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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:
Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...
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 .
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]
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class and is the most commonly consumed psychoactive substance globally. [ 9 ] [ 10 ] It is mainly used for its eugeroic ( wakefulness promoting), ergogenic (physical performance-enhancing), or nootropic (cognitive-enhancing) properties.
This article contains a list of organs in the human body. It is widely believed that there are 79 organs (this number goes up if you count each bone and muscle as an organ on their own, which is becoming a more common practice [1] [2]); however, there is no universal standard definition of what constitutes an organ, and some tissue groups' status as one is debated. [3]
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.
Paraxanthine is the primary metabolite of caffeine in humans and other animals, such as mice. [3] Shortly after ingestion, roughly 84% of caffeine is metabolized into paraxanthine by hepatic cytochrome P450 , which removes a methyl group from the N3 position of caffeine.