Coby
moleculeoftheday
Posts by this author
December 12, 2007
So people gush over bmim and get the guaranteed publications for including "ionic liquid" in the title of their article. Ionic liquids are far from the newest fad, though, they've been around for nearly 100 years!
93 years ago, Paul Walden reported that ethylammonium nitrate actually melts just…
December 11, 2007
Most metal ions will coordinate some electron-rich species in solution - water is a common suspect. Many other things can be hung off of certain metals, however, and an entire field and fame and fortune are available to those who manage to make something useful involving a metal. "Inorganic…
December 6, 2007
About 80 years ago, a scientist [pdf] wanted to learn about cholesterol metabolism. He took chicken feed and extracted it with organic solvent. In order make sure fat-soluble vitamins weren't left out, he added in cod liver oil (giving vitamins A and D, which were known). Then his unsuspecting…
December 4, 2007
Anaesthetics are weird. Much of what we use has a paucity of the oxygens and nitrogens that seems to make most drugs work, and there's been substantial puzzlement and handwringing over exactly how some of these things work. Xenon, for example, is a fine anaesthetic that is, of course, comprised of…
December 3, 2007
When you take organic chemistry, you learn about methyl iodide for putting on a methyl group. Eventually, though, if you stick with chemistry, you need an alkylating agent for grown-ups.
There's a lot of good ones, including dimethyl sulfate, methyl triflate (PDF), and the ever-so-toxic "magic…
November 30, 2007
A lot of science-fiction writers have spent a lot of time and energy hypothesizing silicon-based life. This isn't completely insane - if you go down a column of the periodic table, stuff tends to be the same. Fluorine, chlorine, bromine, and iodine all share properties, and so do carbon, silicon,…
November 29, 2007
DDQ is a benzoquinone derivative with some electron-withdrawing substituents, making it a bit more potent:
It's a bit more soluble than stuff like KMnO4, but not by much - it's a nightmare to work with.
November 27, 2007
In many parts of the world, what Westerners would call "meat alternatives" are the main source of protein. One such product is tempeh, made from soy. A particular variety, when contaminated with a particular bacterium, can become contaminated with a potent toxin: bongkrek acid.
Bongkrek acid,…
November 20, 2007
Marijuana is a puzzling drug, and a contentious one at that. Pure THC is sold pharmaceutically (and DEA-OK), but the whole plant isn't OK with the feds. That said, many states have decriminalized it for medical use. The pharmacology of cannabinoids is complex; marijuana aficionados report the drug…
November 19, 2007
Smoking cessation is tricky business - most of the time, people have used nicotine replacement therapy (the patch, the gum, etc) or CNS active drugs (like Wellbutrin/Zyban/Bupropion). None of it works that well - the manufacturers of today's molecule, Chantix, considered it news to brag about when…
November 15, 2007
Amino acids impart lots of functions to proteins, and a lot of the interesting chemistry happens at a few residues. Many hydrophobic residues like valine and leucine play a huge role - they don't like to touch water, and they help the protein fold, but the heavy lifting of catalysis happens in just…
November 14, 2007
Ethylene glycol dinitrate is simply the dinitrate ester of ethylene glycol - putting glycol under the same reaction conditions that yield the primitive nitro explosives, like nitroglycerin or TNT, yields this compound. Why's it important? It has a decent vapor pressure.
The volatility allows the…
November 13, 2007
Valencene is a citrus odorant found in the Valencia orange, hence its name:
It is a terpene, a motif that's ubiquitous in natural products.
November 9, 2007
I hadn't heard of this one before today: Mutagen X.
Mutagen X is apparently a byproduct of water chlorination, which isn't so surprising - chloroform (CHCl3) can occur in chlorinated water. This MX stuff is much worse, apparently. Anyone know the immediate source of the carbon?
November 7, 2007
There are a lot of stories bouncing around about a toy in Australia, Bindeez, which are apparently little beads that adhere to one another when you wet them. There are a ton of news sources getting very confused, but Reuters seems to have gotten it: they are contaminated with 1,4-butanediol, which…
November 5, 2007
As I've mentioned in the past, chemists often need to reduce a molecule by adding hydrogen. A medicinal chemist might get to an azide by way of an amine, or a food chemist might want to get to a saturated fat (or, although it's less and less popular, a trans fat).
