Synthesis and characterisation of new antimalarial fluorinated triazolopyrazine compounds

• Kah Yean Lum,
• Jonathan M. White,
• Daniel J. G. Johnson,
• Vicky M. Avery and
• Rohan A. Davis

Beilstein J. Org. Chem. 2023, 19, 107–114, doi:10.3762/bjoc.19.11

• -ray crystallographic studies and confirmed the NMR-based structure assignment. Key COSY, HMBC, and ROESY correlations, and ORTEP drawing of compound 18 are shown in Figure 1. All compounds were tested for their antimalarial activity against P. falciparum 3D7 (chloroquine-sensitive strain) and Dd2

• (chloroquine, pyrimethamine and mefloquine drug-resistant strain) (Table 1). In terms of the cLogP values of these compounds, an increase in hydrophobicity did not improve the potency. A similar trend was also observed in a previous study [20], where an increase in the hydrophobicity of several

Synthetic study toward the diterpenoid aberrarone

• Liang Shi,
• Zhiyu Gao,
• Yiqing Li,
• Yuanhao Dai,
• Yu Liu,
• Lili Shi and
• Hong-Dong Hao

Beilstein J. Org. Chem. 2022, 18, 1625–1628, doi:10.3762/bjoc.18.173

• antitumor, antituberculosis and antimalarial activities [2][3][4][5][6]. Among these structurally intriguing natural products, aberrarone (1) shows antimalarial activity against the chloroquine-resistant strain of Plasmodium falciparum (IC50 = 10 μg/mL) [7]. Structurally, aberrarone possesses an unusual

Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities

• Viktor A. Zapol’skii,
• Isabell Berneburg,
• Ursula Bilitewski,
• Melissa Dillenberger,
• Katja Becker,
• Stefan Jungwirth,
• Aditya Shekhar,
• Bastian Krueger and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54

• -(1H-1,2,4-triazol-1-yl)-1H-pyrazol-1-yl)quinoline (3b) and 7-chloro-4-(3-((4-chlorophenyl)thio)-5-(dichloromethyl)-4-nitro-1H-pyrazol-1-yl)quinoline (9e) inhibited the growth of the chloroquine-sensitive Plasmodium falciparum strain 3D7 with EC50 values of 0.2 ± 0.1 µM (85 ng/mL, 200 nM) and 0.2

• ± 0.04 µM (100 ng/mL, 200 nM), respectively. Two compounds (3b and 10d) have also been tested for anti-SARS-CoV-2, antibacterial, and cytotoxic activity. Keywords: antimalarial activity; anti-SARS-CoV-2 activity; chloroquine; 2-nitroperchlorobutadiene; nucleophilic vinylic substitution; 1H-pyrazoles

• ; Introduction Tropical malaria remains one of the most devastating human diseases with over half of the world’s population being at risk of infection. In 2019, there were 229 million cases of malaria worldwide resulting in an estimated 409,000 fatalities [1]. Chloroquine has been utilized extensively for

First total synthesis of hoshinoamide A

• Haipin Zhou,
• Zihan Rui,
• Yiming Yang,
• Shengtao Xu,
• Yutian Shao and
• Long Liu

Beilstein J. Org. Chem. 2021, 17, 2924–2931, doi:10.3762/bjoc.17.201

• 210009, China Taizhou Medical Hi-Tech Development Public Services Platform, Taizhou 225300, China 10.3762/bjoc.17.201 Abstract Hoshinoamides A, B and C, linear lipopeptides, were isolated from the marine cyanobacterium Caldora penicillata, with potent antiplasmodial activity against chloroquine

• , hoshinoamides A, B [11] and C [12], from a microbial metabolite of marine cyanobacterium Caldora penicillata (Figure 1). Hoshinoamides A and B showed potent activities against chloroquine-sensitive Plasmodium falciparum 3D7 with IC50 values of 0.52 and 1.0 μM, respectively. Hoshinoamide C inhibited the growth

Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications

• Nikita Brodyagin,
• Martins Katkevics,
• Venubabu Kotikam,
• Christopher A. Ryan and
• Eriks Rozners

Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116

• ]. However, the uptake of most PNA–CPP conjugates is limited by endosomal entrapment. While the uptake can be improved either by increasing the concentration of PNA–CPP conjugates or by using endosomolytic compounds (for example, chloroquine or calcium ions) this leads to toxicity that is not viable for in

