INTRODUCTION Advances in NMR technology over the last 20 years have made information on solution structures of proteins increasingly available. High-resolution solution structures of proteins as large as 20-25 kDa are tractable in most cases, and recent advances allowed Kay to solve the structure of an 82 kDa protein. These advances in NMR analysis of protein structure have made possible the st...

Succinimidinium hydrogensulfate ([H-Suc]HSO4), as a new and stable derivative of succinimide, is easily prepared by the reaction of succinimide with neat sulfuric acid. This ionic liquid can be used as an efficient catalyst for the acetylation of alcohols, phenols, thiols and amines at room temperature under mild and solvent free conditions. All the products are separated and identified using d...

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 wi...

Some oxime ether derivatives of α-ionone (4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-one) have been synthesized. Reaction of 4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-ketoxime with various chloro and fluoro aromatic and hetero aromatic compounds gave the corresponding oxime ether derivatives via aromatic nucleophilic substitution (SNAr). The structures of these co...

Molecular modeling analysis of charge density and heat of fornation by PM3 method as well as C, H NMR and 2D-NMR measurements of histidine (substrate) and some of its derivatives as histidine decarboxylase inhibitors were performed. It was established that the atom, usually nitrogen, which forms internal aldimine with pyridoxal5 -phosphate (PLP), (coenzyme), has negative and almost equal ...

Chemical shifts (CS) of the ¹H nucleus in N···H···O type hydrogen bonds (H-bond) were observed in some complexes between chlorophenols [pentachlorophenol (PCP), 2,4,6-tricholorophenol (TCP), 2,6-dichlorophenol (26DCP), 3,5-dichlorophenol (35DCP), and p-chlorophenol (pCP)] and nitrogen-base (N-Base) by solid-state high-resolution ¹H-NMR with the magic-angle-spinning (MAS) method. Employing N-Bas...

The temperature-dependent ‘H and 13C NMR spect_ra of (hS-C.r.~Hs)3Rh3 (CO)C6H&sC6Hs support the view that this molecule is fluxional in solution at room temperature but is in a frozen conformation at -88”; NMR data of (h’-CsHs)sRh3 (CO) CeFsCsC6F5 indicate that this molecule appears to be static at room temperature and fluxional at elevated temperatures. The NMR data are consistent with structu...

A SO3 H-containing solid acid namely SO3 H-functionalized phthalimide (SFP) was synthesized from phthalimide and chlorosulfonic acid, and identified by studying its FT-IR, 1 H and 13C NMR, Mass, XRD, TG and DTG spectra. Afterward, its catalytic activity was examined for the solvent-free condensation of dimedone (5,5-dimethyl-1,3-cyclohexanedione) (2 eq.) with arylaldehydes (1 eq.). The results ...