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Quinolinotriazole antiplasmodials via click chemistry: synthesis and in vitro studies of 7-Chloroquinoline-based compounds

Abstract

Malaria is nowadays one of the most serious health concerns in a global scale and, although there is an evident increase in research studies in this area, pointed by the vast number of hits and leads, it still appears as a recurrent topic every year due to the drug resistance shown by the parasite exposing the urgent need to develop new antimalarial medications. In this work, 38 molecules were synthesized via copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) or “click” chemistry, following different routes to produce 2 different organic azides, obtained from a 4,7 dicholoquinoline, reacted with 19 different commercially available terminal alkynes. All those new compounds were evaluated for their in vitro activity against the chloroquine resistant malaria parasite Plasmodium falciparum (W2). The cytotoxicity evaluation was accomplished using Hep G2 cells and SI index was calculated for every molecule. Some of the quinoline derivatives have shown high antimalarial activity, with IC50 values in the range of 1.72-8.66 µM, low cytotoxicity, with CC50>1000 µM and selectivity index (SI) in the range of 20-100, with some compounds showing SI>800. Therefore, the quinolinotriazole hybrids could be considered a very important step on the development of new antimalarial drugs.

Keywords:
7-Chloroquinolinotriazoles; Quinolines; Click reaction; Plasmodium falciparum ; Antimalarial activity


INTRODUCTION

Malaria is a deadly disease that affects mostly third-world countries, being responsible for 219 million cases and 435.000 deaths in 2017 alone, according to the World Health Organization 2018 report (WHO, 2018WHO. World Malaria Report 2018 [Internet]. WHO. Geneva: World Health Organization. 2018.). The transmission of malaria occurs through blood transfusions or the mosquito bite of the genus Anopheles and it is caused by protozoan parasites of the genus Plasmodium, including the human parasites P. malariae, P. ovale, P. knowlesi, P. vivax and P. falciparum. The last two are responsible for the majority of human infections around the world, with P. falciparum being the most lethal (Harvard Medical School, 2013Harvard Medical School. Malaria [Internet]. Boston. 2013.).

If not treated soon enough, the P. falciparum malaria, can become severe and often leads to death, therefore, it is important to have fast and effective treatment measures. The resistance of Plasmodium sp. to different medicines is a constant concern, because it has already shown resistance to previous aminoquinoline drug generations, such as quinine(1) and its molecular simplification (Barreiro, 2002Barreiro EJ. Estratégia de simplificação molecular no planejamento racional de fármacos: a descoberta de novo agente cardioativo. Quim Nova. 2002;25(6b):1172-80.), mefloquine (2), mepacrine (3) and its well-known molecular simplification chloroquine (CQ) (4) (2017) (Figure I). Other drug classes, including artemisinin and atovaquone have recent cases of resistance (Mishra et al., 2016Mishra M, Mishra VK, Kashaw V, Iyer AK, Kashaw SK. Comprehensive review on various strategies for antimalarial drug discovery. Eur J Med Chem. 2016.). Due to this fact, research studies seeking new compounds are increasing, and it is evidenced by the vast number of leads and exploratory drugs against malaria (Okombo, Chibale, 2017Okombo J, Chibale K. Insights into Integrated Lead Generation and Target Identification in Malaria and Tuberculosis Drug Discovery. Acc Chem Res. 2017;50(7):1606-16.).

Once the host is infected, several events take place. Firstly, the parasite goes to the liver and replicates several times until it reaches the blood stream. After that, the parasite settles inside the red blood cells of its host, where it degrades hemoglobin (Hb) to use it as a source of amino acids for its own proteins (Sherman, Tanigoshi, 1970Sherman IW, Tanigoshi L. Incorporation of 14C-amino-acids by malaria (Plasmodium lophurae) IV. In vivo utilization of host cell haemoglobin. Int J Biochem. 1970,1(5):635-7.). When the Hb is degraded inside the food vacuole, heme is released and autoxidated in hematin, that is converted by the parasite in hemozoin by biocrystallization (Pagola et al., 2000Pagola S, Stephens PW, Bohle DS, Kosar AD, Madsen SK. The structure of malaria pigment β-haematin. Nature. 2000;404(6775):307-10.), which then can be disposed (Brown, 1911Brown WH. Malarial Pigment (so-called Melanin): Its Nature and Mode of Production. J Exp Med. 1911;13(2):290-9.). Both free heme and free hematin are toxic to the parasite (Ladan, Nitzan, Malik, 1993Ladan H, Nitzan Y, Malik Z. The antibacterial activity of haemin compared with cobalt, zinc and magnesium protoporphyrin and its effect on potassium loss and ultrastructure of Staphylococcus aureus. FEMS Microbiol Lett. 1993;112(2):173-7.), subsequently, the formation of hemozoin is essential to its survival. The chloroquinoline core present in CQ is the pharmacophoric group, since it has a binding functionality with hematin (Sullivan et al., 1996Sullivan DJ, Gluzman IY, Russell DG, Goldberg DE. On the molecular mechanism of chloroquine’s antimalarial action. Proc Natl Acad Sci USA. 1996;93(21):11865-70.), thus preventing the polymerization from the toxic heme (Ziegler, Linckand, Wright, 2001Ziegler J, Linck R, Wright D. Heme Aggregation Inhibitors: Antimalarial Drugs Targeting an Essential Biomineralization Process. Curr Med Chem. 2001;8(2):171-89.), which then, accumulates inside the food vacuole, leading to parasitic death (Coronado, Nadovichand, Spadafora, 2014Coronado LM, Nadovich CT, Spadafora C. Malarial hemozoin: From target to tool. Biochim Biophys Acta. 2014;1840(6):2032-41.). This antimalarial effect is improved by the nitrogen binder in the side chain, increasing the core activity due to electron donation. Besides, CQ is widely studied because of its easy preparation and low toxicity and side-effects (Kouznetsov, Gó Mez-Barrio, 2009Kouznetsov V V, Gó Mez-Barrio A. Recent developments in the design and synthesis of hybrid molecules based on aminoquinoline ring and their antiplasmodial evaluation. Eur J Med Chem. 2009;44:3091-113.).

FIGURE 1
Structures of quinine (1), mefloquine (2), mepacrine (3) chloroquine (4), compounds synthesize in previous projects (5) and proposed compounds (6).

Several compounds were made in some of those studies (Guillon et al., 2011Guillon J, Mouray E, Moreau S, Mullié C, Forfar I, Desplat V, et al. New ferrocenic pyrrolo[1,2-a]quinoxaline derivatives: Synthesis, and in vitro antimalarial activity e Part II. Eur J Med Chem. 2011;46(6):2310-26.; Kumar et al., 2008Kumar A, Srivastava K, Raja Kumar S, Puri SK, Chauhan PMS. Synthesis and bioevaluation of hybrid 4-aminoquinoline triazines as a new class of antimalarial agents. Bioorg Med Chem Lett. 2008;18(24):6530-3.; Melato et al., 2008Melato S, Prosperi D, Coghi P, Basilico N, Monti D. A Combinatorial Approach to 2,4,6-Trisubstituted Triazines with Potent Antimalarial Activity: Combining conventional synthesis and microwave-assistance. Chem Med Chem. 2008,3(6):873-6.; Pérez et al., 2012Pérez BC, Teixeira C, Figueiras M, Gut J, Rosenthal PJ, Gomes JRB, et al. Novel cinnamic acid/4-aminoquinoline conjugates bearing non-proteinogenic amino acids: Towards the development of potential dual action antimalarials. Eur J Med Chem. 2012;54:887-99.; Sunduru et al., 2009Sunduru N, Sharma M, Srivastava K, Rajakumar S, Puri SK, Saxena JK, et al. Synthesis of oxalamide and triazine derivatives as a novel class of hybrid 4-aminoquinoline with potent antiplasmodial activity. Bioorg Med Chem. 2009;17(17):6451-62.), combining different molecules with CQ core with several molecular groups, such as amides (Joshi et al., 2013Joshi MC, Wicht KJ, Taylor D, Hunter R, Smith PJ, Egan TJ. In vitro antimalarial activity, β-haematin inhibition and structure-activity relationships in a series of quinoline triazoles. Eur J Med Chem. 2013;69:338-47.) chalcones (Guantai et al., 2010Guantai EM, Ncokazi K, Egan TJ, Gut J, Rosenthal PJ, Smith PJ, et al. Design, synthesis and in vitro antimalarial evaluation of triazole-linked chalcone and dienone hybrid compounds. Bioorg Med Chem. 2010,18(23):8243-56.; Kumar et al., 2017Kumar S, Saini A, Gut J, Rosenthal PJ, Raj R, Kumar V. 4-Aminoquinoline-chalcone/-N-acetylpyrazoline conjugates: Synthesis and antiplasmodial evaluation. Eur J Med Chem. 2017;138:993-1001.), naphthoquinones (da Silva et al., 2012da Silva EN, de Melo IMM, Diogo EBT, Costa VA, de Souza Filho JD, Valença WO, et al. On the search for potential anti-Trypanosoma cruzi drugs: Synthesis and biological evaluation of 2-hydroxy-3-methylamino and 1,2,3-triazolic naphthoquinoidal compounds obtained by click chemistry reactions. Eur J Med Chem. 2012;52:304-12.), isatins (Raj et al., 2013Raj R, Singh P, Singh P, Gut J, Rosenthal PJ, Kumar V. Azide-alkyne cycloaddition en route to 1H-1,2,3-triazoletethered 7-chloroquinoline-isatin chimeras: Synthesis and antimalarial evaluation. Eur J Med Chem. 2013;62:590-6.), pyrimidines (Chopra, Chibale, Singh, 2018Chopra R, Chibale K, Singh K. Pyrimidine-chloroquinoline hybrids: Synthesis and antiplasmodial activity. Eur J Med Chem. 2018;148:39-53.) and also a previous work from the group (Pereira et al., 2014Pereira GR, Brandão GC, Arantes LM, De Oliveira HA, De Paula RC, Do Nascimento MFA, et al. 7-Chloroquinolinotriazoles: Synthesis by the azide-alkyne cycloaddition click chemistry, antimalarial activity, cytotoxicity and SAR studies. Eur J Med Chem. 2014;73:295-309.), consisting on the union of the triazole moiety straight to the quinoline ring, which has shown that the activity decreased due to inductive and mesomeric effects. More studies have shown that the quinoline nucleus containing achloromoiety at the seventh position and a basic side chain at the terminal position has very good antimalarial activity (O’Neill et al., 1998O’Neill PM, Bray PG, Hawley SR, Ward SA, Park BK. 4-Aminoquinolines-past, present, and future: a chemical perspective. Phmmmol Ther. 1998;77(1):29-58.). Despite many molecules with the chloroquinoline core were already made, containing small modifications in the side chain (Manohar, Khanand Rawat, 2011Manohar S, Khan SI, Rawat DS. Synthesis of 4-aminoquinoline-1,2,3-triazole and 4-aminoquinoline1,2,3-triazole-1,3,5-triazine hybrids as potential antimalarial agents. Chem Biol Drug Des. 2011;78(1):124-36.), there are still many different groups in the end of these chairs that still need to be exploited.

Thereby, several molecules have been made to fulfill this approach, this time with an aliphatic chain containing 2 or 3 carbons between these centers, becoming more similar to chloroquine, as well as a nitrogen linker, that improves activity due to its capability of donating electron density to the ring, raising the antiplasmodial activity. These new compounds were made using the process known as Cu-mediated “click” chemistry (Rostovtsev et al., 2002Rostovtsev VV, Green LG, Fokin VV, Sharpless KB. A stepwise huisgen cycloaddition process: copper(I)-catalyzed regioselective “ligation” of azides and terminal alkynes. Angew Chemie Int Ed Engl. 2002;41(14):2596-9.), which is presently being extensively used (Kolb, Finnand, Sharpless, 2001Kolb HC, Finn MG, Sharpless KB. Click Chemistry: Diverse Chemical Function from a Few Good Reactions. Angew Chem Int Ed Engl. 2001;40(11):2004-21.), as well for the enhancement of the activity in natural products (Bakka et al., 2017Bakka TA, Strøm MB, Andersen JH, Gautun OR. Synthesis and antimicrobial evaluation of cationic low molecular weight amphipathic 1,2,3-triazoles. Bioorg Med Chem Lett. 2017;27(5):1119-23.; Hou et al., 2017Hou W, Luo Z, Zhang G, Cao D, Li D, Ruan H, et al. Click chemistry-based synthesis and anticancer activity evaluation of novel C-14 1,2,3-triazole dehydroabietic acid hybrids. Eur J Med Chem. 2017;138:1042-52.; Mistry, Pateland, Keum, 2017Mistry B, Patel R V., Keum Y-S. Access to the substituted benzyl-1,2,3-triazolyl hesperetin derivatives expressing antioxidant and anticancer effects. Arab J Chem. 2017;10(2):157-66.; Yamada et al., 2016Yamada R, Hiraizumi M, Narita S, Sakurai K. Two-step synthesis of a clickable photoaffinity probe from an anticancer saponin OSW-1 and its photochemical reactivity. Asian J Org Chem. 2016;5(3):330-4.). This method made it possible to easily produce hybrid molecules by combining several terminal alkynes and two different organic azides, with a chloroquinoline core and a side chain linked at the terminal position, with changes in the number of carbon atoms. Once it a study has shown that hybrid compounds present advantages over a single drug or multicomponent combination therapy related to drug resistance, solubility and formulation (Chopra, Chibale, Singh, 2018Chopra R, Chibale K, Singh K. Pyrimidine-chloroquinoline hybrids: Synthesis and antiplasmodial activity. Eur J Med Chem. 2018;148:39-53.), hence the click chemistry emerged as a promising alternative on antimalarials chemotherapy.

