Multi-Component synthesis and computational studies of three novel thio-barbituric acid carbohydrate derivatives

• Compounds 1, 2 and 3 were synthesized by condensation reaction.
• Compounds 1, 2 and 3 were characterized with the help of 1H, 13C, 2D experiments.
• The experimental 1H, 13C NMR values correlated with calculated values.
• Intramolecular interactions and ellipticity analyzed by AIM approach.
• The computational calculations were done using DFT/B3LYP/6-311G + (d, p) methods.

The thio-barbituric acid is convenient starting compound for the preparation of fused heterocycles and its 5-substituted derivatives which are pharmacologically one of the most important classes of compounds. The fused compounds of thio-barbituric acid, 4-(1R,2S,3S,4S)-1,2,3,4,5-tetrahydroxy pentyl-10-phenyl-1,3,6,8,9,10 hexahydro-2,7-dithiooxopyrido [2,3-d; 6,5'] dipyrimidine-4,5 diones (1), 4-(1S,2S,3S,4S)-1,2,3,4,5-tetrahydroxy pentyl-10-phenyl-1,3,6,8,9,10 hexahydro-2,7-dithiooxopyrido [2,3-d; 6,5'] dipyrimidine-4,5 diones (2), 3-(1R,2S,3S)-1,2,3,4-tetrahydroxy butyl-10-phenyl-1,3,6,8,9,10 hexahydro-2,7-dithiooxopyrido [2,3-d; 6,5'] dipyrimidine-4,5 diones (3) have been synthesized in single step by the condensation of thio-barbituric acid with sugars (l-rhamnose, l-fucose and l-arabinose) & aniline using para-toluene sulfonic acid (p-TSA) as an effective acid catalyst under refluxing conditions. The molecular structure and detailed spectroscopic analysis of all three novel synthesized thiones derivatives have been performed using experimental techniques like 1H, 13C NMR, 2D (COSY, HSQC, DEPT-135 and DEPT-90) as well as theoretical calculations by density functional theory (DFT) using B3LYP and 6-311G + (d, p) basis set. The strength and nature of weak intramolecular interactions have been studied by atom in molecule (AIM) approach. Global reactivity descriptors have been computed to predict reactivity and reactive sites in the molecule.

The three novel thio-barbituric acid carbohydrate derivatives tetrahydro-2,2'-thioxopyrimidin-4,4'-diones (1), (2) and (3) were synthesized and characterized by 1H, 13C, HMBC, HSQC, DEPT-90, DEPT-135, COSY spectrometry. Quantum chemical calculations have been performed at DFT level of theory using B3LYP functional and 6-311 G + (d, p) basic set using Gaussian 09 software package.Figure optionsDownload as PowerPoint slide