Search results for "isoxazoline"

Mpro-SARS-CoV-2 Inhibitors and Various Chemical Reactivity of 1-Bromo- and 1-Chloro-4-vinylbenzene in [3 + 2] Cycloaddition Reactions

2021

The regioselectvity and the mechanism of the (32CA) cycloadditions reactions of 1-bromo-4-vinylbenzene 1 and 1-chloro-4-vinylbenzene 2 with benzonitrile oxide 3 were investigated under the molecular electron density theory (MEDT) at the B3LYP/6-311++G(d,p) computational level. Evaluation of the ELF reveals that these zwitterionic type (zw-type) 32CA reactions take place in a two-stage one-step mechanism. This MEDT study shows that the meta isoxazolines are kinetically and thermodynamically favored over the ortho ones, these 32CA reactions being completely regioselective, in agreement with experimental outcomes. In addition, the efficiency of isoxazolines against SARS-CoV-2 have been also in…

Modified Carbon Nanoforms Systems for Asymmetric Catalysis

SYNTHESIS AND APPLICATIONS OF NOVEL FULLERENES AND SILSESQUIOXANES BASED STRUCTURES

2020

CaCl2, Bisoxazoline, and Malonate: A Protocol for an Asymmetric Michael Reaction

2015

A mild protocol for the asymmetric Michael addition of dimethyl malonate to various α,β-unsaturated carbonyl compounds was developed. The salient feature of this methodology is that a cheap and environmentally friendly Lewis acid, CaCl2, was used as a catalyst. An aminoindanol- and pyridine-derived ligand provided in the presence of CaCl2 Michael adducts in moderate to high enantioselectivities. The scope of the reaction was demonstrated.

The structural aspects of the transformation of 3-nitroisoxazoline-2-oxide to 1-aza-2,8-dioxabicyclo[3.3.0]octane derivatives: Experimental and MEDT …

2019

Abstract Reaction of 3-nitroisoxazoline-2-oxide with monosubstituted ethenes, first time documented fifty years ago, have been reviewed. Structures of phenyl and cyano derivatives of 1-aza-2,8-dioxabicyclo[3.3.0]octane produced in [3 + 2] cycloaddition (32CA) between styrene and acrylonitrile with 3-nitroisoxazoline-2-oxide were determined through single crystal XRD analysis. The molecular mechanism of the title 32CA has been also analyzed within the Molecular Electron Density Theory (MEDT) based on the M06-2X(PCM)/6-311 + G(d,p) calculations.

Bisoxazoline-Fullerene Hybrid Systems for Asymmetric Catalysis

Development of novel dipeptide-like rhodesain inhibitors containing the 3-bromoisoxazoline warhead in a constrained conformation.

2015

Novel dipeptide-like rhodesain inhibitors containing the 3-bromoisoxazoline warhead in a constrained conformation were developed; some of them possess K(i) values in the micromolar range. We studied the structure-activity relationship of these derivatives and we performed docking studies, which allowed us to find out the key interactions established by the inhibitors with the target enzyme. Biological results indicate that the nature of the P2 and P3 substituents and their binding to the S2/S3 pockets is strictly interdependent.

Development of rhodesain inhibitors with a 3-bromoisoxazoline warhead

2013

Novel rhodesain inhibitors were obtained by combining an enantiomerically pure 3-bromoisoxazoline warhead with a specific peptidomimetic recognition moiety. All derivatives behaved as inhibitors of rhodesain, with low micromolar Ki values. Their activity against the enzyme was found to be paralleled by an in vitro antitrypanosomal activity, with IC50 values in the mid-micromolar range. Notably, a preference for parasitic over human proteases, specifically cathepsins B and L, was observed.

Synthesis of highly functionalized β-aminocyclopentanecarboxylate stereoisomers by reductive ring opening reaction of isoxazolines

2012

A rapid and simple procedure was devised for the synthesis of multifunctionalized cyclic β-amino esters and γ-amino alcohols via the 1,3-dipolar cycloaddition of nitrile oxides to β-aminocyclopentenecarboxylates. The opening of the isoxazoline reductive ring to the corresponding highly functionalized 2-aminocyclopentanecarboxylates occurred stereoselectively with good yields.

Crystal structure of 5-(4-tert-butoxyphenyl)-3-(4-n-octyloxyphenyl)-4,5-dihydroisoxazole

2019

The molecule of the title compound, C27H37NO3, was prepared by [3 + 2] 1,3-dipolar cycloaddition of 4-n-octylphenylnitrile oxide and 4-tert-butoxystyrene, the latter compound being a very useful intermediate to the synthesis of liquid-crystalline materials. In the molecule, the benzene rings of the n-octyloxyphenyl and tert-butoxyphenyl groups form dihedral angles of 2.83 (7) and 85.49 (3)°, respectively, with the mean plane of the isoxazoline ring. In the crystal, molecules are linked by weak C—H...O hydrogen interactions into chains running parallel to the b axis.