We herein report the conventional and microscale parallel synthesis of selective inhibitors of human blood coagulation factor XIIa and thrombin exhibiting a 1,2,4-triazol-5-amine scaffold. Structural variations of this scaffold allowed identifying derivative 21i, a potent 29 nM inhibitor of FXIIa, with improved selectivity over other tested serine proteases and also finding compound 21m with 27 nM inhibitory activity toward thrombin. For the first time, acylated 1,2,4-triazol-5-amines were proved to have anticoagulant properties and the ability to affect thrombin- and cancer-cell-induced platelet aggregation. Performed mass spectrometric analysis and molecular modeling allowed us to discover previously unknown interactions between the synthesized inhibitors and the active site of FXIIa, which uncovered the mechanistic details of FXIIa inhibition. Synthesized compounds represent a promising starting point for the development of novel antithrombotic drugs or chemical tools for studying the role of FXIIa and thrombin in physiological and pathological processes.

Herein we report a microscale parallel synthetic approach allowing for rapid access to libraries of N‐acylated aminotriazoles and screening of their inhibitory activity against factor XIIa (FXIIa) and thrombin, which are targets for antithrombotic drugs. This approach, in combination with post‐screening structure optimization, yielded a potent 7 nM inhibitor of FXIIa and a 25 nM thrombin inhibitor; both compounds showed no inhibition of the other tested serine proteases. Selected N‐acylated aminotriazoles exhibited anticoagulant properties in vitro influencing the intrinsic blood coagulation pathway, but not extrinsic coagulation. Mechanistic studies of FXIIa inhibition suggested that synthesized N‐acylated aminotriazoles are covalent inhibitors of FXIIa. These synthesized compounds may serve as a promising starting point for the development of novel antithrombotic drugs.

A fast and fully automated method for chiral analysis has been developed by combining a chiral derivatization approach with high-resolution trapped ion mobility separation. Although the presented approach can be potentially applied to diverse types of chiral compounds, several benchmark amino acids were used as model compounds, focusing on the smallest amino acid alanine. An autosampler with an integrated chromatography system was used for inline chiral derivatization with (S)-naproxen chloride and subsequent preseparation. Afterwards, derivatized amino acids were directly introduced into the electrospray interface of a trapped ion mobility–mass spectrometer for rapid diastereomer separation in the gas phase. This unique combination of preseparation and trapped ion mobility spectrometry separation in the negative ion mode enabled rapid chiral analysis within 3 min per sample. Furthermore, the diastereomer separation proved to be independent of alkali salts or other metal ions, offering robustness with regard to samples containing high amounts of salts. Highly sensitive detection of amino acid diastereomers was possible down to the lower nanomolar concentration range, and enantiomeric ratios could be readily determined from the recorded mobilograms with excellent reproducibility and precision. To demonstrate the general applicability of our method, alanine and other amino acids were analyzed from soy sauces and seasonings, which revealed extraordinarily high d-Ala contents of up to 99% in all samples.

In this study, the combination of speciation analysis and native mass spectrometry is presented as a powerful tool to gain new insight into the diverse interactions of environmentally relevant organotin...

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