CC-IRDye800CW, resulting in a second-generation peptidomimetic hybrid molecule library. The biologic properties were investigated in cell-based assays. In a preclinical proof-of-concept study with the radionuclide 68Ga, the impact of the modifications was evaluated by determination of specific tumor uptake, pharmacokinetics, and fluorescence imaging in tumor-bearing mice. Results: The modified hybrid molecules carrying various selected linkers revealed high PSMA-specific binding affinity and effective internalization. The highest tumor-to-background contrast of all modifications investigated was identified for the introduction of a histidine- (H) and glutamic acid (E)-containing linker ((HE)3-linker) between the PSMA-binding motif and the chelator. In comparison to the parental core structure, uptake in nonmalignant tissue was significantly reduced to a minimum, as exemplified by an 11-fold reduced spleen uptake from 38.12 ± 14.62 percentage injected dose (%ID)/g to 3.47 ± 1.39 %ID/g (1 h after injection). The specific tumor uptake of this compound (7.59 ± 0.95 %ID/g, 1 h after injection) was detected to be significantly higher than that of the parental tracer PSMA-11. These findings confirmed by PET and fluorescence imaging are accompanied by an enhanced pharmacokinetic profile with accelerated background clearance at early time points after injection. Conclusion: The novel generation of PSMA-targeting hybrid molecules reveals fast elimination, reduced background organ enrichment, and high PSMA-specific tumor uptake meeting the key demands for potent tracers in nuclear medicine and fluorescence-guided surgery. The approach's efficacy in improving the pharmacokinetic profile highlights the strengths of rational linker design as a powerful tool in strategic hybrid-molecule development.

Malaria is among the deadliest infectious diseases in the world caused by Plasmodium parasites. Due to the high complexity of the parasite’s life cycle, we partly depend on antimalarial drugs to fight this disease. However, the emergence of resistance, mainly by Plasmodium falciparum, has dethroned most of the antimalarials developed to date. Given recent reports of resistance to artemisinin combination therapies, first-line treatment currently recommended by the World Health Organization, in Western Cambodia and across the Greater Mekong sub-region, it seems very likely that artemisinin and its derivatives will follow the same path of other antimalarial drugs. Consequently, novel, safe and efficient antimalarial drugs are urgently needed. One fast and low-cost strategy to accelerate antimalarial development is by recycling classical pharmacophores. Quinacrine, an acridine-based compound and the first clinically tested synthetic antimalarial drug with potent blood schizonticide but serious side effects, has attracted attention due to its broad spectrum of biological activity. In this sense, the present review will focus on efforts made in the last 20 years for the development of more efficient, safer and affordable antimalarial compounds, through recycling the classical quinacrine drug.

Epilepsy belongs to the most common and debilitating neurological disorders with multifactorial pathophysiology and a high level of drug resistance. Therefore, with the aim of searching for new, more effective, and/or safer therapeutics, we discovered a focused series of original hybrid pyrrolidine-2,5-dione derivatives with potent anticonvulsant properties. We applied an optimized coupling reaction yielding several hybrid compounds that showed broad-spectrum activity in widely accepted animal seizure models, namely, the maximal electroshock (MES) test and the psychomotor 6 Hz (32 mA) seizure model in mice. The most potent anticonvulsant activity and favorable safety profile was demonstrated for compound 30 (median effective dose (ED50) MES = 45.6 mg/kg, ED50 6 Hz (32 mA) = 39.5 mg/kg, median toxic dose (TD50) (rotarod test) = 162.4 mg/kg). Anticonvulsant drugs often show activity in pain models, and compound 30 was also proven effective in the formalin test of tonic pain, the capsaicin-induced pain model, and the oxaliplatin (OXPT)-induced neuropathic pain model in mice. Our studies showed that the most plausible mechanism of action of 30 involves inhibition of calcium currents mediated by Cav1.2 (L-type) channels. Importantly, 30 revealed high metabolic stability on human liver microsomes, negligible hepatotoxicity, and relatively weak inhibition of CYP3A4, CYP2D6, and CYP2C9 isoforms of cytochrome P450, compared to reference compounds. The promising in vivo activity profile and drug-like properties of compound 30 make it an interesting candidate for further preclinical development.

