An extensive phytochemical investigation of the EtOH/H2O (7:3) extracts of Sida rhombifolia L. and Sida acuta Burm. f., yielded a previously undescribed ceramide named rhombifoliamide (1) and a xylitol dimer (2), naturally isolated here for the first time, as well as the thirteen known compounds viz, oleanolic acid (3), β-amyrin glucoside (4), ursolic acid (5), β-sitosterol glucoside (6), tiliroside (7), 1,6-dihydroxyxanthone (8), a mixture of stigmasterol (9) and β-sitosterol (10), cryptolepine (11), 20-Hydroxyecdysone (12), (E)-suberenol (13), thamnosmonin (14) and xanthyletin (15).
Antimalarial drugs with novel modes of action and wide therapeutic potential are needed to pave the way for malaria eradication. Violacein is a natural compound known for its biological activity against cancer cells and several pathogens, including the malaria parasite, Plasmodium falciparum (Pf). Herein, using chemical genomic profiling (CGP), we found that violacein affects protein homeostasis. Mechanistically, violacein binds Pf chaperones, PfHsp90 and PfHsp70-1, compromising the latter's ATPase and chaperone activities.
Chloroquine (CQ) has been the main treatment for malaria in regions where there are no resistant strains. Molecular hybridization techniques have been used as a tool in the search for new drugs and was implemented in the present study in an attempt to produce compound candidates to treat malarial infections by CQ-resistant strains. Two groups of molecules were produced from the 4-aminoquinoline ring in conjugation to hydrazones (HQ) and imines (IQ).
In previous studies, Cassia spectabilis DC leaf has shown a good antiplasmodial activity. Therefore, this study is a follow-up study of the extract of leaf of C. spectabilis DC on its in vitro and in vivo antiplasmodial activity and mechanism as an antimalarial.
Malaria elimination can benefit from time and cost-efficient approaches for antimalarials such as drug repurposing. In this work, 796 DrugBank compounds were screened against 36 Plasmodium falciparum targets using QuickVina-W. Hits were selected after rescoring using GRaph Interaction Matching (GRIM) and ligand efficiency metrics: surface efficiency index (SEI), binding efficiency index (BEI) and lipophilic efficiency (LipE).
Malaria is an enormous threat to public health, due to the emergence of Plasmodium falciparum resistance to widely-used antimalarials, such as chloroquine (CQ). Current antimalarial drugs are aromatic heterocyclic derivatives, most often containing a basic component with an added alkyl chain in their chemical structure. While these drugs are effective, they have many side effects. This paper presents the synthesis and preliminary physicochemical characterisation of novel bioinspired imidazolidinedione derivatives, where the imidazolidinedione core was linked via the alkylene chain and the basic piperazine component to the bicyclic system.
Harmicines represent hybrid compounds composed of β-carboline alkaloid harmine and cinnamic acid derivatives (CADs). In this paper we report the synthesis of amide-type harmicines and the evaluation of their biological activity. N-harmicines 5a-f and O-harmicines 6a-h were prepared by a straightforward synthetic procedure, from harmine-based amines and CADs using standard coupling conditions, 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo [4,5-b]pyridinium 3-oxid hexafluorophosphate (HATU) and N,N-diisopropylethylamine (DIEA).
Cissampelos pareira is used traditionally in India as a remedy for the treatment of various diseases including malaria but the active ingredients responsible for antiplasmodial activity have not yet been investigated.
The Nigerian and South African varieties of Siphonochilus aethiopicus were examined for their phytochemical constituents. The ethyl acetate extract of the rhizomes of the South African variety yielded a novel diarylheptanoid, 2,3-diacetoxy-7-(3'',4''-dihydroxy-5''-methoxyphenyl)-1-(4'-hydroxy-3'-methoxyphenyl)-5-heptene and the flavonoid 3,7-dimethoxyquercetin. From the hexane extract of the Nigerian variety, siphonochilone and another flavonoid, 3,4',7-trimethylkaempferol were isolated.
The search for antimalarial chemotypes with modes of action unrelated to existing drugs has intensified with the recent failure of first-line therapies across Southeast Asia. Here, we show that the trisubstituted imidazole MMV030084 potently inhibits hepatocyte invasion by Plasmodium sporozoites, merozoite egress from asexual blood stage schizonts, and male gamete exflagellation.