A new class of bradykinin 1 receptor antagonists containing the piperidine acetic acid tetralin core

Rh-Catalyzed Annulation of Enaminones with Maleimides for Functionalized Aza-spiro α-Tetralones and Benzo[e]isoindoles via C-H Activation/C═C Bond Cleavage

An unprecedented strategy for Rh-catalyzed C-H activation/C═C bond cleavage of enaminones is described for the construction of biologically interesting aza-spiro α-tetralones and benzo[e]isoindoles. This protocol provides diversely functionalized aza-spiro α-tetralones and benzo[e]isoindoles in good yields via a [4 + 2] annulation of the exomaleimides and maleimides. This strategy displays a good substrate scope, outstanding functional group tolerance, and excellent regioselectivity.

Bradykinin and Neurotensin Analogues as Potential Compounds in Colon Cancer Therapy

Colorectal cancer (CRC) is one of the most lethal malignancies worldwide, so the attempts to find novel therapeutic approaches are necessary. The aim of our study was to analyze how chemical modifications influence physical, chemical, and biological properties of the two peptides, namely, bradykinin (BK) and neurotensin (NT). For this purpose, we used fourteen modified peptides, and their anti-cancers features were analyzed on the HCT116 CRC cell line. Our results confirmed that the spherical mode of a CRC cell line culture better reflects the natural tumour microenvironment. We observed that the size of the colonospheres was markedly reduced following treatment with some BK and NT analogues. The proportion of CD133+ cancer stem cells (CSCs) in colonospheres decreased following incubation with the aforementioned peptides. In our research, we found two groups of these peptides. The first group influenced all the analyzed cellular features, while the second seemed to include the most promising peptides that lowered the count of CD133+ CSCs with parallel substantial reduction in CRC cells viability. These analogues need further analysis to uncover their overall anti-cancer potential.

Spectroscopic characterization and in vitro studies of biological activity of bradykinin derivatives

Eleven multiple analogs of bradykinin-a peptide that is a natural ligand of B1 and B2 receptors but does not bind or activate the B1 receptor unless Arg⁹ is removed from the sequence by the action of carboxypeptidase N-were synthesized. Their biological activity was examined on T-REx cell lines expressing B1 or B2 receptors using the intracellular IP1 assay. The mRNA expression of B1R and B2R in the lysate of tumor cell lines, e.g., U87-MG (human astrocytoma), SHP-77 (human small cell lung cancer), and H4 (human brain glioma), was determined. For five B1R antagonists, adsorption at the liquid/solid interface (Au nanoparticles (AuNPs) served as the solid surface) was discussed in terms of the vibrations of molecular fragments (structural factors) responsible for the biological properties of these analogs.

Visible-Light-Promoted Multistep Tandem Reaction of Vinyl Azides toward the Formation of 1-Tetralones

A visible-light-driven multistep tandem reaction between vinyl azides and alkyl bromides has been developed leading to the formation of tetralone skeletons under mild conditions, which can be easily scaled up to the gram scale. Various 1-tetralone derivatives are synthesized and transformed into desired products in good to high yields.

Ring-Expansion Approaches for the Total Synthesis of Salimabromide

We describe the evolution of a synthetic strategy for the construction of the marine polyketide salimabromide. Combining a bicyclo[3.1.0]hexan-2-one ring-expansion to build up a functionalized naphthalene and an unprecedented rearrangement/cyclization cascade, enabled synthesis of a dearomatized tricyclic subunit of the target compound. Alternatively, an intramolecular ketiminium [2+2]-cycloaddition and subsequent Baeyer-Villiger ring-expansion gave access to the sterically encumbered architecture of salimabromide. Sequential oxidation of the carbon framework finally enabled the total synthesis of this unusual natural product.

A facile and regioselective synthesis of 1-tetralones via silver-catalyzed ring expansion

A regioselective synthesis of 1-tetralones via silver-catalyzed ring expansion is described.

Aryl sulfonamides containing tetralin allylic amines as potent and selective bradykinin B1 receptor antagonists

The bradykinin B1 receptor has been shown to mediate pain response and is rapidly induced upon injury. Blocking this receptor may provide a promising treatment for inflammation and pain. We previously reported tetralin benzyl amines as potent B1 antagonists. Here we describe the synthesis and SAR of B1 receptor antagonists with homobenzylic amines. The SAR of different linkers led to the discovery of tetralin allylic amines as potent and selective B1 receptor antagonists (hB1 IC(50)=1.3 nM for compound 16). Some of these compounds showed modest oral bioavailability in rats.

Targeting the bradykinin B1 receptor to reduce pain

The bradykinin B1 receptor is an inducible G-protein-coupled receptor. It is induced or upregulated at the site of inflammation or injury. A large body of preclinical data supports the development of B1 antagonists as novel therapeutics for the treatment of pain and inflammation. The necessary in vitro and in vivo drug discovery tools are currently available to evaluate novel B1 antagonists. Two major classes of small-molecule B1 antagonists, arylsulfonamide-based and biphenyl-based B1 antagonists, have been disclosed in the last few years.