Paraxanthine is an inhibitor of phosphodiesterase 9 (PDE9) and an antagonist of adenosine receptors A1 and A2 (Kis = 35 and 22 μM, respectively in equine forebrain tissues). It is the main metabolite of caffeine in humans, making up 80% of the three dimethylxanthine metabolites produced by caffeine demethylation. Paraxanthine increases locomotor activity and counteracts adenosine receptor agonist-induced motor depression in rats not habituated to caffeine. At a dose of 30 mg/kg, paraxanthine induces a significant increase in striatal cGMP and extracellular striatal dopamine concentrations in vivo. It also promotes wakefulness and increases locomotor activity and core temperature in narcoleptic transgenic mice without increasing behavioral anxiety.
Off-White to Pale Yellow Solid
1,7-Dimethylxanthine has been used for the quantification of caffeine by high-performance liquid chromatography (HPLC).
Paraxanthine is an adenosine receptor ligand and a major metabolite of caffeine.This compound is a contaminant of emerging concern (CECs).
adenosine receptor agonist, CNS stimulant
ChEBI: 1,7-dimethylxanthine is a dimethylxanthine having the two methyl groups located at positions 1 and 7. It is a metabolite of caffeine and theobromine in animals. It has a role as a central nervous system stimulant, a human xenobiotic metabolite, a human blood serum metabolite and a mouse metabolite.
1,7-Dimethylxanthine (Paraxanthine) has been shown to have several of the same nootropic benefits as caffeine, including improved cognition, short-term memory, sustained attention in healthy adults and beneficial cognitive effects in animal models of Parkinson’s disease. Moreover, the beneficial impacts on physical endurance and sports performance observed with caffeine use have also been suggested for paraxanthine. Mechanistically, some of these effects are mediated by a similar mechanism for caffeine and paraxanthine, which act as antagonists of adenosine receptors A1 and A2a. Despite these similarities in mechanisms, it has been reported that there are potential differences in adenosine receptor binding affinity, as paraxanthine exhibited higher binding potencies for adenosine A1 and A2A receptors in equine forebrain and a stronger locomotor activating effect in rats relative to caffeine. Furthermore, paraxanthine, but not other methylxanthines (caffeine, theobromine, theophylline), has been shown to potentiate nitric oxide neurotransmission, which has been associated with increased blood flow and subsequent changes in aerobic exercise performance and cardiovascular health.
Paraxanthine is a major plasma and urinary metabolite of caffeine. This xanthine derivative is, along with caffeine, a central nervous system stimulant. This Snap-N-Spike? reference solution is applicable for caffeine quantitation in clinical toxicology or urine drug testing by LC-MS/MS or GC/MS.
Adenosine receptor ligand; major metabolite of caffeine
An experimental teratogen. Mutation data reported. Whenheated to decomposition it emits toxic fumes of NOx.
Paraxanthine (1,7-dimethylxanthine) is a metabolite of caffeine that can be found naturally in small amounts in some foods, including green coffee beans, cotyledonary leaves of Coffea arabica, Theobroma cacao fruits, roasted coffee beans, citrus flowers and Sicilian orange flower honey. However, it is predominantly found as the major metabolite of caffeine, accounting for approximately 70%–72% of ingested caffeine[1].
