Showing chemical card for Dihydrothymine (CFc000000056)
Record Information
Version
1.0
Creation Date
2022-08-28 10:25:12 UTC
Update Date
2022-09-13 18:44:21 UTC
Chemfont ID
CFc000000056
Molecule Identification
Common Name
Dihydrothymine
Definition
Dihydrothymine (CAS: 696-04-8) is an intermediate breakdown product of thymine. Dihydropyrimidine dehydrogenase catalyzes the reduction of thymine into 5,6-dihydrothymine; then dihydropyrimidinase hydrolyzes 5,6-dihydrothymine into N-carbamyl-beta-alanine. Finally, beta-ureidopropionase catalyzes the conversion of N-carbamyl-beta-alanine into beta-alanine. When present at abnormally high levels, dihydrothymine can be toxic, although the mechanism of toxicity is not clear. In particular, patients with dihydropyrimidinase deficiency exhibit highly increased concentrations of 5,6-dihydrouracil and 5,6-dihydrothymine; and moderately increased concentrations of uracil and thymine can be detected in urine. Dihydropyrimidinase deficiency is a disorder that can cause neurological and gastrointestinal problems in some affected individuals. The most common neurological abnormalities that occur are intellectual disability, seizures, weak muscle tone (hypotonia), abnormally small head size (microcephaly), and autistic behaviours that affect communication and social interaction. Gastrointestinal problems that occur in dihydropyrimidinase deficiency include the backflow of acidic stomach contents into the esophagus (gastroesophageal reflux) and recurrent episodes of vomiting.
Belongs to the class of organic compounds known as hydropyrimidines. Hydropyrimidines are compounds containing a hydrogenated pyrimidine ring (i.E. Containing less than the maximum number of double bonds.).
Yamane, Tetsuo; Wyluda, Benjamin J.; Shulman, Robert G. Dihydrothymine from ultraviolet-irradiated DNA. Proceedings of the National Academy of Sciences of the United States of America (1967), 58(2), 439-42.