CHEMISTRY

The building blocks for the final molecules (9) were obtained through a synthesis route started with the commercial reagent 4,7-dichloroquinoline (6). The inception of a carbonic chain was carried out using ethanolamine and 3-amino-1-propanol providing a 4-aminoquinoline (7) and then the hydroxyl moiety was replaced for bromine (8) with hydrobromic acid in toluene. At the end, an azide was introduced to the molecule through a bimolecular nucleophilic substitution (SN2) providing the key intermediaries for the synthesis (Figure 2).

The final products were obtained through click chemistry according to the methodology described by Sharpless and co-workers (Rostovtsev et al., 2002Rostovtsev VV, Green LG, Fokin VV, Sharpless KB. A stepwise huisgen cycloaddition process: copper(I)-catalyzed regioselective “ligation” of azides and terminal alkynes. Angew Chemie Int Ed Engl. 2002;41(14):2596-9.) that consists on a Cu(I)-catalyzed azide-alkyne 1,3 dipolar cycloaddition (CuAAC) and provided 1,2,3-triazole 1,4 disubstituted hybrids (Melato et al., 2008Melato S, Prosperi D, Coghi P, Basilico N, Monti D. A Combinatorial Approach to 2,4,6-Trisubstituted Triazines with Potent Antimalarial Activity: Combining conventional synthesis and microwave-assistance. Chem Med Chem. 2008,3(6):873-6.; da Silva et al., 2012da Silva EN, de Melo IMM, Diogo EBT, Costa VA, de Souza Filho JD, Valença WO, et al. On the search for potential anti-Trypanosoma cruzi drugs: Synthesis and biological evaluation of 2-hydroxy-3-methylamino and 1,2,3-triazolic naphthoquinoidal compounds obtained by click chemistry reactions. Eur J Med Chem. 2012;52:304-12.; Sunduru et al., 2009Sunduru N, Sharma M, Srivastava K, Rajakumar S, Puri SK, Saxena JK, et al. Synthesis of oxalamide and triazine derivatives as a novel class of hybrid 4-aminoquinoline with potent antiplasmodial activity. Bioorg Med Chem. 2009;17(17):6451-62.). The reactions of the obtained azide and commercial alkynes were carried out in methanol and water, in the presence of CuSO4.5H2O, NaHCO3 and ascorbic acid, stirring at room temperature overnight. Afterwards, the products were purified via chromatographic column and the yields varied around 68 to 89% (Figure 3).

FIGURE 2
Obtainment of the building block (9) from 4,7-dichloroquinoline employed on the synthesis.
FIGURE 3
Obtainment of quinolyl triazole hybrids via click reaction.

The aminoquinolinotriazole hybrid structures were assigned on the basis of spectrometric data including HRMS-ESI-IT-TOF, IR 1H and 13C NMR.

BIOLOGICAL ACTIVITY

Continuous cultures of Plasmodium falciparum

The chloroquine-resistant and mefloquine-sensitive (De Andrade-Neto et al., 2004Andrade-Neto VF, Goulart MOF, Da Silva Filho JF, Da Silva MJ, Pinto MDCFR, Pinto AV, et al. Antimalarial activity of phenazines from lapachol, β-lapachone and its derivatives against Plasmodium falciparum in vitro and Plasmodium berghei in vivo. Bioorganic Med Chem Lett. 2004;14(5):11459.) P. falciparum W2 clone was kept in a continuous culture at 37 ºC in human erythrocytes using the candle jar method (Trager, Jensen, 1976Trager W, Jensen JB. Human malaria parasites in continuous culture. Science. 1976;193(4254):673-5.). The antimalarial effect of the compounds was measured by the pLDH assay (Noedl et al., 2005Noedl H, Bronnert J, Yingyuen K, Attlmayr B, Kollaritsch H, Fukuda M. Simple histidine-rich protein 2 double-site sandwich enzyme-linked immunosorbent assay for use in malaria drug sensitivity testing. Antimicrob Agents Chemother. 2005;49(8):3575-7.). The parasites were kept in complete culture medium (RPMI) containing hypoxanthine (300 µM), sodium bicarbonate (21 mM), HEPES (25 mM), gentamicin (40 µg/mL) and D-glucose (11 mM), which were supplemented by 10% human plasma on culture dishes, with daily changes of medium. All experiments were performed in triplicate. The compounds were tested in triplicate at each concentration. The cultures with predominantly ring-stage parasites were concentrated by sorbitol-synchronization (Lambros, Vanderberg, 1979Lambros C, Vanderberg JP. Synchronization of Plasmodium falciparum erythrocytic stages in culture. J Parasitol. 1979;65(3):418-20.). A suspension of red blood cells with 1.5% hematocrit and 0.05% parasitemia was distributed in a 96-well microtiter plate (180 µL/well). The parasite growth was evaluated by the pLDH assay, as summarized below.

Evaluation of the in vitro antimalarial activity by the pLDH assay

The antimalarial effects of the compounds and controls were measured by the lactate dehydrogenase of Plasmodium falciparum (pLDH) assay as previously described (Piper et al., 1993Piper RC, Williams JA, Makler MT, Gibbins BL, Hinrichs DJ, Ries JM, et al. Parasite lactate dehydrogenase as an assay for Plasmodium falciparum drug sensitivity. Am J Trop Med Hyg. 1993;48(6):739-41.), with slight modifications. Briefly, ring-stage parasites in sorbitol-synchronized blood cultures were added to 96-well culture plates at 1% hematocrit and 2% parasitemia and then incubated with the test drugs that were diluted in complete medium, from 50 mg/mL stock solutions in DMSO, at a final concentration of 0.002% (v/v) and stored at -20 ºC. After 48 h of incubation, the plates were frozen at -20 ºC for 24 h and thawed for the pLDH assay. The hemolyzed cultures were transferred to another 96well culture plate. Then, Malstat® reagents, tetrazolium nitroblue and phenazine etazulfate salt (NBT/PES) were added. After 1 h of incubation at 37 ºC in the dark, the absorbance was read at 570 nm in a spectrophotometer (Infinite®200 PRO, Tecan). The results were evaluated with the software Microcal Origin 8.5 for determination of the dose-response curves plotted with sigmoidal fit (de Pilla Varotti et al., 2008de Pilla Varotti F, Botelho ACC, Andrade AA, de Paula RC, Fagundes EMS, Valverde A, et al. Synthesis, Antimalarial Activity, and Intracellular Targets of MEFAS, a new hybrid compound derived from mefloquine and artesunate. Antimicrob Agents Chemother. 2008;52(11):3868-74.). The IC50 was determined by comparison with the controls using standard drugs and without drugs.

Cytotoxicity evaluation in human hepatoma cell cultures - Hep G2 cells

The hepatoma cells Hep G2 were maintained in 75 cm2 sterile culture flasks (Corning®), in 5% CO2 and at 37 ºC, with RPMI 1640 culture medium supplemented with penicillin (10 U/mL), streptomycin (100 g/mL) and 5% FBS, the medium being changed twice a week. The cells were maintained in weekly passages (at 1:3 dilutions in sterile culture flasks) and grown to 80% (Twentyman, Luscombe, 1987Twentyman P, Luscombe M. A study of some variables in a tetrazolium dye (MTT) based assay for cell growth and chemosensitivity. Br J Cancer. 1987;56(3):279-85.). After being trypsinized (0.05% trypsin/0.5 mM EDTA) and plated on 96 well microplates (Calvocalle et al., 1994Calvocalle JM, Moreno A, Eling WMC, Nardin EH. In Vitro Development of Infectious Liver Stages of P. yoelii and P. berghei Malaria in Human Cell Lines. Exp Parasitol. 1994;79(3):362-73.), they were used for experiments. When confluent, the monolayers were trypsinized, washed, counted, diluted in complete medium, distributed in 96well microplates (4 x 103 cells/well) and then incubated for another 24 h at 37 ºC. The test samples and controls were diluted to a final concentration of 0.02% DMSO in culture medium to yield four concentrations in serial dilutions starting at 1000 mg/mL. After24 h incubation at 37 ºC, 18 µL of MTT solution (5 mg/mL in PBS) were added to each well, followed by another 90 min incubation at the same temperature. Then, the supernatant was removed and 180 µL of DMSO were added to each well. The culture plates were read in a spectrophotometer with a 570 nm filter (Twentyman, Luscombe, 1987Twentyman P, Luscombe M. A study of some variables in a tetrazolium dye (MTT) based assay for cell growth and chemosensitivity. Br J Cancer. 1987;56(3):279-85.). The minimum cytotoxicity concentration was determined as described previously, with minor modifications (DMSO was used instead of ethanol for solubilizations and chloroquine was used instead of primaquine for the positive control). Each test was performed in duplicate, the concentration that killed 50% of the cells (CC50) was determined (Madureira et al., 2002Madureira M, Paula Martins A, Gomes M, Paiva J, Proença Da Cunha A, Do Rosário V. Antimalarial activity of medicinal plants used in traditional medicine in S. Tomé and Príncipe islands. J Ethnopharmacol. 2002;81(1):23-9.). Then the selectivity index (SI) for the antimalarial activity was calculated based on the ratio between CC50 and IC50 for the in vitro activity against P. falciparum (de Sá et al., 2009De Sá MS, Costa JFO, Krettli AU, Zalis MG, De Azevedo Maia GL, Sette IMF, et al. Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice. Parasitol Res. 2009;105(1):275-9.).

RESULTS AND DISCUSSION

The initial proposed route using mesylation was optimized through the substitution of this step for the bromination, being far more easily to obtain the intermediate employed in the final compounds. The size influence of the side chain was taken in consideration for this work. After synthesize molecules with side chains with 2 carbon atoms, a different approach was made with a 3-carbon atom side chain, since it is more similar to chloroquine. The thirty-eight quinolinotriazole hybrids obtained had their antiplasmodic activity evaluated in vitro against P. falciparum W2 strain sensitive to mefloquine and chloroquine-resistant. The values of CC50 for the cytotoxicity (Hep G2A16 cells), IC50values according to pLDH method and the respective SI of the molecules are shown in Table I.

TABLE I
Quinolinotriazole products 10-28, in vitro antimalarial activity (IC50 µM) against P. falciparum (W2 clone), cytotoxicity (CC50 µM, Hep G2A16 cells) and selectivity index (SI)

Despite, other groups have already exploited triazol quinolinic moieties similar to these compounds, therefore, it is essential to fulfill the empty spaces and investigate small changes that could answer a number of questions in the path of finding new antimalarial drugs. Several side chain groups were produced including aliphatic and aromatic moieties, alcohol, halide, amine and ether side chain compounds. The most active compound (21b) was ever more active then CQ and its SI of 1351.35 demonstrate a promising compound for future in vivo evaluation. In addition, a similar compound (26b) containing 3 side chain carbons and a phenyl substituted group also had promising results.

SAR analysis of the most active compounds confirmed that side chain containing 3 carbons and a phenyl group increase activity and future work could exploit other substitutions in the aromatic ring. The most active compounds containing 2 side chain carbons are a ciclohexyl moiety (19a) and a napthyl substituted moiety in the end, demonstrating a pattern that a hydrophobic pocket might be responsible for the most active compounds in this study. Molecules containing different amines (15, 16 and 17a and b) were also active and their SAR with CQ demonstrated that the inclusion of a triazol ring between this amine and quinoline group increase cytotocixity and low SI. Previous work from this group, demonstrated that some quinolyl terminal alcohol compounds were active, but in this work, it could be concluded that despite moderate results, other substitutions were more promising. Several aromatic side chain compounds were evaluated, including compounds 21-28a 21-28b and they showed more promising results than the non-aromatic side chains. Thirteen compounds presented IC50<10 µM. By analyzing the selectivity index, it is possible to assume that the most promising compounds were 21b and 26b with SI of 1351.35 and 813.01 respectively, the first one being more selective than CQ.

The resistance to the currently used drugs and the complex life cycle are the main reasons that Plasmodium sp is responsible for most deaths caused by malaria. For this reason, the research of new effective antimalarial drugs is of essential and scientists all over the world are using different approaches and methods to create a compound to satisfy this need.

