A series of 9-alkylaminoacridines were synthesized and evaluated for activity against two strains of methicillin-resistant and one strain of methicillin-sensitive Staphylococcus aureus. Results are presented that show a clear structure activity relationship between the N-alkyl chain length and antibacterial activity with peak MIC99 values of 2-3 μM for alkyl chains ranging from 10 to 14 carbons in length. Although prior work has linked the function of acridine-based compounds to intercalation and topoisomerase inhibition, the present results show that 9-alkylaminoacridines likely function as amphiphilic membrane-active disruptors potentially in a similar manner as quaternary ammonium antimicrobials.
View Article and Find Full Text PDFToll-like receptors 7 and 8 (TLRs) have emerged as key targets in the design of small molecule adjuvants and stimulants for use in immunotherapies. This study examines the structure-activity relationship of a series of C2- and N1-substituted C7-methoxycarbonylimidazoquinolines to gain insight to the structural basis to TLR-7 and -8 selective activity. The analysis is further applied to evaluate the induction of multiple cytokines, including IL-10, IL-12, IL-1β, TNF-α, IFN-α, and IFN-γ, using murine BMDCs and human PBMCs.
View Article and Find Full Text PDFRe(VII) oxides catalyze the acetalization, monoperoxyacetalization, monothioacetalization and allylation of hemiacetals. The reactions, which take place under mild conditions and at low catalyst loadings, can be conducted using hemiacetals, the corresponding O-silyl ethers, and, in some cases, the acetal dimers. Aldehydes react under similar conditions to furnish good yields of dithioacetals.
View Article and Find Full Text PDFObjectives: Compounds characterized by a peroxidic skeleton are an interesting starting point for antischistosomal drug discovery. Previously a series of 3-alkoxy-1,2-dioxolanes, which are chemically stable cyclic peroxides, demonstrated significant in vitro activity against Plasmodium falciparum. We aimed to evaluate the potential of these compounds against Schistosoma mansoni and elucidate the roles of iron and peroxidic groups in activity.
View Article and Find Full Text PDFWe previously hypothesized that Staphylococcus epidermidis senses a diverse set of environmental and nutritional factors associated with biofilm formation through a modulation in the activity of the tricarboxylic acid (TCA) cycle. Herein, we report our further investigation of the impact of additional environmental stress factors on TCA cycle activity and provide a detailed description of our NMR methodology. S.
View Article and Find Full Text PDFA number of 3-alkoxy-1,2-dioxolanes exhibit promising levels of antimalarial activity against P. falciparum. A new route to the 1,2-dioxolane core is reported based on tandem peroxidation/cyclization of enones.
View Article and Find Full Text PDFThese data suggest that iron(II) reactivity for a set of homologous spiroadamantyl 1,2,4-trioxolane, 1,2,4-trioxane, and 1,2,4-trioxepane peroxide heterocycles is a necessary, but insufficient, property of animalarial peroxides. Heme alkylation efficiency appears to give a more accurate prediction of antimalarial activity than FeSO(4)-mediated reaction rates, suggesting that antimalarial activity is not merely dependent on peroxide bond cleavage, but also on the ability of reactive intermediates to alkylate heme or other proximal targets.
View Article and Find Full Text PDFOzonolysis of alkenes in the presence of solubilized water results in the direct formation of aldehydes and/or ketones, avoiding the need to isolate or decompose ozonides.
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