The UV-Vis and IR spectra of compounds 3 and 11 are shown in Table 2. Experimental UV-Vis and Fourier Transform Infrared Spectroscopy (FT-IR) Reaction of quinazolinthione with sodamide in methanol. The amide moiety (CONH) of 3-substituted quinazoline-2,4(1H,3H)-diones 11 and 13 was verified by 1H NMR spectra with a peak for the amidic proton at 11.47 and 10.87 ppm and by 13C NMR spectra with characteristic peaks at 162.20 and 160.90 ppm for the carbonyl groups with the disappearance of thioamide protons (CSNH) of 3-substituted 2-thioxo-2,3-dihydroquinazolin-4(1H)-ones 3 and 5 at 12.87 and 10.12 ppm and typical thione peaks at 175.50 and 176.50 ppm in 1H NMR and 13C NMR spectra, respectively (supplementary material (S1and S2)). Different spectral data as well as the X-ray crystallography of compound 11 were used to confirm 3-substituted quinazoline-2,4(1H,3H)-diones. The mechanism for the oxidation of quinazolinethione into the corresponding quinazolinedione may proceed through the formation of in situ generated sodium peroxide. To the best of our knowledge, the applicability of sodamide in the synthesis of quinazolinedione from quinazolinethione has not been reported (Table 1). ChemistryĪs a part of our ongoing program on the development of novel methods for organic synthesis under mild conditions, we describe a new efficient and practical route for the one-step conversion of 3-substituted 2-thioxo-quinazolin-4-ones ( 1– 8, Table 1) into the corresponding 3-substituted quinazolin-2,4-diones ( 9– 16, Table 1) using sodamide in methanol under mild conditions with high yields (79%–86% yield). Additionally, the spectroscopic interpretation of the synthesized compounds was performed based on ultraviolet-visible (UV-Vis), Fourier transform infrared spectroscopy (FT–IR) and nuclear magnetic resonance (NMR) spectral analysis. Furthermore, the X-ray crystallography of 6-methyl-3-phenylquinazoline-2,4(1H,3H)-dione ( 11) was performed, and the configuration of the substituents around the quinazolin-2,4-dione backbone was investigated. A considerably large amount of yields was afforded. In this study, a new simple methodology was used to oxidate the different quinazolin-2-thiones into the corresponding 2,4-quinazolindione this was achieved by heating the different quinazolin-2-thiones with sodamide in methanol. The crystal form of urea showed a planar conformation, indicating a network of hydrogen bonds. Moreover, urea molecule, which constitutes quinazolin-2,4-dione, was extensively studied experimentally and theoretically. Due to the biological importance of quinazolin-2,4-diones and 2-thioxo-quinazolin-4-ones, their molecular structures are studied by spectroscopic and theoretical methods. Moreover, quinazolinones, such as quinazolin-2,4-diones, and their corresponding 2-thioxo-quinazolin-4-ones undergo several biological activities, such as carbonic anhydrase, COX-1/2, tyrosine kinase inhibitions, and antitumor activity. The oxidation of thione compounds into the related carbonyl compounds was achieved using selenium oxide and tin oxides. Conversely, molecular oxygen and ozonation were used to oxidate thione into the corresponding ketones. Hydrogen peroxide and peroxy acids were used to oxidate different thioketones into the corresponding ketones.
The oxidation of thioamide into the corresponding amides was achieved using manganese dioxide, ceric ammonium nitrate, and copper nitrate. Potassium permanganate and lead tetra acetate were used to oxidize cyclic thiocarbonate into the corresponding carbonate. The oxidation of thiocarbonyl compounds into carbonyl compounds can be performed using different oxidative reagents. Diverse method for this conversion was developed, such as oxidative procedure by organic and inorganic reagents. The oxidation of thiones into carbonyl compounds has attracted the interest of organic chemists since the early 19 th century. In the crystal cell, two identical conformers of compound 11 were found connected by intramolecular hydrogen bonds, responsible for the favourable occurrence of these two independent molecules. The crystal structure of 6-methyl-3-phenylquinazoline-2,4(1H,3H)-dione ( 11) was determined. The structure of the newly synthesized compounds was determined by infrared spectroscopy, UV-visible spectroscopy, nuclear magnetic resonance, and single-crystal X-ray crystallographic analysis. A simple and efficient new synthetic method to obtain 3-substituted quinazolin-2,4-diones 9 –16 by the reaction of 3-substituted 2-thioxo-quinazolin-4-ones 1 – 8 with sodamide under mild conditions was presented.
0 kommentar(er)