One-pot activation–alkynylation–cyclization synthesis of 1,5-diacyl-5-hydroxypyrazolines in a consecutive three-component fashion

• Christina Görgen,
• Katharina Boden,
• Guido J. Reiss,
• Walter Frank and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2019, 15, 1360–1370, doi:10.3762/bjoc.15.136

• shown nanomolar in vitro activities against chloroquine-sensitive and resistant strains of Plasmodium falciparum and can therefore be considered for the treatment of malaria [21]. Furthermore, similar derivatives have shown micromolar and submicromolar activity against 60 selected cancer cell lines

Doebner-type pyrazolopyridine carboxylic acids in an Ugi four-component reaction

• Maryna V. Murlykina,
• Oleksandr V. Kolomiets,
• Maryna M. Kornet,
• Yana I. Sakhno,
• Sergey M. Desenko,
• Victoriya V. Dyakonenko,
• Svetlana V. Shishkina,
• Oleksandr A. Brazhko,
• Vladimir I. Musatov,
• Alexander V. Tsygankov,
• Erik V. Van der Eycken and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2019, 15, 1281–1288, doi:10.3762/bjoc.15.126

• discovery. The target products containing a heterocyclic core bound to a peptide-like chain also showed a broad spectrum of biological activity: β-secretase (BACE1) inhibitory activity [15]; inducing apoptosis in colorectal cancer cells [16]; antimalarial activity against a chloroquine (CQ) non-resistant

Study on the regioselectivity of the N-ethylation reaction of N-benzyl-4-oxo-1,4-dihydroquinoline-3-carboxamide

• Pedro N. Batalha,
• Luana da S. M. Forezi,
• Maria Clara R. Freitas,
• Nathalia M. de C. Tolentino,
• Ednilsom Orestes,
• José Walkimar de M. Carneiro,
• Fernanda da C. S. Boechat and
• Maria Cecília B. V. de Souza

Beilstein J. Org. Chem. 2019, 15, 388–400, doi:10.3762/bjoc.15.35

• ; regioselectivity; Introduction Since the discovery of the antibacterial agent nalidixic acid, as a byproduct from the synthesis of chloroquine, the medicinal interest in 4-oxoquinolines as bioactive substances has exponentially grown over the years. Nowadays, some of the most important antibiotics used in the

Synthesis and biological evaluation of 1,2-disubstituted 4-quinolone analogues of Pseudonocardia sp. natural products

• Stephen M. Geddis,
• Teodora Coroama,
• Suzanne Forrest,
• James T. Hodgkinson,
• Martin Welch and
• David R. Spring

Beilstein J. Org. Chem. 2018, 14, 2680–2688, doi:10.3762/bjoc.14.245

• -product generated during the synthesis of the antimalarial chloroquine [2]. Given this high potential for the discovery of useful chemical entities, we have recently been engaged in research regarding a family of quinolone natural products which are produced by the actinomycete Pseudonocardia sp. CL38489

An overview of recent advances in duplex DNA recognition by small molecules

• Sayantan Bhaduri,
• Nihar Ranjan and
• Dev P. Arya

Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93

• activity against a chloroquine sensitive (3D7) and resistant (Dd2) strain of Plasmodium falciparum [100]. Conjugates with an alkene link between the two N-terminal building blocks and a C-alkylthiazole moiety appeared to the most active among others with IC50 values in the range of 30–500 nM. The same

High-yielding continuous-flow synthesis of antimalarial drug hydroxychloroquine

• Eric Yu,
• Hari P. R. Mangunuru,
• Nakul S. Telang,
• Caleb J. Kong,
• Jenson Verghese,
• Stanley E. Gilliland III,
• Saeed Ahmad,
• Raymond N. Dominey and
• B. Frank Gupton

Beilstein J. Org. Chem. 2018, 14, 583–592, doi:10.3762/bjoc.14.45

• of the malaria parasite Plasmodium falciparum. Hydroxychloroquine (1) is an antimalarial drug developed for both treatment and prevention of the disease in response to the widespread malaria resistance to chloroquine (2, Figure 1) [5][6]. Additionally, hydroxychloroquine (1, HCQ) is an effective non

Pyridinoacridine alkaloids of marine origin: NMR and MS spectral data, synthesis, biosynthesis and biological activity

