Determination of barbituric acid, utilizing a rapid and simple colorimetric assay

FeCl3·6H2O catalyzed aqueous media domino synthesis of 5-monoalkylbarbiturates: water as both reactant and solvent

Water as both reactant and solvent in a FeCl₃·6H₂O catalyzed domino reaction towards 5-monoalkylbarbiturates is described.

An efficient synthesis of novel dispirooxindole derivatives via one-pot three-component 1,3-dipolar cycloaddition reactions

A series of novel dispirooxindoles have been synthesized through three-component 1,3-dipolar cycloaddition of azomethine ylides generated in situ by the decarboxylative condensation of isatin and an α-amino acid with the dipolarophile 5-benzylidene-1,3-dimethylpyrimidine-2,4,6-trione. This method has the advantages of mild reaction conditions, high atom economy, excellent yields, and high regio- and stereo-selectivity.

Effect of some pyrimidine compounds on rat brain monoamine oxidase-B in vitro

The effects of some pyrimidine compounds (PCs) including barbituric acid (BA) 5,5-diethyl barbituric acid (DEBA), 2-thiobarbituric acid (TBA), violuric acid (VA), 2-thiouracil (TU), and 6-amino-2-thiouracil (ATU) on the activity of rat brain monoamine oxidase-B (MAO-B) were investigated. The results revealed that MAO-B was activated by BA, DEBA, TBA, TU, and ATU, and the activation was structural, concentration, and time dependent. However, MAO-B was inhibited by VA in a noncompetitive and irreversible manner with an enzyme-inhibitor dissociation constant (K (i) value) of 32 nM and IC(50) equals to 19 nM. All the studied PCs changed both the optimum pH and temperature of MAO-B.

Three-Component, One-Pot Sequential Synthesis ofN-Aryl,N‘-Alkyl Barbiturates§

[reaction: see text] Condensation between N-alkyl, N'-aryl carbodiimides and malonic acid monoesters leads to a high-yield formation of N-acyl urea derivatives that could be cyclized to C-monosubstituted barbiturates by addition of a suitable base in a one-pot sequential fashion. In the presence of an electrophile, the last step gives rise to a one-pot, three-component sequential synthesis of fully substituted barbiturates.

Spiro-annulation of barbituric acid derivatives and its analogs by ring-closing metathesis reaction

Barbituric acid 1 and related beta-dicarbonyl compounds were dialkenylated under the phase-transfer catalyst [e.g., benzyltriethylammonium chloride (BTEAC)] conditions to generate the diallylated products. These diallylated products were subjected to the ring-closing metathesis (RCM) reaction to deliver the corresponding spiro-annulated derivatives.

Spectrophotometric reaction rate method for determination of barbituric acid by inhibition of the hydrochloric acid-bromate reaction

A new kinetic-spectrophotometric method was developed for the determination of barbituric acid. The method is based on its inhibition effect on the reaction between hydrochloric acid and bromate. The decolorization of methyl orange by the reaction products was used to monitor the reaction spectrophotometrically at 510 nm. The variable affecting the rate of the reaction was investigated. The method is simple, rapid, relatively sensitive and precise. The limit of detection is 7.9x10(-7) M and calibration rang is 1x10(-6)-6.0x10(-4) M barbituric acid. The linearity range of the calibration graph is depends on bromate concentration. The relative standard deviation of seven replication determination of 5.6x10(-6) M barbituric acid was 1.8%. The influence of potential interfering substance was studied.