Carbon monoxide (CO) produced by heme oxygenase-1 (HO-1) or delivered by CO-releasing molecules (CO-RMs) exerts anti-inflammatory action, a feature also exhibited by the nuclear factor erythroid 2-related factor 2 (Nrf2), a master regulator of the stress response. We have recently developed new hybrid molecules (HYCOs) consisting of CO-RMs conjugated to fumaric esters known to activate Nrf2/HO-1. Here we evaluated the biological activities of manganese (Mn) and ruthenium (Ru)-based HYCOs in human monocytes and keratinocytes in vitro as well as in vivo models of inflammation. The effects of HYCOs were compared to: a) dimethyl fumarate (DMF), a known fumaric ester used in the clinic; b) a CO-RM alone; or c) the combination of the two compounds. Mn–HYCOs donated CO and up-regulated Nrf2/HO-1 in vitro more efficiently than Ru–HYCOs. However, irrespective of the metal, a strong reduction in anti-inflammatory markers in monocytes stimulated by LPS was observed with specific HYCOs. This effect was not observed with DMF, CO-RM alone or the combination of the two, indicating the enhanced potency of HYCOs compared to the separate entities. Selected HYCOs given orally to mice accelerated skin wound closure, reduced psoriasis-mediated inflammation and disease symptoms equalling or surpassing the effect of DMF, and ameliorated motor dysfunction in a mouse model of multiple sclerosis. Thus, HYCOs have potent anti-inflammatory activities that are recapitulated in disease models in which inflammation is a prominent component. Prolonged daily administration of HYCOs (up to 40 days) is well tolerated in animals. Our results clearly confirm that HYCOs possess a dual mode of action highlighting the notion that simultaneous Nrf2 targeting and CO delivery could be a clinically relevant application to combat inflammation., Graphical abstract Image 1, Highlights • HYCOs are dual activity molecules targeting the Nrf2/HO-1 axis and delivering carbon monoxide. • Mn- and Ru-based HYCOs were compared in in vitro and in vivo models of inflammation. • HYCOs reduce inflammation in monocytes and increase proliferation in keratinocytes. • Oral administration of HYCOs accelerates skin wound healing and ameliorates psoriasis and multiple sclerosis.

The research explores the synthesis of a series of novel hybrid quinazolin-2,4-dione analogs bearing acetyl/amide bridged-nitrogen heterocyclic moieties such as azetidinone, pyrrole, oxazole, oxadiazole, thiazole, pyrazole, and thiazolidine scaffolds 2-16. The newly synthesized compounds were structurally confirmed by means of IR, 1H-NMR, 13C-NMR, MS and elemental analysis. In addition, an in silico molecular docking analysis of new compounds and standard drug (Chloroquine) has been performed to analyze the binding modes of interaction to the putative active site of Plasmodium falciparum Dihydroorotate dehydrogenase (pfDHODH). Aiming to search for potentially better antimalarials, a modern approach has been undertaken to identify new quinazolin-2,4-dione derivatives targeting pfDHODH. The identification of antimalarial activity of the newly synthesized compounds by using experimental techniques is expensive and requires extensive pains and labor. The compound 11 showed the highest binding affinity against pfDHODH. Moreover, the electrostatic potential (ESP) of the docked molecules was also calculated. Further, the pharmacokinetic properties (ADMET) of the prepared compounds were predicted through in silico technique.