The concept used in this work was the design of new molecules, created of a chroloquinoline moiety, known for its antimalarial activity, linked with different side chains containing 2 or 3 carbon atoms to prevent the decreasing of activity due to inductive and mesomeric effects, a nitrogen atom to donate density to the ring and a chloro moiety at the seventh position of the ring, improving even more the antimalarial effect. Several commercially terminal alkynes were then combined with this core via “click” chemistry by the copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) reaction, creating unprecedented ntiplasmodial hybrid drugs. Triazole quinolyl molecules are a promising class of molecules in finding new antimalarial prototypes.

CONCLUSION

The search for a new arsenal of antimalarial medicines with effectiveness is an important approach.

Thus, small changes in existing molecules is an interesting procedure to find new molecules.

Thus, new molecules were created based on chloroquinoline moiety, known for its antimalarial activity. Created molecules have side chains containing 2 or 3 carbon atoms still containing a nitrogen atom linked to 7-cloroquine core. The introduction of the triazole in the end of these aliphatic chairs produced several interesting molecules. This approach used commercially terminal alkynes via “click” or copper(I)-catalyzed alkyneazide cycloaddition (CuAAC) reaction, thus creating unprecedented antiplasmodial hybrid molecules. Triazole quinolyl molecules are a promising class of molecules in finding new antimalarial prototypes.

EXPERIMENTAL SECTION

General

All the chemicals and reagents were acquired commercially and used as received. The reactions were carried out without inert atmosphere in standard dry glassware. They were also controlled via thin layer chromatography (TLC) using silica gel 60 with fluorescent indicators (e.g., silica F-254 gel, Macherey-Nagel) unless noted otherwise and visualized by exposure on iodine chamber, by spraying anisaldehyde acid, Hanissam reagent (ceric ammonium molibidate-CAM), Dragendorff solution or even using ultraviolet light source at 254 nm. The intermediaries were purified via crystallization, liquid phase extraction or filtration and the products with silica chromatographic column (Sigma-Aldrich, 0.040 to 0063 mm, 230-400 mesh American Society for Testing and Materials (ASTM)). Concentration and evaporation were performed on standard Ika rotavapor under low pressure using vacuum pump. Melting points (mps) were measured with a Buchi M-560 melting point apparatus and are uncorrected. Infrared spectra were recorded on FT-IR, Shimadzu IRAffinity-1 with ATR system and are reported in wave numbers (cm-1). Mass spectra data were obtained by liquid chromatography coupled to a Waters Acquity TQD UPLC/MS/MS system mass spectrometer using electrospray ionization (ESI). The 1H and 13C NMR spectra were measured on a Bruker Advance DPX 200, Fourier 300HDand DRX400 with FT analysis. The chemical shifts δ (ppm) relates to SiMe4 and coupling constants (J) are given in hertz. The deuterated solvent used were MeOD, CD3OD, CDCl3 or DMSO-d6. All 2D NMR data were recorded at 400 MHz (Bruker DRX400), heteronuclear single quantum coherence (HSQC) using J 145 Hzand heteronuclear multiple-bond correlation (HMBC) using J 8 Hz.

Materials

The following materials were used: 4,7-Dichloroquinoline, ethanolamine, 3-amino-1-propanol, bromidric acid, prop-2-yn-1-ol, but-3-yn-1-ol, pent-4-yn1-ol, pent-1-yn-3-ol, 2-methylbut-3-yn-2-ol, prop-2-yn-1amine, N-methylprop-2-yn-1-amine, N,N-dimethylprop-2yn-1-amine, 1-ethynylcyclopentanol, ethynylcyclohexane, 1-ethynylcyclohexanol, ethynylbenzene, 2-phenylbut-3-yn2-ol, 1-phenylprop-2-yn-1-ol, 1-ethynyl-4-methylbenzene, 1-ethynyl-4-methoxybenzene, 1-ethynyl-4-fluorobenzene, 4-ethynyl-N,N-dimethylaniline, 2-ethynyl-6methoxynaphthalene, D-glucose, HEPES, hypoxanthine, gentamicin, D-sorbitol, PBS, BSA, TMB, FBS, penicillin, streptomycin, tripsin/EDTA and DMSO were obtained from Sigma-Aldrich® USA, Ltd. The glassware was purchased from Hialoquímica Ltda; Toluol, sodium azide, dimethylformamide, methanol, sodium ascorbate, sodium bicarbonate and copper(I) sulphate pentahydrate were obtained from Synth; MPFG-55P and MPFM-55A antibodies were purchased from ICLLABS®; sulfuric acid, sodium bicarbonate and sodium sulphate were obtained from FMaia and used without further purification.

Synthesis and Characterization

All the compounds were synthesized and characterization was made by NMR, IR and MS.

Obtainment of the chloroquinolinyl alcohol

The 4,7-dichloroquinoline was mixed with the respective aminoalcohol in 1:12.5 equivalent (ethanolamine for 7a or 3-amine-1-propanol for 7b) and the system stayed at 110 ºC for two hours. Then the brown solution obtained was crystallized with ethyl acetate and water, while the precipitate was filtered under vacuum. After dried, the product presented itself as a white powder with yield of 91%.

2-((7-chloroquinolin-4-yl) amino) ethan-1-ol (7a)

White crystalline powder. m.p. 217.0-219.0 ºC, IR (λmax, cm-1): 3306, 3066, 2923, 2816, 1614, 1580, 1063, 800, 763. 1H NMR (200 MHz, MeOD): δ8.32 (d, 1H, J = 5.8, H-2), 8.06 (d, 1H, J = 9.0, H-5), 7.74 (d, 1H, J = 2.2, H-8), 7.36 (dd, 1H, J = 2.2 e 9.0, H-6), 6.53 (d, 1H, J = 5.8, H-3), 3.86 (2H, t, J = 5.7, ArNHCH2CH2-), 3.47 (2H, t, J = 5.7, ArNHCH2-). 13C NMR (50 MHz, CDCl3): δ151.8 (C-2), 150.2 (C-3), 149.0 (C-8), 133.3 (C-6), 127.4 (C-7), 123.9 (C-4), 123.9 (C-5), 117.4 (C-9), 98.6 (C-2), 58.7 (C-11), 45.0 (C-10).

3-((7-chloroquinolin-4-yl) amino) propan-1-ol (7b)

White crystalline powder. m.p. 149.7-151.7 ºC, IR (λmax, cm-1): 3374, 3312, 2896, 2757, 1612, 1584, 854, 800. 1H NMR (200 MHz, MeOD): δ8.22 (d, 1H, J = 5.8, H-2), 7.89 (d, 1H, J = 8.8, H-5), 7.65 (d, 1H, J = 2.0, H-8), 7.23 (dd, 1H, J = 2.0 e 9.0, H-6), 6.37 (d, 1H, J = 5.8, H-3), 3.66 (2H, t, J = 6, H-13), 3.34 (2H, t, J = 6.8, H-11), 1.87 (2H, q, J = 6.2 e 12.8, H-12). 13C NMR (50 MHz, CDCl3): δ152.6 (C-2), 152.3 (C-3), 149.5 (C-8), 136.2 (C-6), 127.5 (C-7), 125.9 (C-4), 124.1 (C-5), 118.6 (C-9), 99.5 (C-2), 60.8 (C-12), 41.3 (C-10), 32.1 (C-11).

Obtainment of the chloroquinolinyl bromide

The quinolinyl alcohol was mixed with hydrobromic acid and toluene and maintained under reflux for one hour. After this period, a Dean-Stark Apparatus was docked and the system maintained under reflux for one more hour. Then the solution was eluted with dichloromethane and methanol, then it was washed with a 1M solution of sodium bicarbonate. The solvent extraction was carried out with a rotavapor coupled with a vacuum pump and the product obtained was a light-yellow powder with yield of 88%.

N-(2-bromoethyl)-7-chloroquinolin-4-amine (8a)

Yellowish powder. m.p. 142.0-144.4 ºC, IR (λmax, cm-1): 3628, 2970, 2378, 2347, 2309, 1582, 810. 1H NMR (300 MHz, MeOD): d 8.27 (d, 1H, J1-2 = 6.23, H-1), 7.97 (d, 1H, J4-5 = 9.4, H-4), 7.69 (s, 1H, H-7), 7.31 (d, 1H, J5-4 = 9.26, H-5), 6.46 (d, 1H, J2-1 = 5.39, H-2), 3.69-3.75 (m, 2H, H-11 and H-11’), 3.53-3.56 (m, 2H, H-10 and H-10’), 3.21 (s, 1H, -NH). 13C NMR (100 MHz, CDCl3): δ154.8 (C-3), 152.0 (C1), 151.8 (C-8), 139.2 (C-6), 130.1 (C-7), 129.0 (C-4), 126.8 (C-5), 121.2(C-9), 102.3 (C-2), 48.2 (C-10), 32.8 (C-11).

N-(3-bromopropyl)-7-chloroquinolin-4-amine (8b)

Yellowish powder. m.p. 323.2-325.0 ºC, IR (λmax, cm1): 3728, 3701, 3628, 2384, 2351, 2307, 1580, 814. 1H NMR (300 MHz, MeOD): d 8.72 (d, 1H, J1-2 = 5.48, H-1), 8.30 (d, 1H, J4-5 = 8.96, H-4), 8.17 (s, 1H, H-7), 7.70 (d, 1H, J5-4 = 9.08, H-5), 6.81 (d, 1H, J2-1 = 5.49, H-2), 3.88-3.92 (m, 4H, H-11, H-11’, H-12 and H-12’), 2.62-2.66 (m, 2H, H-10 and H-10’), 1.62 (s, 1H, -NH). 13C NMR (50 MHz, MeOD): δ151.4 (C-3), 148.6 (C-1), 135.7 (C-8), 127.3 (C-6), 125.7 (C-7), 122.9 (C-4), 117.8 (C-5), 99.0(C-9), 41.6 (C-2), 31.5 (C-10), 31.2 (C-11), 30.1 (C-12).

Obtainment of the chloroquinolinyl azide

In anhydrous DMF, sodium azide was mixed with the quinolinyl bromide and stirred overnight. The work-up employed dichloromethane and water, then the product was filtered with silica gel. After dried with rotavapor, it presented itself as a white-yellow powder with 89% yield.

N-(2-azidoethyl)-7-chloroquinolin-4-amine (9a)

White fine powder. m.p. 146.2-147.7 ºC, IR (λmax, cm-1): 3229, 3065, 2924, 2856, 2091; 1571, 1549. 1H NMR (200 MHz, CDCl3): δ8.26 (d, 1H, J = 5.6, H-2), 7.95 (d, 1H, J = 9.0, H-5), 7.67 (d, 1H, J = 2.0, H-8), 7.27 (dd, 1H, J = 2.0 e 9.0, H-6), 6.44 (d, 1H, J = 5.6, H-3), 3.49 (4H, sl, 2 H-11 e 2 H-12). 13C NMR (50 MHz, CDCl3): δ152.4 (C-2), 152.3 (C-3), 149.6 (C-8), 136.4 (C-6), 127.6 (C-7), 126.2 (C-5), 124.2 (C-5), 118.7 (C-9), 99.7 (C-2), 50.6 (C-11), 43.3 (C-10).

N-(3-azidopropyl)-7-chloroquinolin-4-amine (9b)

White fine powder. m.p. 153.9-156.5 ºC, IR (λmax, cm-1): 3217, 3066, 2940, 2092, 1611, 1574, 1492, 1282. 1H NMR (200 MHz, CDCl3): δ8.54 (d, 1H, J = 5.2, H-2), 7.96 (d, 1H, J = 2.0, H-8), 7.67 (d, 1H, J = 9.0, H-5), 7.37 (dd, 1H, J = 2.0 e 9.0, H-6), 6.44 (d, 1H, J = 5.4, H-3), 3.54 (t, 2H, J = 6.0, H-13), 3.44 (t, 2H, J = 5.6, H-11), 2.02 (q, 2H, J = 6.6 e 12.8, H-12). 13C NMR (50 MHz, MeOD): δ152.6 (C-3), 152.3 (C-2), 149.5 (C-8), 136.3 (C-6), 127.5 (C-7), 126.0 (C-5), 124.4 (C-5), 118.7 (C-9), 99.6 (C-2), 50.3 (C-12), 41.1 (C-10), 28.7 (C-11).

General procedure of click reaction

Commercial alkyne-compounds and chloroquinoline azide were dissolved in MeOH (1 mL), followed by the addition of NaHCO3 (0.3 equivalents), CuSO4.5H2O (0.3 equivalents) and an aqueous solution of sodium ascorbate (0.6 equivalents) (0.5 mL) freshly prepared. The system stirred overnight and it was stopped when the TLC indicated the end of the reaction. The work-up of the reaction mixture was done with CH2Cl2 and water (3x10 mL), dried over Na2SO4 and finally purified by column chromatography with DCM/MeOH (98:2 v/v).

