Recent Advances in the Application of Barbituric Acid Derivatives in Multicomponent Reactions

Barbituric acid is a pyrimidine heterocyclic organic compound, which is pharmacologically active. It is important to build structures containing various medicinal activities. This compound attracts the scientific research community in organic synthesis. It can be used in the synthesis of polyheterocyclic, natural, medicinal compounds, and organic sensors. Herein, the utilization of barbituric or thiobarbituric acid in multicomponent reactions is reported from 2016-2021 in this manuscript.

Reduced Molecular Flavins as Single-Electron Reductants after Photo-Excitation

Flavoenzymes mediate a multitude of chemical reactions and are catalytically active both in different oxidation states and in covalent adducts with reagents. The transfer of such reactivity to the organic laboratory using simplified molecular flavins is highly desirable and such applications in (photo-)oxidation reactions are already established. However, molecular flavins have not been used for the reduction of organic substrates yet, although this activity is known and well-studied for DNA photolyase enzymes. We report a catalytic method using reduced, molecular flavins as photo-reductants and γ-terpinene as sacrificial reductant. Additionally, we present our design for air-stable, reduced flavin catalysts, which is based on a conformational bias strategy and circumvents the otherwise rapid reduction of O2 from air. Using our catalytic strategy, we were able to replace super-stoichiometric amounts of the rare-earth reductant SmI2 in a 5-exo-trig cyclization of substituted barbituric acid derivatives. Such flavin-catalyzed reductions are anticipated to be of broad applicability and their straightforward synthesis indicates future use in stereo- as well as site-selective transformations.

As Antimicrobial Agents: Synthesis, Structural Characterization and Molecular Docking study of Barbituric Acid Derivatives from Phenobarbital

In spite of phenobarbital has been used in various medical fields as hypnotics, anxiolytics, and anticonvulsants, it also contains active functional groups that can be reacted to form other products as dyes, polymers, antimicrobial and anti-antioxidants agents. A series of barbituric acid derivatives containing 1,2,3,4-Tetrazoline moiety were synthesized from phenobarbital. Phenobarbital 1 as raw starting material was reacted with acrylonitrile compound to give diacetonitrile derivative 2, this compound was treated in two ways, urea and thiourea to form barbituric acid derivatives containing oxadiazole and thiadiazole ring 3, 4 respectively. The Schiff bases derivatives 5, 6 (a-c) were synthesized from reacting the latter compounds with three aromatic aldehydes. In the final step, the barbituric acid derivatives containing 1,2,3,4Tetrazoline moiety 7, 8 (a-c) were prepared by cycloaddition reaction between different Schiff bases derivatives and sodium azide. The compounds were characterized by Melting point, 13 C-NMR, 1 H-NMR and FTIR techniques. Also, the result compounds were tested against two kinds of bacteria and two kinds of fungi. Most of the prepared derivatives were showed a high and clear effect against different types of bacteria and fungi. Molecular docking of final barbituric acid derivatives 7, 8 (a, b) were investigated with Molegro Virtual Docker (MVD).

An Efficient Microwave-Assisted Synthesis Method of Novel Bi2O3 Nanostructure and Its Application As a High-Performance Nanocatalyst in Preparing Benzylidene Barbituric Acid Derivatives

In this study, controllable and optimal microwave irradiation has been used to synthesize the novel nanostructures of Bi2O3 under environmental conditions. The final products had a thermal stability of 210 °C, an average particle size distribution of 85 nm, and surface area of 783 m2/g. The high thermodynamic stability of Bi2O3 nanostructures were confirmed by TG and DSC analyses. The nanostructure nature of compounds, most importantly, the use of effective, cost effective and rapid synthesis route of microwave have created significant physiochemical properties in the Bi2O3 products. These unexpected properties have made the possibility of potentials application of these products in various fields, especially in nanocatalyst applications. It is well-documented that, as Lewis acid, bismuth nanocatalyst exhibits a great catalytic activity for the green synthesis of some bio-active barbituric acid derivatives using precursors with electron-donating or –withdrawing nature in high yields (80-98%). After incorporating this catalyst into the aqueous media, all the reactions were completed within 2-3 min at room temperature. The main advantages of this method are practical facility, the availability of starting materials, and low costs besides the catalyst reusability. Additionally, the catalyst synthesis process may be carried in the aqueous media during a short period with medium to high yields. The obtained results have opened a new window for development of a novel nanocatalyst with practical application.

Barbiturates: A Review of Synthesis and Antimicrobial Research Progress

Background: Barbituric acid and its derivatives have turned heads for several years as an indispensable class of compounds in the pharmaceutical industry because of their vast assortment of biological activities such as anticonvulsants, hypnotics, anti-diabetic, antiviral, anti-AIDS, anti-cancer, anti-microbial and anti-oxidant etc. Plethoras of studies have shed light on the properties, synthesis, and reactivity of these compounds. The depiction of multiple biological activities by barbiturates compelled us and by virtue of which herein we have mediated over the progress of synthesis of numerous kinds of compounds derived from barbituric acid with well-known and typical examples from 2016 to the present. Objective: The review focuses on the advancements in methods of synthesis of barbituric acid derivatives and their applications as antimicrobial agents. Conclusion: This review will help future researchers to analyze the previous studies and to explore new compounds for the development of efficient antimicrobial drugs.