MDA-9/Syntenin, a key scaffolding protein and a molecular hub involved in a diverse range of cell signaling responses, has proved to be a challenging target for the design and discovery of small molecule probes. In this paper, we report on the design and synthesis of small molecule ligands of this key protein. Genetic algorithm-based computational design and the five–eight step synthesis of three molecules led to ligands with affinities in the range of 1–3 µM, a 20–60-fold improvement over literature reports. The design and synthesis strategies, coupled with the structure-dependent gain or loss in affinity, afford the deduction of principles that should guide the design of advanced probes of MDA-9/Syntenin.

Nature offers a variety of structurally unique, sulfated endobiotics including sulfated glycosaminoglycans, sulfated tyrosine peptides, sulfated steroids/bile acids/catecholamines. Sulfated molecules display a large number of biological activities including antithrombotic, antimicrobial, anticancer, anti‐inflammatory, and others, which arise from modulation of intracellular signaling and enhanced in vivo retention of certain hormones. These characteristics position sulfated molecules very favorably as drug‐like agents. However, few have reached the clinic. Major hurdles exist in realizing sulfated molecules as drugs. This state‐of‐the‐art has been transformed through recent works on the development of sulfate masking technologies for both alkyl (sulfated carbohydrates, sulfated steroids) and aryl (sTyr‐bearing peptides/proteins, sulfated flavonoids) sulfates. This review compiles the literature on different strategies implemented for different types of sulfate groups. Starting from early efforts in protection of sulfate groups to the design of newer SuFEx, trichloroethyl, and gem‐dimethyl‐based protection technologies, this review presents the evolution and application of concepts in realizing highly diverse, sulfated molecules as candidate drugs and/or prodrugs. Overall, the newer strategies for sulfate masking and demasking are likely to greatly enhance the design and development of sulfated molecules as non‐toxic drugs of the future.

Only a handful of anticoagulants have reached the clinic to treat and prevent thrombotic episodes in the millions of patients suffering from cardiovascular, cancer, viral (COVID-19) and metabolic diseases. In this work, we report the discovery, chemical synthesis, mechanistic biochemistry, pharmacology, and toxicology of SB-01, a novel, allosteric, human factor XIa (FXIa) inhibitor that displays potent antithrombotic activity in preclinical models. SB-01 is a synthetic, highly sulfated, aromatic agent that binds in both anion-binding exosites of hFXIa to induce inhibition of factor IX activation. SB-01 inhibited rodent arterial and venous thrombosis at doses of 6 and 3 mg/kg, respectively. Additionally, a twice-a-day regimen of 6 mg/kg SB-01 was significantly more effective (p<0.001) in preventing deep vein thrombosis in animals with lung cancer. Michaelis-Menten kinetics and competition with unfractionated heparin and polyphosphate revealed SB-01 to be an allosteric inhibitor. Critically, at the effective dose of 6 mg/kg, SB-01 did not significantly increase mouse tail bleeding time or blood loss. Further, SB-01's anticoagulation could be readily reversed with protamine sulfate, the FDA-approved antidote for heparin. Finally, SB-01 showed no major adverse effects across multiple toxicological assays including gross, cardiac, metabolic, hematological, and clinical chemistry. Overall, this work presents a structurally and functionally unique, allosteric small molecule as a highly promising candidate for safer anticoagulation.

We present a novel one-step methodology for direct mass spectrometric characterization of sulfated non-saccharide glycosaminoglycan mimetics in their sodiated form using trifluorodiazoethane that enables separation and detection in a LC-MS system.