(1-(2-((7-chloroquinolin-4-yl) amino) ethyl)-1H-1,2,3-triazol-4-yl) methanol (10a)

White powder. m.p. 201.9-203.9 ºC, IR (λmax, cm-1): 3285, 3123, 2955, 2924, 2384, 2349, 2307, 1585, 1456, 1049, 810. 1H NMR (400 MHz, MeOD): δ8.33 (d, 1H, J = 7.2, H-2), 8.27 (d, 1H, J =9.2, H-5), 8.00 (s, 1H, H-13), 7.86 (d, 1H, J = 2, H-8), 7.63 (dd, 1H, J = 2.0 e 9.2, H-6), 6.71 (d, 1H, J = 6.8, H-3), 4.81 (t, 2H, J = 5.2, H-12), 4.63 (s, 2H, H-15), 4.14 (t, 2H, J = 5.6, H-11). 13C NMR (100 MHz, CDCl3): δ157.9 (C-3), 144.1 (C-2), 141.2 (C-8), 140.0 (C-13), 128.9 (C-7), 125.8 (C-4), 120.4 (C-5), 116.9 (C-9), 99.6 (C-2), 56.2 (C-14), 49.7 (C-11), 44.4 (C-10). HRMSESI-IT-TOF: m/z was calculated as C14H15ClN5O 303.09, and found 303.05 as a result.

(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)methanol (10b)

White powder. m.p. 193.2-195.0 ºC, IR (λmax, cm-1): 3351, 3123, 3069, 2958, 2924, 2802, 2366, 2340, 1588, 1374, 1058, 799. 1H NMR (300 MHz, MeOD): d 8.41 (d, 1H, J1-2 = 4.78, H-1), 8.01-8.11 (m, 1H, H-4), 7.84-7.89 (m, 2H, H-7 and H-13), 7.46-7.49 (m, 2H, H-5 and -NH), 6.48 (d, 1H, J2-1 = 5.71, H-2), 4.59-4.62 (m, 5H, H-12, H-12’, H-15, H-15’ and -OH), 3.46-3.51 (m, 2H, H-11 and H-11’), 2.40-2.44 (m, 2H, H-10 and H-10’). 13C NMR (100 MHz, CDCl3): δ155.2 (C-3), 155.3 (C-1), 154.1 (C-8), 152.1 (C14), 151.2 (C-6), 139.7 (C-7), 130.1 (C-13), 129.5 (C-4), 126.7 (C-5), 121.2 (C-9), 102.4 (C-2), 59.5 (C-15), 51.8 (C-12), 43.7 (C-10), 32.4 (C-11). HRMS-ESI-IT-TOF: m/z calculated C15H17ClN5O 317.10, found 317.05.

2-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)ethan-1-ol(11a)

Yellow powder. m.p. 148.3-152.6 ºC, IR (λmax, cm-1): 3277, 3138, 2955, 2924, 2384, 2349, 2307, 1585, 1456, 1049, 810. 1H NMR (200 MHz, MeOD): δ8.33 (d, 1H, J = 5.0, H-2), 7.97 (d, 1H, J = 8.8, H-5), 7.75 (sl, 2H, H-8 e H-13), 7.38 (dd, 1H, J = 1.4 e 8.8, H-6), 6.49 (d, 1H, J = 5.2, H-3), 4.68 (t, 2H, J = 5.6, H-12), 3.90 (t, 2H, J = 5.2, H-16), 3.73 (t, 2H, J = 6.8, H-11), 2.84 (t, 2H, J = 6.6, H-15). 13C NMR (50 MHz, MeOD): δ152.6 (C-3), 151.8 (C-2), 148.9 (C-8), 146.4 (C-13), 136.8 (C-6), 127.1 (C-7), 126.5 (C-4), 124.7 (C-12), 124.3 (C-5), 118.6 (C-9), 99.6 (C-2), 62.0 (C-15), 49.7 (C-11), 43.1 (C-10), 29.8 (C-14). HRMS-ESI-IT-TOF: m/z calculated C15H17ClN5O 317.10, found 317.10.

2-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)ethan-1-ol(11b)

Yellow powder. m.p. 90.1-93.2 ºC, IR (λmax, cm-1): 3273, 3127, 2955, 2928, 2388, 2353, 2307, 1593, 1456, 745. 1H NMR (200 MHz, MeOD): δ8.40-8.31 (m, 2H, H-2 e H-5), 7.94 (s, 1H, H-14), 7.87 (d, 1H, J = 1.6, H-8), 7.66 (dd, 1H, J = 1.8 e 9.2, H-6), 6.83 (d, 1H, J = 7.2, H-3), 4.60 (t, 2H, J = 6.6, H-13), 3.84-3.74 (m, 2H, H-17), 3.67 (t, 2H, J = 6.8, H-11) 2.86 (sl, 2H, H-16), 2.43 (q, 2H, J = 6.4 e 13, H-12). 13C NMR (100 MHz, CDCl3): δ157.6 (C-3), 143.9 (C-13), 141.0 (C-8), 140.0 (C-6), 128.7 (C-7), 126.0 (C-4), 120.3 (C-5), 116.9 (C-9), 99.8 (C-2), 61.8 (C-16), 47.7 (C-12), 42.1 (C-10), 29.6 (C-15), 28.7 (C-11). HRMS-ESI-IT-TOF: m/z calculated C16H19ClN5O 331.12, found 331.10.

3-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)propan-1-ol(12a)

White powder. m.p. 65.2-68.0 ºC, IR (λmax, cm-1): 3285, 2944, 2881, 1610, 1581, 1548. 1H NMR (400 MHz, MeOD): δ8.33 (d, 1H, J = 5.2, H-2), 7.99 (d, 1H, J = 8.8, H-5), 7.77 (sl, 1H, H-8), 7.69 (s, 1H, H-13), 7.41 (dd, 1H, J = 1.6 e 9.6, H-6), 6.47 (d, 1H, J = 5.6, H-3), 4.87 (t, 2H, J = 5.2, H-12), 3.91 (t, 2H, J = 5.2, H-11), 3.50 (t, 2H, J = 6, H-17), 2.69 (t, 2H, J = 7.2, H-15), 1.76 (q, 2H, J = 6.4 e 13.6, H-16). 13C NMR (50 MHz, DMSO-d6): δ151.7 (C-2), 149.6 (C-3), 148.8 (C-8), 146.6 (C-13), 133.4 (C-6), 127.4 (C-7), 124.3 (C-5), 123.8 (C-4), 122.2 (C-12), 117.3 (C-9), 98.7 (C-2), 59.9 (C-16), 47.6 (C-11), 42.3 (C-10), 32.2 (C14), 21.5 (C-15).

3-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)propan-1-ol(12b)

White powder. m.p. 140.0-142.5 ºC, IR (λmax, cm-1): 3289, 3150, 2909, 2862, 1612, 1583, 1490. 1H NMR (200 MHz, DMSO-d6): δ8.38 (d, 1H, J = 5.4, H-2), 8.25 (d, 1H, J = 9.2, H-5), 7.88 (s, 1H, H-14), 7.78 (d, 1H, J = 2.2, H-8), 7.45 (dd, 1H, J = 2.2 e 9.0, H-6), 6.42 (d, 1H, J = 5.4, H-3), 4.44 (t, 2H, J = 6.8, H-13), 3.26 (t, 2H, J = 6.6, H-11), 2.63 (t, 2H,J = 7.4, H-16), 2.19 (q, 2H, J = 7.0 e 13.8, H-12), 1.72 (q, 2H, J = 6.6 e 14.4, H-17). 13C NMR (50 MHz, DMSO-d6): δ151.8 (C-2), 149.8 (C-3), 148.9 (C-8), 146.7 (C-14), 133.3 (C-6), 127.4 (C-7), 124.0 (C-4), 124.0 (C-13), 121.8 (C-5), 117.4 (C-9), 98.6 (C-2), 59.9 (C-17), 47.1 (C-12), 39.5 (C-10), 32.2 (C-15), 28.4 (C-16), 21.6 (C-11).

1-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)propan-1-ol(13a)

White powder. m.p. 208.1-209.0 ºC, IR (λmax, cm-1): 3725, 3698, 3630, 2386, 2367, 2351, 2299, 1582, 673. 1H NMR (300 MHz, MeOD): d 8.47 (d, 1H, J1-2 = 5.26, H-1), 7.94-7.97 (m, 2H, H-7 and H-13), 7.73 (s, 1H, H-4), 7.447.52 (m, 1H, H-5), 6.48 (d, 1H, J1-2 = 5.24, H-2), 4.35-4.50 (m, 5H, H-11, H-11’, H-15, -NH and -OH), 3.97 (d, 2H, J10-10’ = 4.79, H-10 and H-10’), 1.89-1.94 (m, 2H, -CH2-), 1.00-1.02 (m, 3H, -CH3). 13C NMR (100 MHz, CDCl3): δ155.7 (C-3), 155.1 (C-1), 154.1 (C-8), 152.2 (C-14), 139.4 (C-6), 131.0 (C-7), 129.5 (C-13), 126.2 (C-4), 126.0 (C5), 121.2(C-9), 102.3 (C-2), 71.7 (C-15), 52.4 (C-11), 46.5 (C-10), 34.0 (C-16), 13.4 (C-17).HRMS-ESI-IT-TOF: m/z calculated C16H19ClN5O 331.12, found331.10.

1-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)propan-1-ol(13b)

White powder. m.p. 195.5-197.9 ºC, IR (λmax, cm-1): 2959, 2920, 2855, 2378, 2347, 2309, 1728, 1582, 1464, 1267, 748. 1H NMR (300 MHz, MeOD): δ9.32 (d, 1H, J1-2 = 5.64 Hz, H-1), 9.00 (d, 1H, J4-5= 9.02 Hz, H-4), 8.76-8.79 (m, 2H, H-7 and H-13), 8.49 (s, 1H, -NH), 8.37-8.40 (m, 1H, H-5), 7.39 (d, 1H, J2-1 = 5.73 Hz, H-2), 5.66-5-69 (m, 3H, -CH3), 5.51-5.54 (m, 2H, H-16 and H-16’), 4.32-4.40 (m, 2H, H-12 and H-12’), 4.31 (s, 1H, -OH), 3.30-3.36 (m, 2H, H-10 and H-10’), 3.19 (s, 1H, H-11’), 2.26-2.30 (m, 1H, H-11), 0.93-0.96 (m, 1H, H-15). 13C NMR (100 MHz, CDCl3): δ155.1 (C-3), 154.4 (C-1), 152.0 (C-8), 151.5 (C-14), 139.6 (C-6), 130.3 (C-7), 129.4 (C-13), 126.7 (C-4), 126.6 (C-5), 121.2(C-9), 102.4 (C-2), 81.3 (C-15),59.4 (C-12), 43.7 (C-11), 36.6 (C-10), 32.4 (C-16), 13.1 (C-17).HRMS-ESIIT-TOF: m/z calculated C17H21ClN5O 345.14, found345.10.

2-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)propan-2-ol (14a)

White powder. m.p. 180.2-183.0 ºC, IR (λmax, cm-1): 3354, 3146, 2984, 2928, 1610, 1579, 1486, 1455. 1H NMR (200 MHz, DMSO-d6): δ8.38 (d, 1H, J = 5.4, H-2), 8.18 (d, 1H, J = 9.0, H-5), 7.90 (s, 1H, H-13), 7.80 (d, 1H, J = 2.2, H-8), 7.47 (dd, 1H, J = 2.2 e 9.0, H-6), 6.49 (d, 1H, J = 5.4, H-3), 4.60 (t, 2H, J = 6.2, H-12), 3.78-3.75 (m, 2H, H-11), 1.40 (s, 6H, H-16). 13C NMR (50 MHz, DMSO-d6): δ155.7 (C-3),151.8 (C-2), 149.7 (C-8), 148.9 (C-13), 133.4 (C-6), 127.4 (C-7), 124.3 (C-4), 123.8 (C-12), 121.0 (C-5), 117.3 (C-9), 98.7 (C-2), 66.9 (C-14), 47.6 (C-11), 42.43 (C10), 30.6 (C-15).

2-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)propan-2-ol (14b)

White powder. m.p. 149.7-151.7 ºC, IR (λmax, cm-1): 3354, 3146, 2984, 2928, 1610, 1579, 1486, 1455. 1H NMR (200 MHz, DMSO-d6): δ8.38 (d, 1H, J = 5.4, H-2), 8.18 (d, 1H, J = 9.0, H-5), 7.90 (s, 1H, H-13), 7.80 (d, 1H, J = 2.2, H-8), 7.47 (dd, 1H, J = 2.2 e 9.0, H-6), 6.49 (d, 1H, J = 5.4, H-3), 4.60 (t, 2H, J = 6.2, H-12), 3.78-3.75 (m, 2H, H-11), 1.40 (s, 6H, H-16). 13C NMR (50 MHz, DMSO-d6): δ155.7 (C-3),151.8 (C-2), 149.7 (C-8), 148.9 (C-13), 133.4 (C-6), 127.4 (C-7), 124.3 (C-4), 123.8 (C-12), 121.0 (C-5), 117.3 (C-9), 98.7 (C-2), 66.9 (C-14), 47.6 (C-11), 42.43 (C10), 30.6 (C-15).

