scholarly journals Potent Antiplasmodial Derivatives of the Antitussive Drug Dextromethorphan Reveal the Ent-Morphinan Pharmacophore of Tazopsine-Type Alkaloids

Author(s):  
Antoinette Keita ◽  
Jean-François Franetich ◽  
Maelle Carraz ◽  
Loise Valentin ◽  
Mallaury Bordesoulles ◽  
...  

The alkaloid tazopsine 1 was introduced in the late 2000's as a novel antiplasmodial hit compound active against Plasmodium falciparum hepatic stages, with potential to develop prophylactic drugs based on this novel chemical scaffold. However, the structural determinants of tazopsine 1 bioactivity, together with the exact definition of the pharmacophore, remained elusive, impeding further development. We found that the antitussive drug dextromethorphan (DXM) 3, although lacking the complex pattern of stereospecific functionalization of the natural hit, was harboring significant antiplasmodial activity in vitro despite suboptimal prophylactic activity in a murine model of malaria, which precluded its direct repurposing against malaria. The targeted N-alkylation of nor-DXM 15 delivered a small library of analogues with greatly improved activity over DXM 3 against P. falciparum asexual stages. Amongst these, N-2’-pyrrolylmethyl-nor-DXM 16i showed a 2- to 36-fold superior inhibitory potency compared to tazopsine 1 and DXM 3 against parasite liver and blood stages, with 760 ± 130 nM and 2.1 ± 0.4 µM IC50 values, respectively, as well as liver/blood phase selectivity of 2.8. Furthermore, cpd. 16i showed a 5 to 8-fold increase of activity relatively to DXM 3 against P. falciparum stages I-II and V gametocytes, with 18.5 µM and 13.2 µM IC50 values, respectively. Cpd. 16i can thus be considered a promising novel hit compound against malaria in the ent-morphinan series with putative pan-cycle activity, paving the way for further therapeutic development (e. g., investigation of its prophylactic activity in a mouse model of malaria).

2020 ◽  
Vol 16 ◽  
Author(s):  
Lucas da Silva Santos ◽  
Matheus Fillipe Langanke de Carvalho ◽  
Ana Claudia de Souza Pinto ◽  
Amanda Luisa da Fonseca ◽  
Julio César Dias Lopes ◽  
...  

Background: Malaria greatly affects the world health, having caused more than 228 million cases only in 2018. The emergence of drug resistance is one of the main problems in its treatment, demonstrating the urge for the development of new antimalarial drugs. Objective: Synthesis and in vitro antiplasmodial evaluation of triazole compounds derived from isocoumarins and a 3,4- dihydroisocoumarin. Method: The compounds were synthesized in 4 to 6-step reactions with the formation of the triazole ring via the Copper(I)-catalyzed 1,3-dipolar cycloaddition between isocoumarin or 3,4-dihydroisocoumarin azides and terminal alkynes. This key reaction provided compounds with an unprecedented connection of isocoumarin or 3,4-dihydroisocoumarin and the 1,2,3-triazole ring. The products were tested for their antiplasmodial activity against a Plasmodium falciparum chloroquine resistant and sensitive strains (W2 and 3D7, respectively). Results: Thirty-one substances were efficiently obtained by the proposed routes with an overall yield of 25-53%. The active substances in the antiplasmodial test displayed IC50 values ranging from 0.68-2.89 μM and 0.85-2.07 μM against W2 and 3D7 strains, respectively.


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 739
Author(s):  
Sameh S. Elhady ◽  
Reda F. A. Abdelhameed ◽  
Mayada M. El-Ayouty ◽  
Amany K. Ibrahim ◽  
Eman S. Habib ◽  
...  

