Receptors. In their Communication (e202216011), Jan J. Weigand et al. report the selective separation of lithium, magnesium, and calcium using 4-phosphoryl pyrazolones as pH-regulated receptors.

The first organocatalytic Michael-cyclization cascade reaction between isothiocyanato oxindoles and unsaturated pyrazolones has been developed. The multicyclic spiro[oxindole/thiobutyrolactam/pyrazolone] core structures containing three contiguous stereogenic centers, including two spiro quaternary centers, were prepared with excellent diastereo- (up to >20 : 1) and enantioselectivities (up to ...

Sulfonated polymer-based materials, among heterogeneous catalysts, are frequently utilized in chemical transformations due to their outstanding and physical durability. In this regard, a magnetic sulfonated melamine–formaldehyde resin (MSMF) catalyst was successfully prepared from mixture of Fe3O4 nanoparticles two steps. MSMF used as for the one-pot, three-component condensation benzyl pyrazol...

The tautomerism of 1-phenyl-1,2-dihydro-3H-pyrazol-3-One was investigated. An X-ray crystal structure analysis exhibits dimers of 1-phenyl-1H-pyrazol-3-ol units. Comparison of NMR (nuclear magnetic resonance) spectra in liquid state (¹H, 13C, 15N) with those of "fixed" derivatives, as well as with the corresponding solid state NMR spectra reveal this compound to exist predominantly as 1H-pyrazo...

An efficient synthesis of spiropyrazolones based on organocatalysis is described. The reaction between pyrazolones, enolizable aldehydes and enals is catalyzed by secondary amine catalysts and affords the final spiro compounds bearing four contiguous chiral centers in good yields and excellent diastereo- and enantioselectivities.

The first organocatalytic double Michael cascade reaction between unsaturated ketones and unsaturated pyrazolones has been developed which provides spiropyrazolone core structures containing two interval or three consecutive stereogenic centers with excellent diastereo- (>20:1) and enantioselectivities (up to 99% ee). Moreover, a pair of enantiomers and can be achieved via different catalysts.

The N-heterocyclic carbene (NHC)-organocatalyzed enantioselective annulation reaction of pyrazolones with α,β-unsaturated aldehydes proceeding via the chiral α,β-unsaturated acyl azolium intermediates under oxidative conditions is presented. The reaction afforded dihydropyranone-fused pyrazoles in moderate to good yields and good er values under operationally simple and base-free conditions.

Amyotrophic lateral sclerosis (ALS) is a progressive and ultimately fatal neurodegenerative disease. Pyrazolone containing small molecules have shown significant disease attenuating efficacy in cellular and murine models of ALS. Pyrazolone based affinity probes were synthesized to identify high affinity binding partners and ascertain a potential biological mode of action. Probes were confirmed ...