Different hybrids based on curcumin and resveratrol were previously synthesized and characterized by spectroscopic techniques. The most active molecules (3a, 3e, 3i, and 3k) were evaluated in vitro as an approach to determine the possible mechanism of action of the hybrids. The results indicated that the evaluated curcumin/resveratrol hybrids induce mitochondrial instability in SW620 and SW480 cells. Moreover, these molecules caused a loss in membrane integrity, suggesting an apoptotic process mediated by caspases after the treatment with compounds 3i (SW480) and 3k (SW620). In addition, the results suggest that the mechanism of action of the hybrids could be independent of the p53 status. Furthermore, hybrids 3e and 3i caused G0/G1 phase arrest, which highlights the potential of these molecules not only as cytotoxic but also as cytostatic compounds. Hybrids 3e and 3i caused a negative modulation of the matrix metalloproteinase 7 (MMP7) on SW480 cells. These curcumin resveratrol hybrids could be potential candidates for further investigations in the search for potential chemopreventive agents, even in those cases with resistance to conventional chemotherapy because of the lack of p53 expression or function. Molecular docking simulations showed that compounds 3e, 3i, and 3k bind efficiently to proapoptotic human caspases 3/7 proteins, as well as human MMP-7 and p53, which, in turn, could explain at the molecular level the in vitro cytotoxic effect of these compounds in SW480 and SW620 colon cancer cell lines.

Background/Aims: Bone metastasis of cancer cells decreases patient survival and quality of life. Hybridization via the covalent coupling of two bioactive natural products is a useful strategy for developing more potent anticancer agents by enhancing their bioavailability and avoiding drug resistance. Methods: The in vivo activities of artemisinin-daumone hybrid 15 (ARTD) were estimated in cancer cell-inoculated mice and ovariectomized mice. The viability, migration, and invasion of cancer cells were measured via MTT, wound-healing, and transwell invasion assays. ARTD-regulated transcription factors were detected with an RT2 profiler PCR array kit and Western blotting. Osteoclastogenesis and osteoclast activity were detected with tartrate-resistant acid phosphatase staining, a pit formation assay, gelatin zymography, and a cathepsin K ELISA assay. Results: ARTD blocked cancer-associated osteolysis more potently than artemisinin in mice with intratibially inoculated breast cancer or lung cancer cells. ARTD inhibited the viability, migration, and invasion of breast and lung cancer cells in the absence or presence of transforming growth factor-β1. ARTD treatment induced the expression of tumor suppressive activating transcription factor 3 and inhibited oncogenic E2F transcription factor 1 expression at the mRNA and protein levels. ARTD inhibited receptor activator of nuclear factor kappa-B ligand-induced osteoclast formation and bone resorbing activity by reducing the secreted levels of matrix metalloproteinase-9 and cathepsin K. Furthermore, ARTD prevented estrogen deficiency-induced bone loss in ovariectomized mice. Conclusion: ARTD may be a promising candidate for inhibiting cancer-induced bone destruction. The application of ARTD may be extended to patients with chemotherapy-induced ovarian failure or postmenopausal osteoporosis.

The development of PSMA-targeting low-molecular-weight hybrid molecules aims at advancing preoperative imaging and accurate intraoperative fluorescence guidance for improved diagnosis and therapy of prostate cancer. In hybrid probe design, the major challenge is the introduction of a bulky dye to peptidomimetic core structures without affecting tumor-targeting properties and pharmacokinetic profiles. This study developed a novel class of PSMA-targeting hybrid molecules based on the clinically established theranostic agent PSMA-617. The fluorescent dye-bearing candidates of the strategically designed molecule library were evaluated in in vitro assays based on their PSMA-binding affinity and internalization properties to identify the most favorable hybrid molecule composition for the installation of a bulky dye. The library’s best candidate was realized with IRDye800CW providing the lead compound. Glu-urea-Lys-2-Nal-Chx-Lys(IRDye800CW)-DOTA (PSMA-927) was investigated in an in vivo proof-of-concept study, with compelling performance in organ distribution studies, PET/MRI and optical imaging, and with a strong PSMA-specific tumor uptake comparable to that of PSMA-617. This study provides valuable insights about the design of PSMA-targeting low-molecular-weight hybrid molecules, which enable further advances in the field of peptidomimetic hybrid molecule development.