N-(2-(4-(aminomethyl)-1H-1,2,3-triazol-1-yl) ethyl)-7-chloroquinolin-4-amine (15a)

Redish powder.m.p. 233.0-235.3 ºC, IR (λmax, cm-1): 3300, 3134, 2963, 2878, 2388, 2347, 2305, 1578, 1144, 1053, 810. 1H NMR (300 MHz, MeOD): d 8.45 (d, 1H, H-1), 8.02-8.06 (m, 1H, H-4), 7.94 (s, 1H, H-7), 7.75-7.76 (m, 1H, H-13), 7.50 (d, 1H, H-2), 6.48-6.51 (m, 1H, H-5), 4.00 (s, 2H, -NH2), 1.64-2.08 (m, 6H, H-11, H-11’, H-15, H-15’, H-10 and H-10’), 1.32 (s, 1H, -NH). 13C NMR (100 MHz, CDCl3): δ155.2 (C-3), 150.2 (C-1), 148.2 (C-8), 135.4(C-14), 127.9 (C-6), 126.9 (C-7), 125.5 (C-13), 124.9 (C-4), 122.2 (C-5), 117.2 (C-9), 98.2 (C-2), 71.4 (C-11), 42.4 (C-10), 29.6 (C-15). HRMS-ESI-IT-TOF: m/z calculated C14H16ClN6302.10, found 302.10.

N-(3-(4-(aminomethyl)-1H-1,2,3-triazol-1-yl) propyl)-7-chloroquinolin-4-amine (15b)

Brown oil. IR (λmax, cm-1): 3296, 3065, 2955, 2388, 2347, 2309, 1582, 1456, 1140, 802, 737. 1H NMR (300 MHz, MeOD): δ8.62-8.65 (m, 2H, -NH2), 8.39-8.46 (m, 2H, H-4 and H-7), 8.07-8.22 (m, 3H, H-1, H-13 and -NH), 7.67-7.72 (m, 2H, H-5 and H-2), 3.69-3.72 (m, 2H, H-12 and H-12’), 3.57 (s, 1H, H-11’), 3.24-3.30 (m, 1H, H-11), 2.89 (s, 1H, H-15’), 2.60-2.70 (m, 2H, H-10 and H-10’), 1.551.58 (m, 1H, H-15). 13C NMR (100 MHz, CDCl3): δ155.4 (C-3), 154.7 (C-1), 148.9 (C-8), 139.3 (C-14), 130.2 (C-6), 129.1 (C-7), 128.5 (C-13), 127.6 (C-4), 127.5 (C-5), 121.4 (C-9), 102.6 (C-2), 49.1 (C-15), 46.2 (C-12), 32.6 (C-11), 30.7 (C-10). HRMS-ESI-IT-TOF: m/z calculatedC15H18ClN6 (M+H) 317.7966, found 317.3698.

7-chloro-N-(2-(4-((methylamino)methyl)-1H-1,2,3triazol-1-yl)ethyl)quinolin-4-amine (16a)

Brown oil. IR (λmax, cm-1): 3308, 2951, 2382, 2344, 2317, 1578, 1452, 1144, 1053, 806. 1H NMR (300 MHz, MeOD): δ8.45 (s, 1H, H-1), 7.89-8.01 (m, 2H, H-4 and H-7), 7.39 (s, 1H, H-13), 6.46 (s, 2H, H-2 and H-5), 3.96 (s, 3H, -CH3), 3.50 (s, 1H, -NH), 2.99 (s, 2H, H-11 and H-11’), 2.55 (s, 2H, H-15 and H-15’), 2.05 (s, 1H, -NH), 1.21-1.38 (m, 2H, H-10 and H-10’). 13C NMR (100 MHz, CDCl3): δ154.8 (C-3), 154.4(C-1), 151.8 (C-8), 147.6 (C-14), 139.4 (C-6), 130.7 (C-7), 129.4 (C-13), 128.1 (C-4), 126.6 (C-5), 121.2(C-9), 102.2 (C-2), 49.7 (C-11), 48.9 (C-15), 46.5 (C-10), 38.3 (C-16).

7-chloro-N-(3-(4-((methylamino)methyl)-1H-1,2,3triazol-1-yl)propyl)quinolin-4-amine (16b)

Brown oil. IR (λmax, cm-1): 3317, 3141, 2958, 2882, 2363, 2344, 1585, 1451, 1367, 1138, 1054, 806. 1H NMR (300 MHz, MeOD): d 9.54 (d, 1H, J1-2 = 6.69 Hz, H-1), 8.97-9.12 (m, 3H, H-4, H-7 and H-13), 8.52 (d, 1H, H-5), 7.52 (d, 1H, J2-1 = 5.96 Hz, H-2), 5.07 (s, 2H, H-15 and H-15’), 4.52-4.56 (m, 2H, H-12 and H-12’), 4.04-4.09 (m, 3H, -CH3), 3.66 (s, 1H, -NH), 3.47-3.52 (m, 2H, H-10 and H-10’), 3.13 (s, 1H, -NH), 2.35-2.45 (m, 2H, H-11 and H-11’). 13C NMR (100 MHz, CDCl3): δ150.8 (C-3), 147.9(C1), 144.3 (C-8), 135.4 (C-14), 131.2 (C-6), 127.0 (C-7), 125.5 (C-13), 123.5 (C-4), 122.3 (C-5), 117.2(C-9), 98.5 (C-2), 47.9 (C-11), 45.4 (C-15), 39.6 (C-12), 34.8 (C-10), 28.2 (C-16).

7-chloro-N-(2-(5-((dimethylamino)methyl)-1H-1,2,3-triazol-1-yl)ethyl)quinolin-4-amine (17a)

Brown oil. IR (λmax, cm-1): 3273, 3092, 2970, 2946, 2759, 2706, 2363, 2340, 1585, 1458, 1241, 852. 1H NMR (300 MHz, MeOD): d 9.05 (d, 1H, J1-2 = 5.55 Hz, H-1), 8.52-8.56 (m, 2H, H-4 and H-5), 8.32 (s, 1H, H-7), 8.02-8.06 (m, 1H, H-13), 7.07 (d, 1H, J2-1 = 5.43 Hz, H-2), 5.355.38 (m, 2H, H-15 and H-15’), 4.54-4.57 (m, 2H, H-11 and H-11’), 4.23-4.28 (m, 2H, H-10 and H-10’), 2.89 (s, 6H, 2 CH3), 1.96 (s, 1H, -NH). 13C NMR (100 MHz, CDCl3): δ155.1 (C-3), 154.2 (C-1), 152.2 (C-8), 147.8 (C-14), 139.5 (C-6), 131.1 (C-7), 129.6 (C-13), 128.2 (C-4), 126.1 (C-5), 121.2 (C-9), 102.3 (C-2), 67.3 (C-15), 57.6 (C-10), 48.5 (C16, C-16’), 46.5 (C-11). HRMS-ESI-IT-TOF: m/z calculated C16H20ClN6 330.14, found 330.15.

7-chloro-N-(3-(4-((dimethylamino)methyl)-1H-1,2,3-triazol-1-yl)propyl)quinolin-4-amine (17b)

Brown oil. IR (λmax, cm-1): 3377, 3123, 3065, 3034, 2990, 2955, 2689, 2378, 2355, 2309, 1582, 1456, 806. 1H NMR (300 MHz, MeOD): d 8.84 (d, 1H, J1-2 = 10.55 Hz, H-1), 8.70-8.72 (m, 2H, H-4 and H-5), 8.26 (s, 1H, H-7), 7.86 (s, 1H, H-13), 7.00 (d, 1H, J2-1 = 6.84 Hz, H-2), 5.64 (s, 1H, -NH), 4.52 (s, 2H, H-15 and H-15’), 3.96-3.98 (m, 2H, H-12 and H-12’), 3.55-3.58 (m, 2H, H-10 and H-10’), 3.06 (s, 6H, 2 CH3), 2.85-2.87 (m, 2H, H-11 and H-11’). 13C NMR (100 MHz, CDCl3): δ154.7 (C-3), 144.1(C-1), 140.4 (C-8), 139.3 (C-14), 138.6 (C-6), 127.0 (C-7), 126.3 (C13), 124.7 (C-4), 120.8 (C-5), 115.8(C-9), 98.2 (C-2), 62.5 (C-15), 46.1 (C-12), 43.1 (C-16, C-16’), 40.4 (C-10), 28.1 (C-11). HRMS-ESI-IT-TOF: m/z calculatedC17H22ClN6 (M+H) 345.85, found 345.40.

1-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)cyclopentan-1-ol (18a)

Yellow powder. m.p. 227.6-230.2 ºC, IR (λmax, cm-1): 3386, 3196, 3107, 3054, 3002, 2945, 9861, 2364, 2340, 1587, 1451, 1337, 1163, 803. 1H NMR (400 MHz, CDCl3): δ8.31-8.27 (m, 2H, H-2 e H-5), 7.90 (s, 1H, H-13), 7.87 (d, 1H, J = 1.6, H-8), 7.65 (dd, 1H, J = 2.0 e 8.8, H-6), 6.63 (d, 1H, J = 7.2, H-3), 4.79 (t, 2H, J = 5.6, H-12), 4.14 (t, 2H, J = 5.6, H-11), 1.97-1.73 (m, 8H, H-16, H-17, H-18 e H-19). 13C NMR (100 MHz, MeOD): δ158.0 (C-3), 144.0 (C-1), 141.2 (C-6), 140.0 (C-13), 129.0 (C-7), 125.8 (C-4), 123.7 (C-5), 120.4 (C-5), 116.9 (C-9), 99.4 (C-2), 79.4 (C14), 49.8 (C-11), 44.4 (C-10), 41.9 (C-15), 37.5 (C-18), 24.4 (C-16), 23.9 (C-17).

1-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)cyclopentan-1-ol (18b)

Yellow powder. m.p. 180.2-183.0 ºC, IR (λmax, cm-1): 3728, 3694, 2659, 2928, 2853, 2386, 2361, 2295, 1541, 1194. 1H NMR (200 MHz, CDCl3): δ8.31-8.27 (m, 2H, H-2 e H-5), 7.90 (s, 1H, H-13), 7.87 (d, 1H, J = 1.6, H-8), 7.65 (dd, 1H, J = 2.0 e 8.8, H-6), 6.63 (d, 1H, J = 7.2, H-3), 4.79 (t, 2H, J = 5.6, H-12), 4.14 (t, 2H, J = 5.6, H-11), 1.97-1.73 (m, 8H, H-16, H-17, H-18 e H-19). 13C NMR (100 MHz, MeOD): δ158.0 (C-3), 144.0 (C-1), 141.2 (C-6), 140.0 (C13), 129.0 (C-7), 125.8 (C-4), 123.7 (C-5), 120.4 (C-5), 116.9 (C-9), 99.4 (C-2), 79.4 (C-14), 49.8 (C-11), 44.4 (C-10), 41.9 (C-15), 37.5 (C-18), 24.4 (C-16), 23.9 (C-17).

7-chloro-N-(2-(4-cyclohexyl-1H-1,2,3-triazol-1-yl)ethyl)quinolin-4-amine (19a)

Yellowish powder. m.p. 215.3-217.9 ºC, IR (λmax, cm1): 3277, 3142, 2886, 2806, 1619, 1580, 1426. 1H NMR (200 MHz, MeOD): δ8.33 (d, 1H, J = 7.0, H-2), 8.27 (d, 1H, J = 9.2, H-5), 7.88 (d, 1H, J = 1.8, H-8), 7.85 (s, 1H, H-13), 7.69 (dd, 1H, J = 2.0 e 9.2, H-6), 6.68 (d, 1H, J = 7.2, H-3), 4.79 (t, 2H, J = 5.2, H-12), 4.14 (t, 2H, J = 5.4, H-11), 1.911.73 (m, 6H, H-15, H-16, H-17 e H-18), 1.42-1.27 (m, 5H, H-15, H-16, H-17 e H-18). 13C NMR (50 MHz, DMSO-d6): δ151.9 (C-3), 151.7 (C-1), 149.6 (C-8), 148.9 (C-13), 133.4 (C-6), 127.4 (C-7), 124.2 (C-5), 123.8 (C-4), 121.0 (C-12), 117.4 (C-9), 98.7 (C-2), 47.7 (C-11), 42.3 (C-10), 34.4 (C14), 32.4 (C-15), 25.5 (C-17), 25.4 (C-16).

7-chloro-N-(3-(4-cyclohexyl-1H-1,2,3-triazol-1-yl)propyl)quinolin-4-amine (19b)

Yellowpowder. m.p. 136.1-138.9 ºC, IR (λmax, cm-1): 3283 e 3115 (N-H); 3060 (C-H aromático); 2927, 2853, 1608, 1582, 1446. 1H NMR (200 MHz, MeOD): δ8.17 (d, 1H, J = 5.6, H-2), 7.86 (d, 1H, J = 9.2, H-5), 7.61 (d, 1H, J = 2.0, H-8), 7.56 (s, 1H, H-14), 7.21 (dd, 1H, J = 2.0 e 9.0, H-6), 6.27 (d, 1H, J = 5.6, H-3), 4.40 (t, 2H, J = 6.6, H-13), 3.27-3.25 (m, 2H, H-11), 2.20 (q, 2H, J = 6.4 e 13.2, H-12), 1.80-1.60 (m, 5H, H-16 e H-17), 1.27-1.07 (m, 6H, H-18 e H-19). 13C NMR (50 MHz, MeOD): δ154.5 (C-3), 152.4 (C-8), 152.2 (C-1), 149.3 (C-14), 136.3 (C-6), 127.4 (C-7), 126.0 (C-4), 124.3 (C-5), 122.0 (C-13), 118.6 (C-9), 99.5 (C-2), 49.2 (C-12), 41.2 (C-10), 36.3 (C-15), 33.9 (C16), 29.6 (C-11), 27.1 (C-17), 27.0 (C-18).

