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Xanthine (/ ˈ z æ n θ iː n / or / ˈ z æ n θ aɪ n /, from Ancient Greek ξανθός xanthós ' yellow ' for its yellowish-white appearance; archaically xanthic acid; systematic name 3,7-dihydropurine-2,6-dione) is a purine base found in most human body tissues and fluids, as well as in other organisms. [2]
Methylxanthines are chemical compounds which are derivatives of xanthine with one or more methyl groups, including: One methyl group: 1-Methylxanthine; 3-Methylxanthine; 7-Methylxanthine; Two methyl groups: Theophylline (1,3-dimethylxanthine) Paraxanthine (1,7-dimethylxanthine) Theobromine (3,7-dimethylxanthine) Three methyl groups:
Paraxanthine is not known to be produced by plants [1] but is observed in nature as a metabolite of caffeine in animals and some species of bacteria. [2]Paraxanthine is the primary metabolite of caffeine in humans and other animals, such as mice. [3]
Nathanson concluded that caffeine and related methylxanthines could be natural pesticides developed by plants as protection against worms: Caffeine is found in many plant species, with high levels in seedlings that are still developing foliage, but are lacking mechanical protection; [17] caffeine paralyzes and kills certain insects feeding upon ...
The plant contains chemicals that are toxic to animals including humans, but it has also been used as a medicine. All parts of the plant contain protoanemonin , which can cause severe skin and gastrointestinal irritation, bitter taste and burning in the mouth and throat, mouth ulcers, nausea, vomiting, diarrhea, and hematemesis .
7-Methylxanthine (7-MX), also known as heteroxanthine, is an active metabolite of caffeine (1,3,7-trimethylxanthine) and theobromine (3,7-dimethylxanthine). [ 1 ] [ 2 ] It is a non-selective antagonist of the adenosine receptors .
The characteristic signals, distinguishing theophylline from related methylxanthines, are approximately 3.23δ and 3.41δ, corresponding to the unique methylation possessed by theophylline. The remaining proton signal, at 8.01δ, corresponds to the proton on the imidazole ring, not transferred between the nitrogen.
Alkaloid-containing plants have been used by humans since ancient times for therapeutic and recreational purposes. For example, medicinal plants have been known in Mesopotamia from about 2000 BC. [30] The Odyssey of Homer referred to a gift given to Helen by the Egyptian queen, a drug bringing oblivion.