The emerging field of small-molecule-drug conjugates (SMDCs) using small-molecule biomarker-targeted compounds for tumor homing may provide new perspectives for targeted delivery. Here, for the first time, we disclose the structure and the synthesis of VIP236, an SMDC designed for the treatment of metastatic solid tumors by targeting αvβ3 integrins and extracellular cleavage of the 7-ethyl camptothecin payload by neutrophil elastase in the tumor microenvironment. Imaging studies in the Lewis lung mouse model using an elastase cleavable quenched substrate showed pronounced elastase activity in the tumor.
View Article and Find Full Text PDFActivated coagulation factor XI (FXIa) is a highly attractive antithrombotic target as it contributes to the development and progression of thrombosis but is thought to play only a minor role in hemostasis so that its inhibition may allow for decoupling of antithrombotic efficacy and bleeding time prolongation. Herein, we report our major efforts to identify an orally bioavailable, reversible FXIa inhibitor. Using a protein structure-based design approach, we identified a novel micromolar hit with attractive physicochemical properties.
View Article and Find Full Text PDFAfter acute myocardial infarction, early reperfusion is the most effective strategy for reducing cardiac damage and improving clinical outcome. However, restoring blood flow to the ischemic myocardium can paradoxically induce injury by itself (reperfusion injury), with microvascular dysfunction being one contributing factor. α adrenergic receptors have been hypothesized to be involved in this process.
View Article and Find Full Text PDFDespite advances in the treatment of heart failure in recent years, options for patients are still limited and the disease is associated with considerable morbidity and mortality. Modulating cyclic guanosine monophosphate levels within the natriuretic peptide signaling pathway by inhibiting PDE9A has been associated with beneficial effects in preclinical heart failure models. We herein report the identification of BAY-7081, a potent, selective, and orally bioavailable PDE9A inhibitor with very good aqueous solubility starting from a high-throughput screening hit.
View Article and Find Full Text PDFDespite extensive research on small molecule thrombin inhibitors for oral application in the past decades, only a single double prodrug with very modest oral bioavailability has reached human therapy as a marketed drug. We have undertaken major efforts to identify neutral, non-prodrug inhibitors. Using a holistic analysis of all available internal data, we were able to build computational models and apply these for the selection of a lead series with the highest possibility of achieving oral bioavailability.
View Article and Find Full Text PDFIdiopathic pulmonary fibrosis (IPF) is a rare and devastating chronic lung disease of unknown etiology. Despite the approved treatment options nintedanib and pirfenidone, the medical need for a safe and well-tolerated antifibrotic treatment of IPF remains high. The human prostaglandin F receptor (hFP-R) is widely expressed in the lung tissue and constitutes an attractive target for the treatment of fibrotic lung diseases.
View Article and Find Full Text PDFA method for the coupling of aryl chlorides and thiophenols using an air-stable nickel(0) catalyst is described. This thioetherification procedure can be effectively applied to a range of electronically diverse aryl/heteroaryl chlorides without more expensive metal catalysts such as palladium, iridium, or ruthenium. This investigation also illustrates both, a variety of thiol coupling partners and, in certain cases, the use of CsCO.
View Article and Find Full Text PDFAn efficient and divergent methodology for the synthesis of new anthracenone-pyranones and anthracenone-furans is described. Key reactions discussed in these syntheses include an aldehyde promoted annulation with a β-keto-sulfoxide, a domino alkyne insertion/carbonylation/Nu-acylation and a DMEDA promoted Castro-Stephens reaction. We also report the in vitro growth inhibition of these compounds in a range of human cancer cells.
View Article and Find Full Text PDFA domino alkyne addition/CO insertion/Nu acylation reaction to a series of novel anthrapyran-2-ones in good to excellent yields is described. In addition, an efficient synthetic sequence involving carbonylation, formation of a β-keto-sulfoxide, and cyclization is presented en route to the antibiotic and antitumor compound (±)-BE-26554A.
View Article and Find Full Text PDFShall we dance? Within the proposed mechanism for the palladium-catalyzed title reaction, the strained alkene norbornene (or norbornadiene) enters and exits the catalytic cycle in a catalytic "square dance", acting as both a promoter and a coupling partner in the formation of four carbon-carbon bonds, two of them by challenging C--H activation processes.
View Article and Find Full Text PDFThe first total synthesis of the proposed structure of delta-indomycinone has been accomplished. The key steps involve the Diels-Alder reaction of a bromonaphthoquinone (6) and 1-methoxy-3-methyl-1-trimethylsiloxy-1,3-butadiene (7) to access the anthraquinone skeleton, representing a common building block of other naturally occurring anthraquinone antibiotics, regioselective bromination of anthraquinone (14) and a highly diastereoselective alkylation of enantiomerically pure dioxolanone 8. The reported synthetic approach has the advantage of high yields, excellent selectivity and a remarkable general applicability for the total synthesis of other anthrapyran natural products.
View Article and Find Full Text PDFTwo high-yielding strategies for the synthesis of 4H-anthra[1,2-b]pyran antibiotics have been developed giving access to novel antitumor agent (ED(50) 1.5 microm) and to (S)-espicufolin (3). A key step for the assembly of the tetracyclic 4H-anthra[1,2-b]pyran-4,7,12-trione skeleton is the nucleophilic addition of an aryl lithium species onto an aldehyde which allows the introduction of either an ynone or 1,3-diketo side chain, serving as precursors for an acid-catalysed cyclisation.
View Article and Find Full Text PDFThe first total synthesis of (R)-gamma-indomycinone has been achieved which allowed the determination of the configuration of the stereogenic center of natural gamma-indomycinone as (S). The approach stands out for its generality and efficiency. [reaction: see text]
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