ˇmuchos tacos! for the excellent primer -- this brings back memories of how orderly the nomenclature of organic chemistry is. It has always appealed to the obsessive-compulsive nature in me ;-) (but I'm serious about my thanks)
Stephen Beecroft wrote: > Quick recap and primer for all interested parties (or should I say, both > interested parties): > > Xanthine (ZAN-theen) is purine with oxygens bonded in the 2 and 6 > positions, that is, 2,6-dihydroxypurine. Ronn also referred to this as > 2,6-dioxopurine and as purine-2,6-dione, apparently following alternate > (I would guess older) nomenclatures. Structurally, it's actually a > fairly small, simple molecule. See > http://www.serva.de/products/data/38420.01.shtml for details. > > If you take xanthine and bond methyl groups (CH3) to it, you get a > family of substances called (unsurprisingly) methylxanthines. If you > bond three methyls in the 1, 3, and 7 positions, you get > 1,3,7-trimethylxanthine, also called caffeine. This is the best-known of > the methylxanthines, which share some similar physiological properties. > > If you bond only two methyl groups instead of three, you get a related > but slightly different molecule. Exactly which molecule you get depends > on where you put the methyls: > > If you bond the two methyls to the 3 and 7 positions, you get > theobromine, which Ronn tells us is the primary methylxanthine found in > chocolate. Thus, when people tell you that "chocolate doesn't contain > any caffeine", they are technically correct, though wrong in spirit. > Theobromine differs chemically from caffeine only by a single methyl > group, and its stimulant properties are not dissimilar. > > If you bond the two methyls to the 1 and 3 positions, you get > theophylline (1,3-dimethylxanthine), which Ronn tells us is more common > in tea than in coffee or chocolate. It's also an asthma treatment > because it's a bronchodilator, something Stacy apparently realizes. Ronn > tells us that regular old caffeine can be used in a pinch as a > bronchodilator, as well. > > If you bond the two methyls to the 1 and 7 positions, which was Ronn's > "missing" family member, you get paraxanthine, or 1,7-dimethylxanthine. > Unsurprisingly, this is a major caffeine metabolite, which is to say > that this is one of the chemicals produced by your body when it breaks > down caffeine. It's also identified as an adenosine receptor ligand, > which means it ties itself to certain receptor sites. By the way, that's > typically how psychoactive drugs work -- they attach themselves to > various receptor sites. > > Does this mean that paraxanthine is a psychoactive drug? I don't know; > maybe. Perhaps other xanthines or methylxanthines act as adenosine > receptor ligands. Maybe that's ultimately how caffeine produces its > effects on the brain. In any case, now you have some idea about caffeine > (found in coffee) and three closely related chemicals, theobromine > (found in chocolate), theophylline (found in tea), and paraxanthine > (found in Starbucks customers). > > Stephen -- Marc A. Schindler Spruce Grove, Alberta, Canada -- Gateway to the Boreal Parkland “Man will occasionally stumble over the truth, but most of the time he will pick himself up and continue on” – Winston Churchill Note: This communication represents the informal personal views of the author solely; its contents do not necessarily reflect those of the author’s employer, nor those of any organization with which the author may be associated. ////////////////////////////////////////////////////////////////////////////// /// ZION LIST CHARTER: Please read it at /// /// http://www.zionsbest.com/charter.html /// ///////////////////////////////////////////////////////////////////////////// ==^^=============================================================== This email was sent to: archive@jab.org EASY UNSUBSCRIBE click here: http://topica.com/u/?aaP9AU.bWix1n.YXJjaGl2 Or send an email to: [EMAIL PROTECTED] T O P I C A -- Register now to manage your mail! http://www.topica.com/partner/tag02/register ==^^===============================================================