An easy access to hybrid bioactive molecules, such as the chromenopyrazoles, is described based on the three-component reactions of 3-formylchromones, arylhydrazines, and acetylenedicarboxylates. By manipulating the reaction, four different scaffolds can be derived in an easy, versatile, and robust fashion. To underscore the potential, generality, and diversity that can be generated, representative libraries of each scaffold were synthesized. Moreover, a comprehensive NMR analysis with full assignment of all 1H and 13C NMR chemical shifts has been performed.

Traditional chemotherapy relies on the premise that rapidly proliferating cancer cells are more likely to be killed by a cytotoxic agent, but in reality, the long-standing problem of chemotherapy is the lack of tumor-specific treatments. Apart from the impact on tumor cells, the drugs' major limitation is their severe adverse side effects on normal cells and tissues. Nutritional and epidemiological studies have indicated that cancer progression is correlated with the consumption of fatty acids, but the exact mechanisms still remain unknown. In the first part of our review, we discussed the beneficial effects of free fatty acids (saturated and unsaturated) on the progress of carcinogenesis in different tumor cell lines. We presented various mechanisms proposed in the literature, which explain the possible impact on the cells metabolism. The second part describes modifications of different fatty acids with existing anticancer drugs and heterocyclic moieties by condensation reactions. Such conjugations increased the tissue selectivity and made chemotherapy potentially more effective and less toxic in in vivo and in vitro studies. This fatty acid modifications, which change the activity of compounds, their uptake selectivity and alter drug delivery methods, may be the key to unlocking true medical potential of fatty acids.

International audience; The emergence of Plasmodium falciparum parasites, responsible for malaria disease, resistant to antiplasmodial drugs including the artemisinins, represents a major threat to public health. Therefore, the development of new antimalarial drugs or combinations is urgently required. In this context, several hybrid molecules combining a dihydroartemisinin derivative and gold(I) N-heterocyclic carbene (NHC) complexes have been synthesized based on the different modes of action of the two compounds. The antiplasmodial activity of these molecules was assessed in vitro as well as their cytotoxicity against mammalian cells. All the hybrid molecules tested showed efficacy against P. falciparum, in a nanomolar range for the most active, associated with a low cytotoxicity. However, cross-resistance between artemisinin and these hybrid molecules was evidenced. These results underline a fear about the risk of cross-resistance between artemisinins and new antimalarial drugs based on an endoperoxide part. This study thus raises concerns about the use of such molecules in future therapeutic malaria policies.

Although the wide arsenal of drugs available to treat bacterial infections, emerging drug-resistant bacterial pathogens have recently highlighted an urgent need to find new more effective and less toxic therapeutic agents. Fluoroquinolones, including norfloxacin, are antibiotics showing a concentration-dependent bactericidal capacity due to the activity inhibition of DNA-gyrase and topoisomerase IV, which are enzymes essential for bacterial DNA replication. Naphthoquinones are secondary metabolites showing different biological activities, including cytotoxic, antibacterial and antifungal effects. In particular, the efficacy of natural and synthetic 1,4-naphthoquinone derivatives is likely due to their oxidizing/reducing capability, through which they destroy cellular targets as nucleic acids. Hybrid molecules are produced combining structural features of two or more bioactive compounds, in order to obtain new therapeutic agents able, not only to reduce undesirable side effects of the parent drugs, but also to inhibit more biological targets, hopefully with a better therapeutic property than the administration of combined single-target drugs. With the aim to apply this strategy in the study of new potential antimicrobial agents, we have synthesized four hybrid molecules by the reaction of norfloxacin with suitable quinones and their activities have been evaluated against both bacteria and fungi, in comparison with synthetic precursors. The experimental data are supported by docking calculations on S. aureus DNA-gyrase, discussing the interactions involved for each hybrid molecule, in comparison with norfloxacin and the original ligand moxifloxacin.

