In this work, stable crystalline phosphorus yields are obtained in good yields from the 1:1:1 addition reactions between hydrazine derivatives and dialkyl acetylenedicarboxylates in the presence of triphenylphosphine at room temperature in dichloromethane. This synthetic method has merits of high yields, mild reaction conditions, and simple experimental and work-up conditions. The obtained yiel...

Vitamin C (ascorbic acid) concentrations in whole blood obtained by finger prick or by venipuncture have been shown to be equivalent when measured by the 2,4-dinitrophenylhydrazine procedure. Whole blood obtained by eithertechnique is stable for at least 6 h at 25#{176}C, and for as long as 28 days when stabilized with trichloroacetic acid and stored at 4#{176}C. Storage of whole blood at -70#{...

Objective: This study was designed to examine the potential protective effects of Rheum ribes L., and quercetin on protein carbonyl (PCO) in kidney liver tissue, trace elements (Fe, Cu, Zn) mineral (P) serum samples Wistar rats carbon tetrachloride (CCl4)-induced oxidative damage. 
 Methods: The 2, 4-dinitrophenylhydrazine (DNPH) method is most reliable widely used measure levels proteins....

Ascorbate Determination, 2,4-Dinitrophenylhydrazine Microamounts of vitamin C could be readily determined in 20 ul-samples using the 2,4-dinitrophenylhydrazine method together with separation by thin layer chromato­ graphy. The condensation reaction was carried out for 5 min at 100 °C on a glass fibre disc. Purification of vitamin C hydrazones was accomplished by repeated separation on TLC plat...

To develop a quick method for the preliminarily screening of mutant strains that can accumulate 9α-hydroxyandrost-4-ene-3,17-dione (9α-OH-AD), a high-throughput screening method was presented by applying the principle that 2,4-dinitrophenylhydrazine (DNPH) can react with ketones to produce precipitation. The optimal color assay conditions were the substrate androst-4-ene-3,17-dione (AD) concent...

INTRODUCTION Because of its chemical diversity, the only way to standardise propolis is to specify multiple standards for different propolis types according to the corresponding chemical profile. So far, this has been done only for European propolis. OBJECTIVE To develop a rapid low-cost spectrophotometric procedure for quantification of bioactive prenylated flavanones in Taiwanese propolis. ...

Vitamin C is L-xyloascorbic acid (ascorbic acid, AA). Its first oxidation product is dehydroascorbic acid (dehydroAA) which also possesses vitamin C activity, possibly because of the ease with which many animal tissues can reduce it back to AA (Grimble & Hughes, 1967). AA and dehydroAA may be referred to as ‘total vitamin C’. T h e determination of AA, or of AA and dehydroAA, is central to all ...