In this study isolates from Thymelaea hirsuta, a wild plant from the Sinai Peninsula of Egypt, were identified and their selective cytotoxicity levels were evaluated. Phytochemical examination of the ethyl acetate (EtOAc) fraction of the methanolic (MeOH) extract of the plant led to the isolation of a new triflavanone compound (1), in addition to the isolation of nine previously reported compounds. These included five dicoumarinyl ethers found in Thymelaea: daphnoretin methyl ether (2), rutamontine (3), neodaphnoretin (4), acetyldaphnoretin (5), and edgeworthin (6); two flavonoids: genkwanin (7) and trans-tiliroside (8); p-hydroxy benzoic acid (9) and β sitosterol glucoside (10). Eight of the isolated compounds were tested for in vitro cytotoxicity against Vero and HepG2 cell lines using a sulforhodamine-B (SRB) assay. Compounds 1, 2 and 5 exhibited remarkable cytotoxic activities against HepG2 cells, with IC50 values of 8.6, 12.3 and 9.4 μM, respectively, yet these compounds exhibited non-toxic activities against the Vero cells. Additionally, compound 1 further exhibited promising cytotoxic activity against both MCF-7 and HCT-116 cells, with IC50 values of 4.26 and 9.6 μM, respectively. Compound 1 significantly stimulated apoptotic breast cancer cell death, resulting in a 14.97-fold increase and arresting 40.57% of the cell population at the Pre-G1 stage of the cell cycle. Finally, its apoptosis-inducing activity was further validated through activation of BAX and caspase-9, and inhibition of BCL2 levels. In silico molecular docking experiments revealed a good binding mode profile of the isolates towards Ras activation/pathway mitogen-activated protein kinase (Ras/MAPK); a common molecular pathway in the development and progression of liver tumors.


Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1078 ◽  
Author(s):  
Silvia Bittner Fialová ◽  
Martin Kello ◽  
Matúš Čoma ◽  
Lívia Slobodníková ◽  
Eva Drobná ◽  
...  

On its own, rosmarinic acid possesses multiple biological activities such as anti-inflammatory, antimicrobial, cardioprotective and antitumor properties, and these are the consequence of its ROS scavenging and inhibitory effect on inflammation. In this study, two quaternary phosphonium salts of rosmarinic acid were prepared for the purpose of increasing its penetration into biological systems with the aim of improving its antimicrobial, antifungal, antiprotozoal and antitumor activity. The synthetized molecules, the triphenylphosphonium and tricyclohexylphosphonium salts of rosmarinic acid, exhibited significantly stronger inhibitory effects on the growth of HCT116 cells with IC50 values of 7.28 or 8.13 μM in comparison to the initial substance, rosmarinic acid (>300 μM). For the synthesized derivatives, we detected a greater than three-fold increase of activity against Acanthamoeba quina, and a greater than eight-fold increase of activity against A. lugdunensis in comparison to rosmarinic acid. Furthermore, we recorded significantly higher antimicrobial activity of the synthetized derivatives when compared to rosmarinic acid itself. Both synthetized quaternary phosphonium salts of rosmarinic acid appear to be promising antitumor and antimicrobial agents, as well as impressive molecules for further research.


Molecules ◽  
2019 ◽  
Vol 24 (7) ◽  
pp. 1307 ◽  
Author(s):  
Eliška Kohelová ◽  
Rozálie Peřinová ◽  
Negar Maafi ◽  
Jan Korábečný ◽  
Daniela Hulcová ◽  
...  

Twelve derivatives 1a–1m of the β-crinane-type alkaloid haemanthamine were developed. All the semisynthetic derivatives were studied for their inhibitory potential against both acetylcholinesterase and butyrylcholinesterase. In addition, glycogen synthase kinase 3β (GSK-3β) inhibition potency was evaluated in the active derivatives. In order to reveal the availability of the drugs to the CNS, we elucidated the potential of selected derivatives to penetrate through the blood-brain barrier (BBB). Two compounds, namely 11-O-(2-methylbenzoyl)-haemanthamine (1j) and 11-O-(4-nitrobenzoyl)-haemanthamine (1m), revealed the most intriguing profile, both being acetylcholinesterase (hAChE) inhibitors on a micromolar scale, with GSK-3β inhibition properties, and predicted permeation through the BBB. In vitro data were further corroborated by detailed inspection of the compounds’ plausible binding modes in the active sites of hAChE and hBuChE, which led us to provide the structural determinants responsible for the activity towards these enzymes.


Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3142 ◽  
Author(s):  
Bao Vue ◽  
Sheng Zhang ◽  
Andre Vignau ◽  
Guanglin Chen ◽  
Xiaojie Zhang ◽  
...  

As part of our ongoing silybin project, this study aims to introduce a basic nitrogen-containing group to 7-OH of 3,5,20-O-trimethyl-2,3-dehydrosilybin or 3-OH of 5,7,20-O-trimethyl-2,3-dehydrosilybin via an appropriate linker for in vitro evaluation as potential anti-prostate cancer agents. The synthetic approaches to 7-O-substituted-3,5,20-O-trimethyl-2,3-dehydrosilybins through a five-step procedure and to 3-O-substituted-5,7,20-O-trimethyl-2,3- dehydrosilybins via a four-step transformation have been developed. Thirty-two nitrogen-containing derivatives of silybin have been achieved through these synthetic methods for the evaluation of their antiproliferative activities towards both androgen-sensitive (LNCaP) and androgen-insensitive prostate cancer cell lines (PC-3 and DU145) using the WST-1 cell proliferation assay. These derivatives exhibited greater in vitro antiproliferative potency than silibinin. Among them, 11, 29, 31, 37, and 40 were identified as five optimal derivatives with IC50 values in the range of 1.40–3.06 µM, representing a 17- to 52-fold improvement in potency compared to silibinin. All these five optimal derivatives can arrest the PC-3 cell cycle in the G0/G1 phase and promote PC-3 cell apoptosis. Derivatives 11, 37, and 40 are more effective than 29 and 31 in activating PC-3 cell apoptosis.


2020 ◽  
Vol 21 (15) ◽  
pp. 5334 ◽  
Author(s):  
Ana Teresa Silva ◽  
Lis Lobo ◽  
Isabel S. Oliveira ◽  
Joana Gomes ◽  
Cátia Teixeira ◽  
...  

Ionic liquids derived from classical antimalarials are emerging as a new approach towards the cost-effective rescuing of those drugs. Herein, we disclose novel surface-active ionic liquids derived from chloroquine and natural fatty acids whose antimalarial activity in vitro was found to be superior to that of the parent drug. The most potent ionic liquid was the laurate salt of chloroquine, which presented IC50 values of 4 and 110 nM against a chloroquine-sensitive and a chloroquine-resistant strain of Plasmodium falciparum, respectively, corresponding to an 11- and 6-fold increase in potency as compared to the reference chloroquine bisphosphate salt against the same strains. This unprecedented report opens new perspectives in both the fields of malaria chemotherapy and of surface-active ionic liquids derived from active pharmaceutical ingredients.


2012 ◽  
Vol 77 (5) ◽  
pp. 589-597 ◽  
Author(s):  
Manav Malhotra ◽  
Manu Arora ◽  
Abdul Samad ◽  
Kapendra Sahu ◽  
Priyanka Phogat ◽  
...  

A novel series of Mannich which contained isoniaside were prepared. First by the reaction of 2-propoxybenzaldehyde with isoniazid corresponding hydrazone (2a) was obtained. After that, product 2a after mannich reaction of aminomethylation with formaldehyde and secondary give amines (2b-2k). The inhibitory potencies of the synthesized compounds were assayed in vitro against a panel of microorganisms and against A549 human lung adenocarcinoma cell line. Compounds 2c and 2k displayed moderate to potent antimicrobial activity against all the tested strains and they also exhibited significant cytotoxicity in a dose-dependent manner with an IC50 values ranging from 2.84 to 8.55 (?g) and 0.007-0.030 (?M). The structures of newly synthesized compounds were evaluated by elemental and spectral (IR, 1HNMR, 13C-NMR) methods. The result demonstrates the potential and importance of developing new mannich bases which would be effective against resistant microbial strain and they may be useful leads for anticancer drug development in the future.