A set of methylimidazolium-furanchalcone hybrids and 1-alkyl-3-methylimidazolium salts were tested in order to find their antimicrobial activity against five gram positive bacteria, two gram negative bacteria and three fungi. In the series of 1-alkyl-3-methylimidazolium salts, compounds 4 and 7 were the most active compounds against S. mutans and F. oxysporum, respectively (MIC value of 3.0 and 6.7 mM, respectively). In addition, among the hybrid molecules, compound 10 exhibited the highest activity against F. solani (MIC50 = 14.3 mM) followed by hybrid 11 (MIC50 = 14.5 mM), which was also the most active against S. aureus, S. mutans (MIC50 = 14.6, 18.7 mM, respectively). The activity of these hybrids was even better with regard to the lead compounds (furanchalcone, methylimidazole or the mixture). In the structure-activity relationship there was observed higher bioactivity when the alkyl linker had eigth carbon atoms. This was then supported by the in silico study which displayed a strong relationship between the length of the alkyl chain on N and the biological activity. The results highlight the importance of these derivatives (1-alkyl-3-methylimidazolium salts) and hybrids (methylimidazolium-furanchalcone) as potential antimicrobial agents.

International audience; Glioblastoma is the most common cerebral tumor in adults. The median survival of glioblastoma patients is 12 months. Metformin is a biguanide used as a standard clinical drug for the treatment of type 2 diabetes. Recently, several studies revealed that the risk of cancer development was significantly reduced for diabetic patients treated with metformin compared to those treated with insulin or sulfonylureas [1]. Even if metformin acts as an antitumoral agent, it is a nontoxic molecule with IC50 around 10 mM in cancer cells. In cancer research, naturally occurring phenolic acids are well known to be useful antioxidant agents and allow the inhibition of the migration and adhesion of cancer cells [2]. Moreover, a recent study [3] on nitrones combined with phenolic acids has shown that phenolic acids keep their antioxidant properties even if they are coupled with another molecule. The purpose of this study is to design new molecules combining metformin and a phenolic acid to improve the cytotoxicity on cancer cells. A series of hybrid molecules was then synthesized. For each molecule, IC50 on glioblastoma cell lines (U87 and U251) and on human dermal fibroblasts was tested. After this first screening, the mechanisms through which the best hybrid molecules act on cancer cells were studied and compared with those of metformin. Finally, the study of cytotoxicity on cancer stems cells of glioblastoma, GBM6, and GBM9 revealed that metformin-derived molecules may also restrict the growth of stem cells. As cancer stem cells are one of the causes of tumor resistance [4], metformin hybrid molecules may become a novel therapeutic option to treat glioblastoma. References 1. Zi, F.; Zi, H.; Li, Y.; He, J.; Shi, Q.; Cai, Z. Metformin and cancer: An existing drug for cancer prevention and therapy. Oncology Lett. 2018, 15, 683-690. 2. Bouzaiene, N.N.; Jaziri, S.K.; Kovacic, H.; Chekir-Ghedira, L.; Ghedira, K.; Luis, J. The effects of caffeic, coumaric and ferulic acids on proliferation, superoxide production, adhesion and migration of human tumor cells in vitro. Eur. J. Pharmacol. 2015, 766, 99-105. 3. Cassien, M.; Petrocchi, C.; Thétiot-Laurent, S.; Robin, M.; Ricquebourg, E.; Kandouli, C.; Asteian, A.; Rockenbauer A.; Mercier, A.; Culcasi, M.; et al. On the vasoprotective mechanisms underlying novel β-phosphorylated nitrones: Focus on free radical characterization, scavenging and NO-donation in a biological model of oxidative stress. Eur. J. Med. Chem. 2016, 119, 197-217.

Molecular hybridization has proven to be a successful multi-target strategy in the design and development of new antitumor agents. Based on this rational approach, we have planned hybrid molecules containing covalently linked pharmacophoric units, present individually in compounds acting as inhibitors of the cancer protein targets tubulin, human topoisomerase II and ROCK1. Seven new molecules, selected by docking calculation of the complexes with each of the proteins taken into consideration, have been efficiently synthesized starting from 2,3-dichloro-1,4-naphtoquinone or 6,7-dichloro-5,8-quinolinquinone. By screening the full National Cancer Institute (NCI) panel, including 60 human cancer cell lines, four molecules displayed good and sometimes better growth inhibition GI50 than the ROCK inhibitor Y-27632, the Topo II inhibitor podophyllotoxin and the tubulin inhibitor combretastatin A-4. The relative position of N,N heteroatoms in the structures of the tested compounds was crucial in affecting bioactivity and selectivity. Furthermore, compound 3 (2-(4-(2-hydroxyethyl)piperazin-1-yl)-3-(3,4,5-trimethoxyphenoxy)naphthalene-1,4-dione) emerged as the most active in the series, showing a potent and selective inhibition of breast cancer BT-549 cells (GI50 &lt, 10 nM).

