2-amino-substituted ketones react with α-methylene ketones under solvent-free conditions at 90 °c in thepresence of a catalytic amount of zirconium dodecylphosphonate to create the corresponding quinolinesin excellent yields. this procedure recommends numerous advantages such as easy work-up, use of mild,reusable and safe catalyst, short reaction timeand high yields. the new compounds have been...

in this research, so3h-functionalizedphthalimide (sfp) has been prepared through simple reaction of phthalimide with chlorosulfonic acid, and characterized using ft-ir, 1h nmr, 13c nmr, sem (scanning electron microscopy), mass and tg (thermal gravimetric) spectra. afterward, the solid acid has been utilized as an efficient, green, heterogeneous and recyclable catalyst for the solvent-free synth...

(‒)-Encecanescin (1) has been isolated from the leaves of Eupatorium aschembornianum. Two conformers are present in the crystal structure as a result of molecular disorder. The structure of 1 was established by 1H- and 13C-NMR spectroscopy in CDCl3 solution using 2D NMR techniques (gHSQC, gHMBC and NOESY). A Monte Carlo random search using molecular mechanics followed by the geometry optimizati...

Assignment of the fifteen carbons of terrecyclic acid A, C15H20O3, a new sesquiterpene antibiotic, in the 13C NMR spectrum was performed by 13C-[1H] selective proton decoupling experiments, comparison with spectra of its derivatives and chemical shifts.

the imine intermediate generated by the addition of primary amine to the cinnamaldehyde is trapped by the n-isocyaniminotriphenylphosphorane (ph3pnnc) and a carboxylic acid, and leads to the formation of the corresponding iminophosphorane intermediate. the 1,3,4-oxadiazole derivatives are formed via intramolecular aza-wittig reaction of the iminophosphorane intermediate. the reactions were comp...

a general synthetic route to the synthesis of imidazoles has been developed using nano sbcl5/sio2 under solvent-free conditions. the multi-component reactions of aldehydes, benzil and ammonium acetate were carried out to afford some trisubstituted imidazole derivatives. this method provides several advantages like simple work-up, environmentally benign, and shorter reaction times along with hig...

Iso-butyric acid as a new, simple, and expensive solvent/catalyst was successfully used for the chemoselective Fischer’s synthesis of indolenines derivatives 3a-r by one-pot condensation reaction of various phenylhydrazines 1a-e with the substituted acetophenones 2a-c at reflux conditions. In this protocol, all products 3a-r were obtained in high yields and short reaction time. The structures o...

High-resolution magic angle spinning (HR-MAS) one- and two-dimensional 1H and 13C nuclear magnetic resonance (NMR) spectroscopy has been used to study intact glioblastoma (GBM) brain tumour tissue. The results were compared with in vitro chemical extract and in vivo spectra. The resolution of 1H one-dimensional, 1H TOCSY and 13C HSQC HR-MAS spectra is comparable to that obtained on perchloric e...

In the structural analysis of lignins by 13C-NMR, signal overlap limits definitive assignment and accurate inten­ sity measurement. Selective labeling by 13C-enrichment of a specific carbon in lignin enhances its signal intensity in the spectrum. Further enhancement of the specifically labeled carbons can be realized via difference spectra created from the enriched and unenriched samples. Diffe...

The hepatic metabolism of 1,omega-dodecanedioic acid, a physiologically relevant representative of the medium-chain dicarboxylic acid family, has been studied by a combination of in vivo and in vitro 13C and 1H NMR spectroscopic techniques. Rats in different nutritional or hormonal situations were infused with [1,12-13C2]- or [1,2,11,12-13C4]dodecanedioic acid, and the kinetics of 13C label app...