Adding hydrogen can be done with a…
November 1, 2007
I've already talked about lead acetate and the fact that it was almost certainly the first artificial sweetener before, and I've been reading about it again lately. Here's something I didn't know - it may have helped cause the fall of Rome.
Here's how it worked. Roman households loved a condiment…
October 30, 2007
Lutein is just another carotenoid - like the previously covered retinal, it is a terpene.
Long, huh? That chain of alternating double and single bonds affords it its wonderful color. It, like retinal, plays a role in vision. The halloween angle is because it's one of the pigments in your pumpkin…
October 26, 2007
Mercury dissolves many metals. Put a little on normally steadfast aluminum and it will slowly eat it away. Mix it with some silver, copper, and other metals, and you've got a dental filling. Mix it with sodium, and you've got a great reducing agent.
Sodium amalgam acts much like sodium, but it's…
October 25, 2007
The term "rare earth metal" is a misnomer that's just stuck around. They haven't been rare for years - take this ad material from about 50 years ago at Theodore Gray's excellent Periodic Table Table site.
Didymium is a mixture of rare earth metals, which, when compounded with glass, imparts some…
October 24, 2007
As I've mentioned several times before, NMR is vital to modern chemistry (and medicine, for that matter).
Nb3Sn, or niobium-tin, is a superconductor that's used in modern high-field NMR (MRI) magnets.
October 23, 2007
Mischmetal is a mixture of a some rare earth metals, mostly cerium and lanthanum. The cerium, when finely divided, is pyrophoric - it burns.
When you mix mischmetal with some iron and magnesium oxides, it's a lot more brittle, and you can chip off little flakes, which give sparks. That's your…
October 19, 2007
Lewisite is nasty stuff - it's a compound of arsenic with two labile chlorines. As I mentioned yesterday, BAL is its antidote.
Lewisite is a chemical weapon from a particularly brutal era in this regard, and you hear about it a lot less these days. However, there's still plenty floating around...…
October 18, 2007
Lewisite is nasty stuff, which I'll cover tomorrow. Tonight, it's an antidote, which is simply the dithio analogue of glycerine. It enjoys the more colorful name of BAL, or British Anti-Lewisite.
BAL is an antidote to Lewisite. It's one of the few compounds that enjoys the use of a longish common…
October 17, 2007
Thiophene is a simple five-membered sulfur-containing heterocycle - it's the sulfur analogue of furan.
It's an interesting heterocycle in its own right but it's probably best known as a contaminant in benzene - almost all the bottles you get a hold of today proclaim they're "thiophene free."
It…
October 12, 2007
Diazolidinyl urea is a broad-spectrum biocide that is ubiquitous in cosmetics:
It does an admirable job. You'll see it EVERYWHERE once you start reading labels. It tends to be pretty benign, but a contact allergy can result, which makes it hard to find a usable suite of hygeine products for those…
October 11, 2007
DCMU is a simple aromatic molecule, and a pretty specific electron acceptor for the photosystem II protein found in plants. What does this mean?
Electron transfer reactions are important in all of life; plants use it in photosynthesis. Some DCMU will kill your plants nicely, and it's a broad-…
October 10, 2007
Uracil mustard is a mimic of the RNA component and DNA precursor uracil, and it also has a few reactive ends that can do some damage.
Those chlorines amount to very reactive ends; the idea here is that they're hopefully a little better targeted than generally toxic molecules like the plain old…
October 9, 2007
Retene is an aromatic molecule that occurs when forest fires happen - burning trees makes it.
The isopropyl is a dead giveaway for a terpene, which are ubiquitous among natural products (and their forest-fire synthesized derivatives).
It makes a picrate, too!
October 8, 2007
Picric acid is a simple enough organic acid - its nitro groups withdraw electrons, making it a pretty strong acid for a phenol. However, it's got a slightly darker side: it's to TNT what phenol is to toluene. Those nitroes come with a price.
Picric acid is funny; like raney nickel, it's much more…