The small pyrazolone-bearing molecules attract attention and are widely explored in drug design as pharmacological agents. The new pyrazolone-thiadiazole hybrid molecule N-(3-cyano-4,5,6,7-tetrahydrobenzothiophen-2-yl)-2-[[5-[(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)amino]-1,3,4-thiadiazol-2-yl]sulfanyl]acetamide (3) has been synthesized following a two-stage protocol using simple, convenient transformations and cheap, commercially available reagents. The compound’s structure was confirmed using 1H, 13C nuclear magnetic resonance (NMR), and liquid chromatography–mass spectrometry (LC–MS) spectra. The anti-inflammatory potency of 3 was evaluated in silico using molecular docking. The docking studies results suggest that title compound 3 is of great interest for further structure optimization and in-depth studies as a possible 5-lipoxygenase (5-LOX) inhibitor.

A series of 2-imino-2H-chromen-3-yl-1,3,5-triazine compounds 5&ndash, 12, which are namely hybrids of 2,4-diamino-1,3,5-triazines and 2-imino-coumarins, was synthesized by reacting 2-(4,6-diamine-1,3,5-triazin-2-yl)acetonitriles 1&ndash, 4 with 2-hydroxybenzaldehydes. After this, upon heating in aqueous DMF, 2-imino-2H-chromen-3-yl-1,3,5-triazines 10 and 12 were converted into the corresponding 2H-chromen-3-yl-1,3,5-triazines 13 and 14, which are essentially hybrids of 2,4-diamino-1,3,5-triazines and coumarins. The in vitro anticancer activity of the newly prepared compounds was evaluated against five human cancer cell lines: DAN-G, A-427, LCLC-103H, SISO and RT-4. The greatest cytotoxic activity displayed 4-[7-(diethylamino)-2-imino-2H-chromen-3-yl]-6-(4-phenylpiperazin-1-yl)-1,3,5-triazin-2-amine (11, IC50 in the range of 1.51&ndash, 2.60 &mu, M).

Naturally occurring terpenes were combined by click reactions to generate sixteen hybrid molecules. The diterpene imbricatolic acid (IA) containing an azide group was used as starting compound for the synthesis of all the derivatives. The alkyne group in the terpenes cyperenoic acid, dehydroabietinol, carnosic acid &gamma, lactone, ferruginol, oleanolic acid and aleuritolic acid was obtained by esterification using appropriate alcohols or acids. The hybrid compounds were prepared by combining the IA azide function with the different terpene-alkynes under click chemistry conditions. The cytotoxic activity of the terpene hybrids 1&ndash, 16 was assessed against Vero cells and tumour cell lines (HEP-2, C6 and Raw 264.7). Compounds 1, 2, 3 and 7 showed cytotoxic activity against the tested cell lines. The antiviral activity of the compounds was evaluated against HSV-1 KOS, Field and B2006 strain. For the pairs of hybrid compounds formed between IA-diterpene (compounds 3&ndash, 8, except for compound 7), a moderate activity was observed against the three HSV-1 strains with an interesting selectivity index (SI &ge, 10, SI = CC50/CE50) for some compounds.

The cholinergic hypothesis has been reported first being the cause of memory dysfunction in the Alzheimer’s disease. Researchers around the globe have focused their attention on understanding the mechanisms of how this complicated system contributes to processes such as learning, memory, disorientation, linguistic problems, and behavioral issues in the indicated chronic neurodegenerative disease. The present review reports recent updates in hybrid molecule design as a strategy for selectively addressing multiple target proteins involved in Alzheimer’s disease (AD) and the study of their therapeutic relevance. The rationale and the design of the bifunctional compounds will be discussed in order to understand their potential as tools to investigate the role of the cholinergic system in AD.

