Synthesis and properties of 5-substituted 2-thiobarbituric acid dyes

Akiyama, Shuzo; Nakashima, Kenichiro; Nakatsuji, Shin’ichi; Suzuki, Mari; Umekawa, Chiemi

doi:10.1016/0143-7208(87)85037-4

Cited by 15 publications

(4 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Aromatic aldehydes stand out in the flavor profile of fruit and essential oils. Their reaction with TBA led to arylidene-2-thiobarbituric acids (Guille ´n- Sans et al, 1985;Guille ´n-Sans, 1986;Akiyama et al, 1987;Guille ´n-Sans and Guzma ´n-Chozas, 1988b-d). Many of these derivatives melt with decomposition above 300 °C, and they dissolve easily in alkali and protophilic solvents.…”

Section: Resultsmentioning

confidence: 99%

Spectrophotometric Profiles of Off-Flavor Aldehydes by Using Their Reactions with 2-Thiobarbituric Acid

Guzmán-Chozas

Vicario

Guillén-Sans

1997

J. Agric. Food Chem.

View full text Add to dashboard Cite

The reaction of flavor aldehydes with 2-thiobarbituric acid (TBA) and the factors affecting this reaction have been studied. The formation rate of the 530−532 nm absorption band for detecting food rancidity through the TBA assay was dependent on the type of aldehyde and the reaction conditions. TBA reacted slowly with alkanals, and the yellow pigment (450 nm) was formed. Only after 1 h of heating at 100 °C was the red pigment formed. With 2-alkenals the reaction rate was more favorable for the red adduct (530−532 nm) formation, especially in excess TBA reagent and by employing an adequate heating time at 100 °C (water bath). For 2,4-dienals the orange pigment (494 nm) formation prevailed; the formation of the red adduct underwent a slow development (5 h at least). The development of the red adduct was favorable in an acetic acid concentration of 15−25% v/v. The yellow pigment was the only one that developed (although slowly) in glacial acetic acid medium. Keywords: Aldehydes; flavor; rancidity; 2-thiobarbituric acid (TBA)−aldehyde pigments; 2-thiobarbituric acid (TBA) assay

show abstract

Section: Resultsmentioning

confidence: 99%

Spectrophotometric Profiles of Off-Flavor Aldehydes by Using Their Reactions with 2-Thiobarbituric Acid

Guzmán-Chozas

Vicario

Guillén-Sans

1997

J. Agric. Food Chem.

View full text Add to dashboard Cite

show abstract

“…The reaction mixture was refluxed for 20 h. An orange precipitate was formed and recrystallized from DMF/ EtOH to give orange crystals of 2,2Ј-bis(N5-phenyl-4,6-dihydroxy-5-pyrimidinecarbothioamide) 11 (0. 25 …”

Section: Reaction Of 12-dihydro-2-thioxo-46(1h5h)pyrimidinedione 1mentioning

confidence: 97%

Novel Reaction Products from Thiobarbituric Acid of Biological Interest

Aly

Mourad

Hassan

et al. 2004

Archiv der Pharmazie

View full text Add to dashboard Cite

The reactions of 1, 2-dihydro-2-thioxo-4, 6(1H, 5H)pyrimidinedione (1) with some pi-deficients have led to the formation of unexpected heterocyclic products such as anilinomethylenethioxopyrimidinedione, 2, 2'-bis(pyrimidinecarbothioamide), allylthioxopyrimidinecarbothioamide, indenopyranopyrimidine and benzofuropyrimidine derivatives. A possible mechanism for the formation of these products is discussed, and the biological activity is determined.

show abstract

“…In particular, such dyes are readily accessible via Knoevenagel condensation of corresponding (thio)barbituric acid derivatives with 4-N,N-dimethylaminocinnamaldehyde, and the preparation of compounds 4, 6, and 7 has been previously reported. 39,[46][47][48][49] Note that dyes 4, 6, and 7 have found interest as nonlinear optic materials, 50 as methionine aminopeptidase-1 inhibitors 49 and laser dyes. 51 Further, interactions of heavy metal ions with compound 7 39 including its application as photoconductor for electrophotography [52][53][54] or dye in hair tinting lotions were described, while comprehensive structural data (e.g.…”

Section: Introductionmentioning

confidence: 99%