The study of tautomerics equilibria is vital importance as tautomeric compounds reactivity highly depends on the proportion each tautomer. Herein, equilibrium 3-phenyl-2,4-pentanedione was studied theoretically by b3lyp/6-31+g(d)methods. effect four solvents considered (water, methanol, carbon tetrachloride and Cyclohexane).The takes place through four-membered ring transition state. barrier he...

The title Schiff base compound, C25H19NO2S, crystallizes in a statistically disordered structure comprising keto and enol tautomeric forms. In the enol form, the benzenoid arrangment is promoted by a strong intra-molecular O-H⋯N hydrogen bond and adopts an E conformation about the imine bond. In the keto form there is an intramolecular N-H⋯O hydrogen bond. In the crystal, an extended network of...

TExcited state reaction coordinates and the consequent energy profiles of a new Schiff base, N-salicilydenemethylfurylamine (SMFA), have been investigated with the MP2 and CASSCF method. The potential energy profiles of the ground and the lowest excited singlet state are calculated. The excited state potential energy profile shows a small barrier in the LIIC pathway of dissociation along the O-...

Recently, a new generation of highly promising inhibitors bearing β-keto-enol functionality has emerged. Reported herein is the first synthesis and use of novel designed drugs based on the β-keto-enol group embedded with heterocyclic moieties such as pyrazole, pyridine, and furan, prepared in a one-step procedure by mixed Claisen condensation. All the newly synthesized compounds were characteriz...

BACKGROUND Several papers described the structure of curcumin and some other derivatives in solid and in solution. In the crystal structure of curcumin, the enol H atom is located symmetrically between both oxygen atoms of the enolone fragment with an O···O distance of 2.455 Å, which is characteristic for symmetrical H-bonds. In the solution, the geometry of the enolone fragment is attributed t...

2-((2-Hidroksibenziliden)amino)-4-nitrofenol Schiff bazı bileşiğinin konformasyon analizi; DFT yönteminde, B3LYP metodu ve 6-311G++(d,p) temel seti ile yapılmış bileşiğin cis trans izomerlerinin konformasyonları teorik olarak hesaplanarak en kararlı konformasyonlar belirlenmiştir. Toplam enerjileri dihedral açıları keto enol formlarının tautomer kararlılıkları Enol formundaki molekülün formuna ...

Abstract The 13 C NMR chemical shifts of the three Edaravone tautomers (keto, enol, and amine) were calculated using a combined molecular mechanics (Pcmod 9.1/MMFF94) ab initio (GIAO (B3LYP/DFT, 6–31 + G(d)) model. This method gave such good agreement with experiment that assignment complex spectrum in solution, which is mixture could be made. has been attempted previously by various methods di...

The electrochemical cathodic reduction of cyclic imides (maleimides) to succinimides can be achieved chemoselectively in the presence of alkene, alkyne, and benzyl groups. The efficiency of the system was demonstrated by using a 3D electrode in a continuous flow reactor. The reduction of 3,4-dimethylmaleimides to the corresponding succinimides proceeds with a 3:2 diastereomeric ratio, which is ...

Capillary Gas Chromatography (CGC) is capable of determining underivatized cyclophosphamide (CPA) using SCOT OV 275 columns. Then CPA is subjected to in situ degradation resulting in formation of a cyclization product which can be determined selectively in biological fluids. In routine bioanalysis however cyclization products of CPA metabolites might interfere, e.g. 4-keto CPA. In the present s...