1-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)cyclohexan-1-ol (20a)

White powder. m.p. 191.0-193.0 ºC, IR (λmax, cm-1): 3386, 3196, 3111, 3047, 2998, 2942, 2861, 2368, 2340, 1584, 1535, 1447, 1337, 1163, 807. 1H NMR (200 MHz, CDCl3): δ8.29 (d, 1H, J = 6.8, H-2), 8.28 (d, 1H, J = 8.8, H-5), 7.89 (s, 1H, H-13), 7.87 (d, 1H, J = 1.6, H-8), 7.67 (dd, 1H, J = 1.6 e 8.8, H-6), 6.62 (d, 1H, J = 7.2, H-3), 4.79 (t, 2H, J = 5.2, H-12), 4.15 (t, 2H, J = 5.2, H-11), 1.931.52 (m, 10H, H-16, H-17, H-18, H-19 e H-20). 13C NMR (50 MHz, MeOD): δ160.8 (C-3), 158.0 (C-8), 144.0 (C-1), 141.2 (C-6), 140.0 (C-13), 129.0 (C-7), 125.8 (C-4), 123.7 (C-12), 120.4 (C-5), 116.9 (C-9), 99.4 (C-2), 73.0 (C-14), 49.4 (C-11), 44.4 (C-10), 40.8 (C-15), 38.8 (C-19), 26.4 (C-17), 24.2 (C-16), 23.0 (C-18).

1-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)cyclohexan-1-ol (20b)

Yellowish powder. m.p. 149.7-151.7 ºC, IR (λmax, cm1): 3726, 3127, 2932, 2855, 2382, 2355, 2301, 1570, 1368, 845, 669. 1H NMR (200 MHz, CDCl3): δ8.29 (d, 1H, J = 6.8, H-2), 8.28 (d, 1H, J = 8.8, H-5), 7.89 (s, 1H, H-13), 7.87 (d, 1H, J = 1.6, H-8), 7.67 (dd, 1H, J = 1.6 e 8.8, H-6), 6.62 (d, 1H, J = 7.2, H-3), 4.79 (t, 2H, J = 5.2, H-12), 4.15 (t, 2H, J = 5.2, H-11), 1.93-1.52 (m, 10H, H-16, H-17, H-18, H-19 e H-20). 13C NMR (50 MHz, MeOD): δ160.8 (C-3), 158.0 (C-8), 144.0 (C-1), 141.2 (C-6), 140.0 (C-13), 129.0 (C-7), 125.8 (C-4), 123.7 (C-12), 120.4 (C-5), 116.9 (C9), 99.4 (C-2), 73.0 (C-14), 49.4 (C-11), 44.4 (C-10), 40.8 (C-15), 38.8 (C-19), 26.4 (C-17), 24.2 (C-16), 23.0 (C-18).

7-chloro-N-(2-(4-phenyl-1H-1,2,3-triazol-1-yl)ethyl)quinolin-4-amine (21a)

Yellowish powder. m.p. 268.0-271.0 ºC, IR (λmax, cm1): 3306, 3007, 1611, 1585, 1543, 1450, 1436. 1H NMR (200 MHz, CDCl3): δ8.58 (s, 1H, H-13), 8.55 (sl, 1H, H-2), 8.41 (d, 1H, J = 9.2, H-5), 7.92 (d, 1H, J = 1.8, H-8), 7.79-7.73 (m, 3H, H-6 e H-16), 7.44-7.25 (m, 3H, H17 e H-18), 6.93 (d, 1H, J = 7.2, H-3), 4.75 (t, 2H, J = 5.2, H-12), 4.11 (t, 2H, J = 4.8, H-11). 13C NMR (100 MHz, MeOD): δ156.4 (C-3), 151.6 (C-1), 148.8 (C-8), 136.2 (C-14), 127.4 (C-7), 126.2 (C-13), 123.1 (C-15), 118.0 (C-7), 98.9 (C-17), 69.8 (C-16), 43.2 (C-4), 40.1 (C-5), 38.2 (C-9), 25.9 (C-2), 23.7 (C-11), 22.4 (C-10). HRMS-ESI-IT-TOF: m/z calculated C19H17ClN5 349.11, found 349.10.

7-chloro-N-(3-(4-phenyl-1H-1,2,3-triazol-1-yl)propyl)quinolin-4-amine (21b)

Yellowish powder. m.p. 222.8-225.9 ºC, IR (λmax, cm1): 3327, 3057, 3023, 2944, 2893, 1611, 1579, 1541, 1444. 1H NMR (200 MHz, MeOD): δ8.18 (d, 1H, J = 7.4, H-2), 8.14 (s, 1H, H-14), 8.02 (d, 1H, J = 9.2, H-5), 7.57 (d, 1H, J = 2.0, H-8), 7.46 (dd, 2H, J = 1.8 e 8.2, H-18), 7.36 (dd, 1H, J = 2.0 e 9.2, H-6), 7.27-7.16 (m, 3H, H-17 e H-19), 6.67 (d, 1H, J = 7.2, H-3), 4.50 (t, 2H, J = 6.2, H-13), 3.58 (t, 2H, J = 6.6, H-11), 2.35 (q, 2H, J = 6.6 e 13.0, H-12). 13C NMR (50 MHz, DMSO-d6): δ151.8 (C-1), 149.9 (C-3), 148.9 (C-8), 146.2 (C-14), 133.3 (C-6), 130.7 (C-15), 128.8 (C-17), 127.7 (C-18), 127.4 (C-13), 125.0 (C-16), 124.0 (C7), 124.0 (C-4), 121.4 (C-5), 117.4 (C-9), 98.7 (C-2), 47.5 (C-12), 39.5 (C-10), 28.3 (C-11). HRMS-ESI-IT-TOF: m/z calculated C20H19ClN5 (M+H) 364.85, found 364.35.

1-(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)-1-phenylethan-1-ol (22a)

White powder. m.p. 225.0-227.5 ºC, IR (λmax, cm-1): 3277, 3119, 2955, 2924, 2384, 2349, 2307, 1585, 1456, 1019, 810, 745. 1H NMR (300 MHz, MeOD): d 8.72 (d, 1H, J1-2 = 7.12 Hz, H-1), 8.23-8.27 (m, 2H, H-4 and H-7), 7.84 (d, 1H, J2-1 = 10.75 Hz, H-2), 7.72-7.78 (m, 3H, H-5, H-17, H-17’), 7.60-7.63 (m, 3H, H-18, H-18’, -NH), 6.73-6.75 (m, 1H, H-13), 5.00-5.05 (m, 2H, H-11 and H-11’), 4.22-4.27 (m, 2H, H-10 and H-10’), 2.29-2.31 (m, 3H, -CH3), 1.65 (s, 1H, -OH). 13C NMR (100 MHz, CDCl3): δ159.3 (C-3), 155.0 (C-1), 154.3 (C-8), 152.2 (C-17), 150.4 (C-6), 139.5 (C-14), 131.9 (C-7), 131.0 (C-19, C-19’), 130.9 (C-20), 129.5 (C-18, C-18’), 128.9 (C-4), 126.3 (C-13), 126.2 (C-5), 121.2 (C9), 102.2 (C-2), 75.4 (C-15), 52.5 (C-11), 46.4 (C-10), 33.6 (C-16). HRMS-ESI-IT-TOF: m/z calculated C21H21ClN5O (M+H) 394.88, found 394.20.

1-(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)-1-phenylethan-1-ol(22b)

Yellowish powder. m.p. 65.7-69.6 ºC, IR (λmax, cm-1): 3294, 2982, 1748, 1666, 1584, 1538, 1447, 1371, 1219, 1138. 1H NMR (300 MHz, MeOD): δ8.37 (s, 1H, H-1), 8.05-8.07 (m, 2H, H-4 and H-7), 7.82-7.88 (m, 3H, H-5, H-13 and -NH), 7.63-7.78 (m, 6H, -Ar and H-2), 3.76-3.80 (m, 3H, -CH3), 3.40 (s, 1H, H-11’), 3.29 (s, 1H, H-11), 2.73 (s, 2H, H-12 and H-12’), 2.38 (s, 2H, H-10 and H-10’), 2.17 (s, 1H, -OH). 13C NMR (100 MHz, MeOD): δ163.7 (C-3), 147.2 (C-1), 145.8 (C-8), 135.9 (C-17), 128.5 (C-6), 127.9 (C-14), 127.5 (C-7), 126.1 (C-19, C-19’), 125.6 (C-20), 125.3 (C-18, C-18’), 72.8 (C-4), 69.5 (C-13), 50.0 (C-5), 46.4 (C-9), 40.2 (C-2), 37.1 (C-15), 33.5 (C-12), 31.8 (C-11), 31.1 (C-10), 28.7 (C-16). HRMS-ESI-IT-TOF: m/z calculated C22H23ClN5O 407.15, found 407.25.

(1-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-1,2,3-triazol-4-yl)(phenyl)methanol (23a)

Yellowish powder. m.p. 238.3-240.0 ºC, IR (λmax, cm-1): 3119, 2384, 2349, 2307, 2924, 1585, 1456, 810, 749. 1H NMR (300 MHz, MeOD): d 9.02 (d, 1H, J1-2 = 4.92 Hz, H-1), 8.49-8.53 (m, 2H, H-4 and H-7), 7.91-8.07 (m, 7H, H-13, H-5, H-17, H-17’, H-18, H-18’ and H-19), 7.04 (d, 1H, J2-1 = 5.31 Hz, H-2), 6.58 (s, 1H, -NH), 5.28-5.31 (m, 2H, H-11 and H-11’), 4.49-4.52 (m, 2H, H-10, H-10’), 2.86 (s, 1H, -OH), 1.81-1.85 (m, 1H, H-15). 13C NMR (100 MHz, CDCl3): δ155.7(C-3), 155.1 (C-1), 154.0 (C-8), 152.3 (C-17), 146.0 (C-6), 139.4 (C14), 132.3 (C-7), 131.7 (C-19, C-19’), 131.2 (C-20), 130.0 (C-18, C-18’), 129.6 (C-4), 126.6 (C-13), 126.0 (C-5), 121.2 (C-9), 102.3 (C-2), 72.4 (C-15), 52.4 (C-11), 46.4 (C-10). HRMS-ESI-IT-TOF: m/z calculated C20H19ClN5O (M+H) 380.85, found 380.35.

(1-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-1,2,3-triazol-4-yl)(phenyl)methanol (23b)

Yellowish powder. m.p. 160.2-162.7 ºC, IR (λmax, cm-1): 3361, 3307, 2955, 2921, 2851, 2361, 2341, 1585, 1455, 1048, 853, 670. 1H NMR (300 MHz, MeOD): d 9.32-9.34 (m, 1H, H-4), 8.93 (d, 1H, J1-2 = 8.57 Hz, H-1), 8.84 (s, 1H, H-7), 8.51 (s, 1H, H-13), 8.28-8.42 (m, 7H, H-5, H-17, H-17’, H-18, H-18, H-19 and -NH), 7.33 (d, 1H, J2-1 = 5.25, H-2), 6.96 (s, 1H, -OH), 5.44-5.48 (m, 1H, H-15), 4.35-4.39 (m, 2H, H-12 and H-12’), 3.27-3.33 (m, 2H, H-10 and H-10’), 2.26-2.34 (m, 2H, H-11 and H-11’). 13C NMR (100 MHz, CDCl3): δ151.9 (C-3), 150.9 (C-1), 150.2 (C-8), 147.2 (C-17), 142.1 (C-6), 135.8 (C14), 128.5 (C-7), 127.8 (C-19, C-19’), 126.4 (C-20), 126.3 (C-18, C-18’), 125.6 (C-4), 122.1 (C-13), 117.0 (C-5), 98.4 (C-2), 68.6 (C-15), 47.8 (C-11), 39.6 (C-10). HRMS-ESIIT-TOF: m/z calculated C21H21ClN5O (M+H) 394.88, found 394.34.

