Investigations of amination reactions on an antimalarial 1,2,4-triazolo[4,3-]pyrazine scaffold.

1,2,4-Triazolo[4,3-]pyrazines have previously been explored by the Open Source Malaria project as potent in vitro and in vivo antimalarial drug leads. With a view to generating a library of unique antimalarial 1,2,4-triazolo[4,3-]pyrazines and exploring regiochemical preference for nucleophilic amines, we utilised the known synthetic 5-chloro-3-(4-chlorophenyl)-[1,2,4]triazolo[4,3-]pyrazine () as a scaffold for aminations with 14 commercially available primary amines. Reacting scaffold with excess primary amine at room temperature for 16 h generated the desired amine analogues in respectable yields (18-87%) and high purity (≥95%) following chromatography workup.

Exploring the Utility of Cell-Penetrating Peptides as Vehicles for the Delivery of Distinct Antimalarial Drug Cargoes.

The devastating impact of malaria includes significant mortality and illness worldwide. Increasing resistance of the causative parasite, Plasmodium, to existing antimalarial drugs underscores a need for additional compounds with distinct modes of action in the therapeutic development pipeline. Here we showcase peptide-drug conjugates (PDCs) as an attractive compound class, in which therapeutic or lead antimalarials are chemically conjugated to cell-penetrating peptides.

Cheminformatics-Guided Exploration of Synthetic Marine Natural Product-Inspired Brominated Indole-3-Glyoxylamides and Their Potentials for Drug Discovery.

Marine natural products (MNPs) continue to be tested primarily in cellular toxicity assays, both mammalian and microbial, despite most being inactive at concentrations relevant to drug discovery. These MNPs become missed opportunities and represent a wasteful use of precious bioresources. The use of cheminformatics aligned with published bioactivity data can provide insights to direct the choice of bioassays for the evaluation of new MNPs.

Chemical and Antiplasmodial Investigations on -Derived Alkaloids and Semisynthetic Ether Analogues.

Microthecaline A (), the known antiplasmodial quinoline serrulatane alkaloid from the roots of F. Muell. ex Benth.

Semisynthesis and Cytotoxic Evaluation of an Ether Analogue Library Based on a Polyhalogenated Diphenyl Ether Scaffold Isolated from a Sponge.

The known oxygenated polyhalogenated diphenyl ether, 2-(2',4'-dibromophenoxy)-3,5-dibromophenol (), with previously reported activity in multiple cytotoxicity assays was isolated from the sponge sp. and proved to be an amenable scaffold for semisynthetic library generation. The phenol group of was targeted to generate 12 ether analogues in low-to-excellent yields, and the new library was fully characterized by NMR, UV, and MS analyses.

Solid-phase synthesis of Biotin-S-Farnesyl-L-Cysteine, a surrogate substrate for isoprenylcysteine Carboxylmethyltransferase (ICMT).

Inhibition of isoprenylcysteine Carboxylmethyltransferase (ICMT) is of particular interest as a potential target for the development of cancer chemotherapeutic agents. Screening for inhibitors of ICMT utilises a scintillation proximity assay (SPA) in which Biotin-S-Farnesyl-L-Cysteine (BFC) acts as a surrogate substrate. A solid-phase synthesis protocol for the preparation of BFC using 2-chlorotrityl chloride resin as a solid support has been developed to provide sufficient supply of BFC for high throughput screening (HTS) and subsequent chemistry campaigns to target inhibitors of ICMT.