• Louis P. Sandjo,
• Victor Kuete and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2015, 11, 1667–1699, doi:10.3762/bjoc.11.183

• subtilis, giving a MIC of 3.1 µg/mL [87]. 42 displayed in vitro antiparasitic activity against Plasmodium falciparum (K1, NF54), Leshmania donovani, Trypanosoma cruzi and T. rhodesiense but the effect was much lower than that of standard drugs artemisinin and chloroquine [88]. Ascididemin (42) displayed

(2R,1'S,2'R)- and (2S,1'S,2'R)-3-[2-Mono(di,tri)fluoromethylcyclopropyl]alanines and their incorporation into hormaomycin analogues

• Armin de Meijere,
• Sergei I. Kozhushkov,
• Dmitrii S. Yufit,
• Christian Grosse,
• Marcel Kaiser and
• Vitaly A. Raev

Beilstein J. Org. Chem. 2014, 10, 2844–2857, doi:10.3762/bjoc.10.302

• used: L. donovani, MHOM/ET/67/L82, axenic amastigote forms, miltefosine, IC50 of 0.143 μg/mL; P. falciparum, K1 (chloroquine and pyrimethamine resistant), erythrocytic stages, chloroquine, IC50 of 0.089 μg/mL and L6 cells, rat skeletal myoblasts, podophyllotoxin, IC50 of 0.006 μg/mL. Structure and

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

• Alexander O. Terent'ev,
• Dmitry A. Borisov,
• Vera A. Vil’ and
• Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

• million cases of malaria occur each year, and 2 million people die from it [47][48]. Due to a high degree of resistance in malaria to traditional drugs as quinine, chloroquine, and mefloquine, an active search for other classes of new drugs is performed. In this respect, organic peroxides play a

• intermediate ozonide 196 that on treatment with 2-methylpropane-1,2-diamine finally gives the target compound (Scheme 53). The in vitro and in vivo studies showed that arterolane is more active against causative agents of malaria than artemisinin, chloroquine, and mefloquine [77][78][81]. 3. Synthesis of 1,2

Synthesis and biological activities of the respiratory chain inhibitor aurachin D and new ring versus chain analogues

• Xu-Wen Li,
• Jennifer Herrmann,
• Yi Zang,
• Philippe Grellier,
• Soizic Prado,
• Rolf Müller and
• Bastien Nay

Beilstein J. Org. Chem. 2013, 9, 1551–1558, doi:10.3762/bjoc.9.176

• (e.g., via enhanced ROS formation) [29]. However, at the highest assay concentration also shorter chain analogues 9–11 reduced the MMP to approximately 60–80% of the control value as exemplarily shown for geranyl analogue 9 (Figure 2B). Antiparasitic activities were evaluated on the chloroquine

Synthesis of 2-amino-3-arylpropan-1-ols and 1-(2,3-diaminopropyl)-1,2,3-triazoles and evaluation of their antimalarial activity

• Matthias D’hooghe,
• Stéphanie Vandekerckhove,
• Karen Mollet,
• Karel Vervisch,
• Stijn Dekeukeleire,
• Liesbeth Lehoucq,
• Carmen Lategan,
• Peter J. Smith,
• Kelly Chibale and
• Norbert De Kimpe

Beilstein J. Org. Chem. 2011, 7, 1745–1752, doi:10.3762/bjoc.7.205

• antiplasmodial activity against both a chloroquine-sensitive and a chloroquine-resistant strain of Plasmodium falciparum with IC50-values of ≤25 μM. Keywords: aminopropanes; antimalarial activity; aziridines; β-lactams; ring opening; Introduction Malaria remains a major issue in health control, especially in

• parasite Plasmodium falciparum, too. Biological evaluation At first, compounds 6a–c, 8a–e, 9a–d, 12a,b, 14a–e, 15a–f and 16a–g were screened for in vitro antiplasmodial activity. All samples were tested in triplicate on one occasion against a chloroquine-sensitive (CQS) strain of P. falciparum (D10). Those

• samples showing antiplasmodial activity were then tested in triplicate on one occasion against a chloroquine-resistant (CQR) strain of P. falciparum (Dd2) and screened for in vitro cytotoxicity against a Chinese hamster ovary (CHO) cell-line, in triplicate on one occasion. The antiplasmodial and