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6980
Author(s):  
Pranab K. Bhadra ◽  
Rachael N. Magwaza ◽  
Niroshini Nirmalan ◽  
Sally Freeman ◽  
Jill Barber ◽  
...  

Erythromycin A is an established anti-bacterial agent against Gram-positive bacteria, but it is unstable to acid. This led to an evaluation of erythromycin B and its derivatives because these have improved acid stability. These compounds were investigated for their anti-malarial activities, by their in silico molecular docking into segments of the exit tunnel of the apicoplast ribosome from Plasmodium falciparum. This is believed to be the target of the erythromycin A derivative, azithromycin, which has mild anti-malarial activity. The erythromycin B derivatives were evaluated on the multi-drug (chloroquine, pyrimethamine, and sulfadoxine)-resistant strain K1 of P. falciparum for asexual growth inhibition on asynchronous culture. The erythromycin B derivatives were identified as active in vitro inhibitors of asexual growth of P. falciparum with low micro-molar IC50 values after a 72 h cycle. 5-Desosaminyl erythronolide B ethyl succinate showed low IC50 of 68.6 µM, d-erythromycin B 86.8 µM, and erythromycin B 9-oxime 146.0 µM on the multi-drug-resistant K1 of P. falciparum. Based on the molecular docking, it seems that a small number of favourable interactions or the presence of unfavourable interactions of investigated derivatives of erythromycin B with in silico constructed segment from the exit tunnel from the apicoplast of P. falciparum is the reason for their weak in vitro anti-malarial activities.


2018 ◽  
Vol 10 (4) ◽  
pp. 18
Author(s):  
Rajanna Ajumeera ◽  
Ganapathi Thipparapu ◽  
Shireesha Boyapati ◽  
Bharath Singh Padya ◽  
Vijayalaxmi Venkatesan

Novel N – triazolyl 3(a-f) and O-triazolyl (4a-f) derivatives of 4, 6-diaryl-1, 4-dihydropyrimidines were synthesized through mannich reaction. All compounds were characterized by physical and spectral data. These compounds were screened for in vitro efficiency in human breast cancer cell (MCF-7&MDA-MB-231) lines and found to have very good anti-proliferative activity.  Among all compounds of 4b, 3e, 4e endowed with lesser respective IC50 values of 31.94, 55.73, 55.03 µM in MCF-7 cells and 41.50, 35.28, 32.06 µM in MDA-MB 231 cells by MTT assay. In further studies, Compounds 4b, 3e, 4e were found to arrest cell growth at S phase in MCF-7 cells. In MDA-MB 231 cells, 4b, 4e were found to arrest the cells in S phase, and compound 3e found to arrest G2/M phase when compared to the standard drug tamoxifen, arrested S phase in MCF-7 cells and G0/G1 phase in MDA-MB 231 cells.


2020 ◽  
Vol 13 (12) ◽  
pp. 460
Author(s):  
Gabriela Brzuska ◽  
Gabriela Pastuch-Gawolek ◽  
Monika Krawczyk ◽  
Boguslaw Szewczyk ◽  
Ewelina Krol

Tick-borne encephalitis virus (TBEV) transmitted by ticks is a pathogen of great medical importance. As still no effective antiviral treatment is available, in the present study, a series of uridine glycoconjugates containing amide or/and 1,2,3-triazole moiety in the linker structure was synthesized and evaluated for the antiviral activity against two strains of TBEV: a highly virulent Hypr strain and less virulent Neudoerfl strain, using standardized previously in vitro assays. Our data have shown that four compounds from the series (18–21) possess strong activity against both TBEV strains. The half maximal inhibitory concentration (IC50) values of compounds 18–21 were between 15.1 and 3.7 μM depending on the virus strain, which along with low cytotoxicity resulted in high values of the selectivity index (SI). The obtained results suggest that these compounds may be promising candidates for further development of new therapies against flaviviruses.


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