The discovery of new and more potent antitumor molecules that act simultaneously on multiple targets is one of the most active fields of research in chemotherapy. The use of methodologies based on cheminformatics, including Quantitative- Structure–Activity Relationship (QSAR) techniques play important role in pharmaceutical design of more efficient antitumor drugs. Also, QSAR analysis is a practical tool for prediction of antitumor activity of new and untested antioxidant. New hybrid molecules with 7- chloroquinoline and arylamidine moieties have been the most effective compounds against leukemia cell lines (K562 and Raji). Antitumor activity was modelled using mono-dimensional (1D), to three- dimensional molecular (3D) descriptors. In order to find a thriving QSAR models for antitumor activities, genetic algorithm- multilinear regression (GA-MLR) was used. The best obtained QSAR models include the following group of descriptors: RDF (Radial Distribution Function) ; GETAWAY (Geometry, Topology, and Atom-Weights AssemblY) descriptors, electronic charge, and information indices. Obtained QSAR models relieved in elucidation of important physicochemical and structural requirements for this biological activity. Highly potent molecules should have increased: three- dimensional distribution of mass in molecules calculated at the radius of 110 Å, atomic distribution at neighbourhood symmetry of 1- order, electric dipole moment along X-axis, as well as more atoms higher electronegativity distributed at the topological distance 3. Based on the conclusions given in the QSAR analysis, a new compounds with possible great antitumor activity were proposed and predicted by means of obtained QSAR models, giving a guidance for further synthesis of new effective quinoline- arylamidine hybrid molecules.

Recently, we have synthesized and evaluated antitumor activity of a new class of hybrid molecules joining these two pharmacophores: 7- chloroquinoline and arylamidine (CQArA). (Krstulović et al., 2017). UV/Vis titrations of compounds with ds-polynucleotides suggested DNA/RNA groove binding as the dominant binding mode. Molecular docking techniques provide to understand the drug–DNA interactions in rational drug design, as well as in the mechanistic study by placing a small molecule into the binding site. In order to elucidate the binding mode between CQArA hybrids and B- DNA (d(CGCGAATTCGCG)2) (PDB: ID: 1BNA), molecular docking was performed. The Hex 8.0 performs docking using Spherical Polar Fourier Correlations. Binding energies of the two best most effective compounds against leukemia cell lines (K562 and Raji), and two new highly potent quinolone-arylamidine analogues proposed according the quantitative structure-activity relationship (QSAR) predictive model for antitumor activity. Compounds were ranked by combining the pharmacological interactions and energy-based scoring function or total energy (Etotal). Molecular docking confirmed that compounds bound preferentially in the DNA grooves. Also, antiproliferative effects can be improved with the extension of the molecules' central linker. This extension enhances the flexibility and adaptability of the molecular conformation, causing variations in the DNA binding mode. This study provide a deeper insight of interactions of CQArA hybrids with DNA. [1] L. Krstulović, I. Stolić, Jukić M., Opačak-Bernardi T., Starčević K., Bajić M., Glavaš- Obrovac Lj. Eur. J. Med. Chem. 17 (2017) 196.

H2S is a gaseous molecule able to trigger a plethora of central physiological and pharmacological effects as antioxidant, pro- and anti-inflammatory, pro- and anti-nociceptive, neuromodulator, and cytoprotective. The polypharmacology of H2S depends on the wide variety of targets implicated, but, despite the efforts, the mechanisms of action that should clarify its activity are still not completely unrevealed. Nevertheless, many attempts to exploit the multifaceted profile of this molecule have already been accomplished and many chemical entities containing an H2S-releasing pharmacophore have been synthetized. Here we discuss recent investigations on multitarget molecules able to release H2S, with a particular focus on the combinations of “native drug” with moieties structurally able to release H2S and their applications as therapeutic tools in bone disease, gastrointestinal system and neurodegenerative disorders.

