Publications by authors named "S A Visser"

Daprodustat, a novel oral hypoxia-inducible factor prolyl hydroxylase inhibitor is approved in the United States for the treatment of anemia due to chronic kidney disease (CKD) in adults receiving dialysis for at least 4 months. Pharmacodynamic dose-hemoglobin (Dose-Hgb) models were developed as daprodustat progressed through development. To support global phase III development, a dose-titration algorithm, guided by simulations from the initial Dose-Hgb model based on phase II clinical data, was implemented.

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CO capture is an important process for mitigating CO emissions in the atmosphere. Recently, ionic liquids have been identified as possible systems for CO capture processes. Major drawbacks of such systems are mostly in the high cost of synthesis of such liquids and poor biodegradability.

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The natural product synthesis of brevione J undergoes a cascade of reactions including an oxidative desaturation and a ring-expansion. The C-C desaturation of brevione B is catalyzed by the nonheme iron dioxygenase BrvJ using one molecule of O and α-ketoglutarate (αKG). However, whether the subsequent oxidative ring expansion reaction is also catalyzed by the same enzyme is unknown and remains controversial.

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Hypohalites are commonly generated in biological systems, mostly with functions related to defense and immune system response. These hypohalites can bind to metal centers and are known for their strong oxidizing properties that play crucial roles in various biological processes. Herein, we report the synthesis, characterization and reactivity of novel biomimetic Ru(III)-hypochlorite complexes and focus the work on the electronic effects associated with the incorporation of methyl groups in a pentadentate ligand framework in an asymmetric fashion.

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Nitrogenase is the enzyme primarily responsible for reducing atmospheric nitrogen to ammonia. There are three general forms of nitrogenase based on the metal ion present in the cofactor binding site, namely, molybdenum-dependent nitrogenases with the iron-molybdenum cofactor (FeMoco), the vanadium-dependent nitrogenases with FeVco, and the iron-only nitrogenases. It has been shown that the vanadium-dependent nitrogenases tend to have a lesser efficacy in reducing dinitrogen but a higher efficacy in binding and reducing carbon monoxide.

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