Stacy.
At 05:59 AM 11/17/2002 +0000, you 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 ////////////////////////////////////////////////////////////////////////////// /// ZION LIST CHARTER: Please read it at /// /// http://www.zionsbest.com/charter.html /// ///////////////////////////////////////////////////////////////////////////// --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.399 / Virus Database: 226 - Release Date: 10/09/2002
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