Cancer is a multifactorial disease that requires treatments able to target multiple intracellular components and signaling pathways. The natural compound, curcumin, was already described as a promising anticancer agent due to its multipotent properties and huge amount of molecular targets in vitro. Its translation to the clinic is, however, limited by its reduced solubility and bioavailability in patients. In order to overcome these pharmacokinetic deficits of curcumin, several strategies, such as the design of synthetic analogs, the combination with specific adjuvants or nano-formulations, have been developed. By taking into account the risk-benefit profile of drug combinations, as well as the knowledge about curcumin's structure-activity relationship, a new concept for the combination of curcumin with scaffolds from different natural products or components has emerged. The concept of a hybrid curcumin molecule is based on the incorporation or combination of curcumin with specific antibodies, adjuvants or other natural products already used or not in conventional chemotherapy, in one single molecule. The high diversity of such conjugations enhances the selectivity and inherent biological activities and properties, as well as the efficacy of the parental compound, with particular emphasis on improving the efficacy of curcumin for future clinical treatments.

The lack of an adequate therapy for Alzheimer's Disease (AD) contributes greatly to the continuous growing amount of papers and reviews, reflecting the important efforts made by scientists in this field. It is well known that AD is the most common cause of dementia, and up-to-date there is no prevention therapy and no cure for the disease, which contrasts with the enormous efforts put on the task. On the other hand many aspects of AD are currently debated or even unknown. This review offers a view of the current state of knowledge about AD which includes more relevant findings and processes that take part in the disease; it also shows more relevant past, present and future research on therapeutic drugs taking into account the new paradigm “Multi-Target-Directed Ligands” (MTDLs). In our opinion, this paradigm will lead from now on the research toward the discovery of better therapeutic solutions, not only in the case of AD but also in other complex diseases. This review highlights the strategies followed by now, and focuses other emerging targets that should be taken into account for the future development of new MTDLs. Thus, the path followed in this review goes from the pathology and the processes involved in AD to the strategies to consider in on-going and future researches.

One of the most viable options to tackle the growing resistance to the antimalarial drugs such as artemisinin is to resort to synthetic drugs. The multi-target strategy involving the use of hybrid drugs has shown promise. In line with this, new hybrids of quinoline with pyrimidine have been synthesized and evaluated for their antiplasmodial activity against both CQS and CQR strains of Plasmodium falciparum. These depicted activity in nanomolar range and were found to bind to heme as well as AT rich pUC18 DNA., Graphical abstract Efficaciously synthesized new 4-aminoquinoline–pyrimidine hybrids depict antiplasmodial activity (nM) against CQR and CQS strains of Plasmidum falciparum. Representative compounds revealed binding with heme and AT rich pUC18 DNA, spectrophotometically., Highlights • New hybrids of 4-aminoquinoline and pyrimidine were synthesized efficaciously. • nM range antiplasmodial activity. • Activity against both CQS and CQR strains of Plasmodium falciparum. • Effective binding to heme as well as AT rich pUC18 DNA.

This Special Issue, entitled “Molecules against Alzheimer”, gathers a number of original articles, short communications, and review articles on recent research efforts toward the development of novel drug candidates, diagnostic agents and therapeutic approaches for Alzheimer’s disease (AD), the most prevalent neurodegenerative disorder and a leading cause of death worldwide. This Special Issue contains many interesting examples describing the design, synthesis, and pharmacological profiling of novel compounds that hit one or several key biological targets, such as cholinesterases, β-amyloid formation or aggregation, monoamine oxidase B, oxidative stress, biometal dyshomeostasis, mitochondrial dysfunction, serotonin and/or melatonin systems, the Wnt/β-catenin pathway, sigma receptors, nicotinamide phosphoribosyltransferase, or nuclear erythroid 2-related factor. The development of novel AD diagnostic agents based on tau protein imaging and the use of lithium or intranasal insulin for the prevention or the symptomatic treatment of AD is also covered in some articles of the Special Issue.