7-chloro-N-(2-(4-(p-tolyl)-1H-1,2,3-triazol-1-yl)ethyl)quinolin-4-amine (24a)

Yellowish powder. m.p. 276.8-278.2 ºC, IR (λmax, cm-1): 3303, 3142, 2922, 1608, 1579, 1498, 1443. 1H NMR (400 MHz, DMSO-d6): δ8.58 (d, 1H, J = 6.8, H-2), 8.56 (s, 1H, H-13), 8.42 (d, 1H, J = 9.2, H-5), 7.96 (d, 1H, J = 1.6, H-8), 7.79 (dd, 1H, J = 1.6 e 9.2, H-6), 7.64 (d, 2H, J = 8, H-16), 7.22 (d, 2H, J = 8, H-17), 6.94 (d, 1H, J = 7.2, H-3), 4.74 (t, 2H, J = 5.6, H-12), 4.09 (t, 2H, J= 5.2, H-11), 2.30 (s, 3H, H-19). 13C NMR (100 MHz, DMSO-d6): δ155.5 (C-3), 146.4 (C-8), 143.3 (C-1), 138.6 (C-13), 138.0 (C-6), 137.1 (C-17), 129.3 (C-16), 127.8 (C-14), 127.0 (C-12), 125.2 (C-7), 124.9 (C-15), 121.5 (C-4), 119.3 (C-5), 115.4 (C-9), 98.6 (C-2), 47.7 (C-11), 42.8 (C-10), 20.7 (C-18).

7-chloro-N-(3-(4-(p-tolyl)-1H-1,2,3-triazol-1-yl)propyl)quinolin-4-amine (24b)

Yellow powder. m.p. 237.8-238.4 ºC, IR (λmax, cm-1): 3263, 3024, 2771, 1612, 1594, 1568, 1498, 1453. 1H NMR (400 MHz, CDCl3): δ8.26 (d, 1H, J = 7.0, H-2), 8.22 (s, 1H, H-14), 8.11 (d, 1H, J = 9.0, H-5), 7.66 (d, 1H, J = 1.8, H-8), 7.44 - 7.39 (m, 3H, H-6 e H-17), 7.13 (d, 2H, J = 8, H-18), 6.75 (d, 1H, J = 7.2, H-3), 4.62 (t, 2H, J = 6.2, H-13), 3.69 (t, 2H, J = 6.8, H-11), 2.47 (q, 2H, J = 6.0 e 12.2, H-12), 2.31 (s, 3H, H-20). 13C NMR (100 MHz, MeOD): δ157.2 (C-3), 148.7 (C-8), 143.6 (C-1), 140.8 (C-14), 139.7 (C-6), 130.5 (C-17), 128.6 (C-13), 128.0 (C-18), 126.3 (C-16), 125.7 (C-7), 122.4 (C-4), 120.1 (C-5), 116.7 (C-15), 114.0 (C-9), 99.6 (C-2), 49.6 (C-12), 42.4 (C-10), 28.8 (C-11), 21.3 (C-19).

7-chloro-N-(2-(4-(4-methoxyphenyl)-1H-1,2,3triazol-1-yl)ethyl)quinolin-4-amine (25a)

Yellowish powder. m.p. 234.3-237.0 ºC, IR (λmax, cm-1): 3295, 2999, 2936, 2834, 1618, 1580, 1498, 1460, 1220, 1162. 1H NMR (200 MHz, DMSO-d6): δ8.47 (s, 1H, H-13), 8.42 (d, 1H, J = 5.2, H-2), 8.16 (d, 1H, J = 9.0, H-5), 7.80 (d, 1H, J = 2.2, H-8), 7.72 (d, 2H, J = 8.8, H-16),7.46 (dd, 1H, J = 2.2 e 9.0, H-6), 6.99 (d, 2H, J = 8.8, H-17), 6.61 (d, 1H, J = 5.4, H-3), 4.66 (t, 2H, J = 6.0, H-12), 3.85 (t, 2H, J = 5.6, H-11), 3.77 (s, 3H, H-19). 13C NMR (50 MHz, DMSO-d6): δ158.8 (C-17), 151.8 (C-1), 149.5 (C-3), 148.9 (C-8), 146.1 (C-13), 133.4 (C-6), 127.4 (C-12), 126.3 (C-15), 124.2 (C-7), 123.8 (C-4), 123.2 (C14), 120.8 (C-5), 117.3 (C-9), 114.1 (C-16), 98.7 (C-2), 55.0 (C-18), 47.7 (C-11), 42.2 (C-10).

7-chloro-N-(3-(4-(4-methoxyphenyl)-1H-1,2,3triazol-1-yl)propyl)quinolin-4-amine (25b)

Yellowish powder. m.p. 189.6-191.5 ºC, IR (λmax, cm1): 3319, 3111, 2929, 1612, 1581, 1498, 1453, 1224, 1177. 1H NMR (200 MHz, DMSO-d6): δ8.14 (d, 1H, J = 7.2, H-2), 8.00 (s, 1H, H-14), 7.97 (d, 1H, J = 9.0, H-5), 7.53 (d, 1H, J = 1.8, H-8), 7.35 - 7.29 (m, 3H, H-6 e H-17),6.73 (dd, 1H, J = 2.2 e 9.0, H-6), 6.99 (d, 2H, J = 8.8, H-17), 6.61 (d, 1H, J = 5.4, H-3), 4.66 (t, 2H, J = 6.0, H-12), 3.85 (t, 2H, J = 5.6, H-11), 3.77 (s, 3H, H-19). 13C NMR (50 MHz, DMSO-d6): δ158.8 (C-17), 151.8 (C-1), 149.5 (C-3), 148.9 (C-8), 146.1 (C-13), 133.4 (C-6), 127.4 (C-12), 126.3 (C-15), 124.2 (C-7), 123.8 (C-4), 123.2 (C-14), 120.8 (C5), 117.3 (C-9), 114.1 (C-16), 98.7 (C-2), 55.0 (C-18), 47.7 (C-11), 42.2 (C-10).

7-chloro-N-(2-(4-(4-fluorophenyl)-1H-1,2,3triazol-1-yl)ethyl)quinolin-4-amine (26a)

Yellowishpowder. m.p. 278.5-281.0 ºC, IR (λmax, cm-1): 3316, 3138, 2925, 1609, 1578, 1559, 1494, 1459. 1H NMR (200 MHz, MeOD): δ8.32 - 8.24 (m, 3H, H-2, H-5 e H-13), 7.85 (d, 1H, J = 1.8, H-8), 7.76 - 7.64 (m, 3H, H-6 e H-16), 7.17 - 7.08 (m, 2H, H-17), 6.77 (d, 1H, J = 7.2, H-3), 4.84 (t, 2H, J = 5.4, H-12), 4.18 (t, 2H, J = 5.4, H-11) 13C NMR (50 MHz, DMSO-d6): δ151.9 (C18), 151.8 (C-1), 149.6 (C3), 148.9 (C-8), 145.3 (C-13), 133.4 (C-6), 127.4 (C-15), 127.1 (C-12), 126.9 (C-14), 124.3 (C-7), 123.9 (C-4), 121.7 (C-5), 115.9 (C-9), 115.5 (C-16), 98.7 (C-2), 47.9 (C-11), 42.2 (C-10).

7-chloro-N-(3-(4-(4-fluorophenyl)-1H-1,2,3triazol-1-yl)propyl)quinolin-4-amine (26b)

Yellowish powder. m.p. 229.4-230.3 ºC, IR (λmax, cm-1): 3339, 3133, 2948, 1610, 1582, 1540, 1495, 1455. 1H NMR (200 MHz, MeOD): δ8.32 (d, 1H, J = 7.2, H-2), 8.26 (s, 1H, H-14), 8.18 (d, 1H, J = 9, H-5), 7.73 (d, 1H, J = 1.8, H-8), 7.66 - 7.59 (m, 2H, H-17), 7.51 (dd, 1H, J = 1.6 e 9.0, H-6), 7.14 - 7.05 (m, 2H, H-18), 6.82 (d, 1H, J = 7.2, H-3), 4.64 (t, 2H, J = 6.2, H-13), 3.73 (t, 2H, J = 6.6, H-11), 2.53 (q, 2H, J = 6.2 e 12.8, H-12). 13C NMR (50 MHz, MeOD): δ157.4 (C19), 148.0 (C-3), 143.8 (C-1), 140.9 (C-8), 139.9 (C-14), 128.5 (C-13), 128.3 (C-7), 127.8 (C-6), 125.8 (C-4), 122.4 (C-16), 120.2 (C-5), 119.7 (C-15), 117.0 (C-17), 116.9 (C-9), 99.7 (C-2), 49.5 (C-12), 42.5 (C10), 28.9 (C-11).

7-chloro-N-(2-(4-(4-(dimethylamino)phenyl)-1H-1,2,3-triazol-1-yl)ethyl)quinolin-4-amine (27a)

Yellowish powder. m.p. 220.0-222.7 ºC, IR(λmax, cm-1): 3277, 3142, 2886, 2806, 1619, 1580, 1458. 1H NMR (200 MHz, DMSO-d6): δ8.50 (s, 1H, H-13), 8.36 (d, 1H, J = 7.2, H-2), 8.28 (d, 1H, J = 9.2, H-5), 7.93 (d, 1H, J = 1.8, H-8), 7.87 (d, 2H, J = 8.6, H-16), 7.67 (dd, 1H, J = 2.0 e 9.2, H-6), 7.60 (d, 2H, J = 8.6, H-17), 6.83 (d, 1H, J = 7.2, H-3), 4.88 (t, 2H, J = 5.2, H-12), 4.20 (t, 2H, J = 5.4, H-11) and 3.27 (s, 6H, H-19). 13C NMR (50 MHz, DMSO-d6): δ151.9 (C-1), 149.9 (C-17), 149.6 (C-3), 149.0 (C-8), 146.8 (C-13), 133.4 (C-6), 127.5 (C7), 125.9 (C-5), 124.3 (C-4), 123.9 (C-12), 119.9 (C-15), 118.6 (C-14), 117.4 (C-9), 112.2 (C-16), 98.8 (C-2), 47.7 (C-11), 42.3 (C-10), 39.9 (C-18).

7-chloro-N-(3-(4-(4-(dimethylamino)phenyl)-1H-1,2,3-triazol-1-yl)propyl)quinolin-4-amine (27b)

Yellowish powder. m.p. 185.1-187.9 ºC, IR (λmax, cm-1): 3245, 3122, 3040, 2918, 2851, 1615, 1597, 1573, 1453. 1H NMR (200 MHz, MeOD): δ8.37 (s, 1H, H-14), 8.27 (d, 1H, J = 7.2, H-2), 8.11 (d, 1H, J = 9.2, H-5), 7.75 (d, 2H, J = 8.6, H-17), 7.66 (d, 1H, J = 2.0, H-8), 7.55 (d, 2H, J = 8.6, H-18), 7.40 (dd, 1H, J = 1.8 e 9.0, H-6), 6.77 (d, 1H, J = 7.2, H-3), 4.62 (t, 2H, J = 6.2, H-13), 3.69 (t, 2H, J = 6.2, H-11), 3.69 (s, 6H, H-20), 2.46 (q, 2H, J = 5.8 e 12.2, H-12). 13C NMR (50 MHz, MeOD): δ157.2 (C19), 147.1 (C-3), 144.4 (C-8), 143.7 (C-1), 140.6 (C-14), 139.7 (C-6), 128.5 (C-7), 128.1 (C-16), 125.9 (C-7), 123.3 (C-4), 123,2 (C-15), 121.3(C-5), 120.1 (C-17), 116.7 (C-9), 99.7 (C-2), 49.6 (C-12), 46.4 (C-19), 42.4 (C-10), 28.8 (C-11).

7-chloro-N-(2-(4-(6-methoxynaphthalen-2-yl)-1H-1,2,3-triazol-1-yl)ethyl)quinolin-4-amine (28a)

Yellowish powder. m.p. 244.3-246.3 ºC, IR (λmax, cm-1): 3341, 3063, 2936, 1610, 1580, 1452, 1220, 1162. 1H NMR (200 MHz, MeOD):δ8.41 (s, 1H, H-24), 8.29 (d, 1H, J = 1.6, H-8), 8.25 (d, 1H, J = 6.0, H-2), 8.08 (s, 1H, H-13), 7.81 (d, 1H, J = 3.2, H-21), 7.77-7.75 (m, 2H, H-2 e H-19), 7.20 (d, 1H, J = 3.2, H-22), 7.13 (dd, 1H, J = 2.4 e 8.9, H-6), 7.70-7.64 (m, 2H, H-16 e H-17), 6.74 (d, 1H, J = 7.2, H-3), 4.87 (t, 2H, J = 5.2, H-12), 4.19 (t, 2H, J = 5.8, H-11), 3.90 (s, 3H, OCH3). 13C NMR (50 MHz, DMSO-d6): δ157.4 (C-19), 151.8 (C-1), 149.6 (C-3), 149.0 (C-8), 146.4 (C-13), 133.8 (C-6), 133.5 (C-17), 129.4 (C16), 128.4 (C-14), 127.5 (C-12), 127.3 (C-21), 124.3 (C-7), 124.4 (C-5), 124.0 (C-15), 123.9 (C-4), 123.2 (C-5), 121.7 (C-23), 119.0 (C-20), 117.4 (C-9), 105.9 (C-18), 98.9 (C-2), 55.1 (OCH3), 47.9 (C-11), 42.3 (C-10).

