A short and modular synthetic pathway using intramolecular 1,3-dipolar cycloaddition reactions and yielding functionalized isoxazoles, isoxazolines, and isoxazolidines is described. The change in shape of previous compounds and those in this study is quantified and compared using principal moment-of-inertia shape analysis.

the beta0diketone derivatives of nitroimidazole were synthesized from the reaction of magnesium salt of beta-ketoaccids 3 with imidazolide 4. the raction of beta-diketones with hydroxylamine hydrochloride afforded either the isoxazoles or the 5-hydroxyl-2-isoxazolines.

We have developed a new method of iodocyclization based on reagent-controlled oxidative aromatization. Our strategy takes advantage of the dual nature of iodine as both an iodinating and an oxidizing agent. This approach enabled "product switch" and enhanced the flexibility of the synthetic pathway toward pyrazoles and isoxazoles. In addition, the iodo moiety of the cyclized product could creat...

The beta0diketone derivatives of nitroimidazole were synthesized from the reaction of magnesium salt of beta-ketoaccids 3 with imidazolide 4. The raction of beta-diketones with hydroxylamine hydrochloride afforded either the isoxazoles or the 5-hydroxyl-2-isoxazolines.

An efficient, catalyst free, 1,3-dipolar cycloaddition strategy to conjugate nucleosides and nucleotides with isoxazoles under atmospheric conditions and in an aqueous environment is reported. The protocol involves chloramine-T as a practical reagent to induce in situ nitrile oxide formation and the alkyne partner is attached to the sugar residue or the nucleobase. The reactions are regiospecif...

Herein, we describe a short synthesis of 3-methyl-4-nitro-5-alkylethenyl isoxazoles and their reactivity as Michael acceptors. The title compounds reacted with nitromethane under phase-transfer catalysis to provide highly enantioenriched adducts (up to 93% ee) which were then converted to the corresponding γ-nitroacids.

The new 3,5-(substituted) pyrazoles and isoxazoles were prepared by reaction of (N'(1)E, N'(3)E)- N'(1), N'(3)-bis (3,4,5-substitutedbenzylidene)malonohydrazide with hydrazine hydrate and hydroxylamine hydrochloride respectively under solvothermal conditions involving an ecofriendly method without any environmental pollution, the yield are in the range of 75-96%. The structure of the new compou...

a series of curcumin derivatives containing heterocyclic moiety have been synthesized and evaluated for their antibacterial activities. the chemical structures of the synthesized compounds were verified on the basis of spectral data and elemental analyses. investigation of antimicrobial activity of the derivatives demonstrated the ability to inhibit gram-positive microorganisms with zone of inh...

Theoretical and experimental studies of the reaction of isoxazoles with diazo compounds show that the formation of 2H-1,3-oxazines proceeds via the formation of (3Z)-1-oxa-5-azahexa-1,3,5-trienes which undergo a 6π-cyclization. The stationary points corresponding to the probable reaction intermediates, isoxazolium N-ylides, were located by DFT calculations at the B3LYP/6-31G(d) level only for d...