7-chloro-N-(3-(4-(6-methoxynaphthalen-2-yl)-1H-1,2,3-triazol-1-yl)propyl)quinolin-4-amine (28b)

Yellowish powder. m.p. 197.8-199.0 ºC, IR (λmax, cm1): 3322, 3062, 2924, 1611, 1582, 1543, 1481, 1451, 1219, 1163. 1H NMR (200 MHz, DMSO-d6): δ8.67 (s, 1H, H-25), 8.39 (d, 1H, J = 5,4, H-2), 8.29 (sl, 1H, H-5), 8.25 (sl, 1H, H-23), 7.89 - 7.79 (m, 3H,H-8, H-17 e H-18), 7.47 - 7.33 (m, 3H, H-14, H-20 e H-22), 7.18 (dd, 1H, J = 1.4 e 8.8, H-6), 6.48 (d, 1H, J = 5,4, H-3), 4.87 (t, 2H, J = 6.4, H-13), 3.88 (s, 3H, OCH3), 3.38 (sl, H-11), 2.31 (q, 2H, J = 5.8 e 12.4, H-12). 13C NMR (50 MHz, DMSO-d6): δ157.3 (C-20), 151.8 (C-1), 149.9 (C-3), 148.9 (C-8), 146.5 (C-14), 133.8 (C-6), 133.3 (C-18), 129.4 (C-17), 128.4 (C-15), 127.4 (C-13), 127.2 (C-22), 125.9 (C-23), 124.0 (C-7/C-16), 123.3 (C-4/C-8), 121.3 (C-24), 19.0 (C-21), 117.4 (C-9), 105.9 (C-19), 98.7 (C-2), 55.1 (OCH3), 47.5 (C-12), 39.5 (C-10), 28.3 (C-11).

ACKNOWLEDGMENT

This work was supported by funds from the Brazilian institution - FAPEMIG (Fundação de Amparo à Pesquisa de Minas Gerais) (FIP 2014/9171-2S and FIP 2015/10113- 2S), as well as the CNPq (Conselho Nacional de

Desenvolvimento Científico e Tecnológico) and PROPPUFOP - Pró-Reitoria de Pesquisa e Pós-Graduação da UFOP, process number N.: 23109.003517/2018-85. The fellowship to Vitor Lourenço Campos and Thiago Martins Lages de Souza is also acknowledged.

REFERENCES

  • Andrade-Neto VF, Goulart MOF, Da Silva Filho JF, Da Silva MJ, Pinto MDCFR, Pinto AV, et al. Antimalarial activity of phenazines from lapachol, β-lapachone and its derivatives against Plasmodium falciparum in vitro and Plasmodium berghei in vivo. Bioorganic Med Chem Lett. 2004;14(5):11459.
  • Bakka TA, Strøm MB, Andersen JH, Gautun OR. Synthesis and antimicrobial evaluation of cationic low molecular weight amphipathic 1,2,3-triazoles. Bioorg Med Chem Lett. 2017;27(5):1119-23.
  • Barreiro EJ. Estratégia de simplificação molecular no planejamento racional de fármacos: a descoberta de novo agente cardioativo. Quim Nova. 2002;25(6b):1172-80.
  • Brown WH. Malarial Pigment (so-called Melanin): Its Nature and Mode of Production. J Exp Med. 1911;13(2):290-9.
  • Calvocalle JM, Moreno A, Eling WMC, Nardin EH. In Vitro Development of Infectious Liver Stages of P. yoelii and P. berghei Malaria in Human Cell Lines. Exp Parasitol. 1994;79(3):362-73.
  • Chopra R, Chibale K, Singh K. Pyrimidine-chloroquinoline hybrids: Synthesis and antiplasmodial activity. Eur J Med Chem. 2018;148:39-53.
  • Coronado LM, Nadovich CT, Spadafora C. Malarial hemozoin: From target to tool. Biochim Biophys Acta. 2014;1840(6):2032-41.
  • Guantai EM, Ncokazi K, Egan TJ, Gut J, Rosenthal PJ, Smith PJ, et al. Design, synthesis and in vitro antimalarial evaluation of triazole-linked chalcone and dienone hybrid compounds. Bioorg Med Chem. 2010,18(23):8243-56.
  • Guillon J, Mouray E, Moreau S, Mullié C, Forfar I, Desplat V, et al. New ferrocenic pyrrolo[1,2-a]quinoxaline derivatives: Synthesis, and in vitro antimalarial activity e Part II. Eur J Med Chem. 2011;46(6):2310-26.
  • Harvard Medical School. Malaria [Internet]. Boston. 2013.
  • Hou W, Luo Z, Zhang G, Cao D, Li D, Ruan H, et al. Click chemistry-based synthesis and anticancer activity evaluation of novel C-14 1,2,3-triazole dehydroabietic acid hybrids. Eur J Med Chem. 2017;138:1042-52.
  • Joshi MC, Wicht KJ, Taylor D, Hunter R, Smith PJ, Egan TJ. In vitro antimalarial activity, β-haematin inhibition and structure-activity relationships in a series of quinoline triazoles. Eur J Med Chem. 2013;69:338-47.
  • Kolb HC, Finn MG, Sharpless KB. Click Chemistry: Diverse Chemical Function from a Few Good Reactions. Angew Chem Int Ed Engl. 2001;40(11):2004-21.
  • Kouznetsov V V, Gó Mez-Barrio A. Recent developments in the design and synthesis of hybrid molecules based on aminoquinoline ring and their antiplasmodial evaluation. Eur J Med Chem. 2009;44:3091-113.
  • Kumar A, Srivastava K, Raja Kumar S, Puri SK, Chauhan PMS. Synthesis and bioevaluation of hybrid 4-aminoquinoline triazines as a new class of antimalarial agents. Bioorg Med Chem Lett. 2008;18(24):6530-3.
  • Kumar S, Saini A, Gut J, Rosenthal PJ, Raj R, Kumar V. 4-Aminoquinoline-chalcone/-N-acetylpyrazoline conjugates: Synthesis and antiplasmodial evaluation. Eur J Med Chem. 2017;138:993-1001.
  • Ladan H, Nitzan Y, Malik Z. The antibacterial activity of haemin compared with cobalt, zinc and magnesium protoporphyrin and its effect on potassium loss and ultrastructure of Staphylococcus aureus. FEMS Microbiol Lett. 1993;112(2):173-7.
  • Lambros C, Vanderberg JP. Synchronization of Plasmodium falciparum erythrocytic stages in culture. J Parasitol. 1979;65(3):418-20.
  • Madureira M, Paula Martins A, Gomes M, Paiva J, Proença Da Cunha A, Do Rosário V. Antimalarial activity of medicinal plants used in traditional medicine in S. Tomé and Príncipe islands. J Ethnopharmacol. 2002;81(1):23-9.
  • Manohar S, Khan SI, Rawat DS. Synthesis of 4-aminoquinoline-1,2,3-triazole and 4-aminoquinoline1,2,3-triazole-1,3,5-triazine hybrids as potential antimalarial agents. Chem Biol Drug Des. 2011;78(1):124-36.
  • Melato S, Prosperi D, Coghi P, Basilico N, Monti D. A Combinatorial Approach to 2,4,6-Trisubstituted Triazines with Potent Antimalarial Activity: Combining conventional synthesis and microwave-assistance. Chem Med Chem. 2008,3(6):873-6.
  • Mishra M, Mishra VK, Kashaw V, Iyer AK, Kashaw SK. Comprehensive review on various strategies for antimalarial drug discovery. Eur J Med Chem. 2016.
  • Mistry B, Patel R V., Keum Y-S. Access to the substituted benzyl-1,2,3-triazolyl hesperetin derivatives expressing antioxidant and anticancer effects. Arab J Chem. 2017;10(2):157-66.
  • Noedl H, Bronnert J, Yingyuen K, Attlmayr B, Kollaritsch H, Fukuda M. Simple histidine-rich protein 2 double-site sandwich enzyme-linked immunosorbent assay for use in malaria drug sensitivity testing. Antimicrob Agents Chemother. 2005;49(8):3575-7.
  • O’Neill PM, Bray PG, Hawley SR, Ward SA, Park BK. 4-Aminoquinolines-past, present, and future: a chemical perspective. Phmmmol Ther. 1998;77(1):29-58.
  • Okombo J, Chibale K. Insights into Integrated Lead Generation and Target Identification in Malaria and Tuberculosis Drug Discovery. Acc Chem Res. 2017;50(7):1606-16.
  • Pagola S, Stephens PW, Bohle DS, Kosar AD, Madsen SK. The structure of malaria pigment β-haematin. Nature. 2000;404(6775):307-10.
  • Pereira GR, Brandão GC, Arantes LM, De Oliveira HA, De Paula RC, Do Nascimento MFA, et al. 7-Chloroquinolinotriazoles: Synthesis by the azide-alkyne cycloaddition click chemistry, antimalarial activity, cytotoxicity and SAR studies. Eur J Med Chem. 2014;73:295-309.
  • Pérez BC, Teixeira C, Figueiras M, Gut J, Rosenthal PJ, Gomes JRB, et al. Novel cinnamic acid/4-aminoquinoline conjugates bearing non-proteinogenic amino acids: Towards the development of potential dual action antimalarials. Eur J Med Chem. 2012;54:887-99.
  • de Pilla Varotti F, Botelho ACC, Andrade AA, de Paula RC, Fagundes EMS, Valverde A, et al. Synthesis, Antimalarial Activity, and Intracellular Targets of MEFAS, a new hybrid compound derived from mefloquine and artesunate. Antimicrob Agents Chemother. 2008;52(11):3868-74.
  • Piper RC, Williams JA, Makler MT, Gibbins BL, Hinrichs DJ, Ries JM, et al. Parasite lactate dehydrogenase as an assay for Plasmodium falciparum drug sensitivity. Am J Trop Med Hyg. 1993;48(6):739-41.
  • Raj R, Singh P, Singh P, Gut J, Rosenthal PJ, Kumar V. Azide-alkyne cycloaddition en route to 1H-1,2,3-triazoletethered 7-chloroquinoline-isatin chimeras: Synthesis and antimalarial evaluation. Eur J Med Chem. 2013;62:590-6.
  • Rostovtsev VV, Green LG, Fokin VV, Sharpless KB. A stepwise huisgen cycloaddition process: copper(I)-catalyzed regioselective “ligation” of azides and terminal alkynes. Angew Chemie Int Ed Engl. 2002;41(14):2596-9.
  • De Sá MS, Costa JFO, Krettli AU, Zalis MG, De Azevedo Maia GL, Sette IMF, et al. Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice. Parasitol Res. 2009;105(1):275-9.
  • Sherman IW, Tanigoshi L. Incorporation of 14C-amino-acids by malaria (Plasmodium lophurae) IV. In vivo utilization of host cell haemoglobin. Int J Biochem. 1970,1(5):635-7.
  • da Silva EN, de Melo IMM, Diogo EBT, Costa VA, de Souza Filho JD, Valença WO, et al. On the search for potential anti-Trypanosoma cruzi drugs: Synthesis and biological evaluation of 2-hydroxy-3-methylamino and 1,2,3-triazolic naphthoquinoidal compounds obtained by click chemistry reactions. Eur J Med Chem. 2012;52:304-12.
  • Sullivan DJ, Gluzman IY, Russell DG, Goldberg DE. On the molecular mechanism of chloroquine’s antimalarial action. Proc Natl Acad Sci USA. 1996;93(21):11865-70.
  • Sunduru N, Sharma M, Srivastava K, Rajakumar S, Puri SK, Saxena JK, et al. Synthesis of oxalamide and triazine derivatives as a novel class of hybrid 4-aminoquinoline with potent antiplasmodial activity. Bioorg Med Chem. 2009;17(17):6451-62.
  • Trager W, Jensen JB. Human malaria parasites in continuous culture. Science. 1976;193(4254):673-5.
  • Twentyman P, Luscombe M. A study of some variables in a tetrazolium dye (MTT) based assay for cell growth and chemosensitivity. Br J Cancer. 1987;56(3):279-85.
  • WHO. World Malaria Report 2018 [Internet]. WHO. Geneva: World Health Organization. 2018.
  • Yamada R, Hiraizumi M, Narita S, Sakurai K. Two-step synthesis of a clickable photoaffinity probe from an anticancer saponin OSW-1 and its photochemical reactivity. Asian J Org Chem. 2016;5(3):330-4.
  • Ziegler J, Linck R, Wright D. Heme Aggregation Inhibitors: Antimalarial Drugs Targeting an Essential Biomineralization Process. Curr Med Chem. 2001;8(2):171-89.

Publication Dates

  • Publication in this collection
    26 Nov 2021
  • Date of issue
    2021

History

  • Received
    21 Dec 2018
  • Accepted
    29 Sept 2019
Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Av. Prof. Lineu Prestes, n. 580, 05508-000 S. Paulo/SP Brasil, Tel.: (55 11) 3091-3824 - São Paulo - SP - Brazil
E-mail: bjps@usp.br