Everyone has heard of superglue. If it weren’t so entrenched in everyone’s mind as something that existed, you’d be absolutely amazed. Whenever I am at Wal-Mart, a drug store, a dollar store, or anywhere that has the six two-gram tubes of superglue for a dollar, I compulsively grab at least one, usually shaking my bemused shopping mate or getting one on the phone (”Guess what I just found at Wal-Mart?!” “The six tubes of superglue again, huh?” “Don’t patronize me, it’s AMAZING!”). I have tolerant friends.

Superglue is a trade name (probably a generic name, by now, I guess, considering my vast superglue collection is definitely not all marketed by the same company) for a class of adhesives called “cyanoacrylates.” The superglue you buy at the store is typically either methyl or ethyl cyanoacrylate. Another cyanoacrylate adhesive, 2-octyl cyanoacrylate, is available to seal wounds. I’ve heard it’s commercially available as “dermabond,” but I’ve never seen it, even in the suture cabinet back when I volunteered in a hospital for a few years. You can be sure I will own some someday.

Read the rest of this entry »

The last, fastest spot on the chromatograph is FD&C Blue #1, or Brilliant Blue FCF:

Read the rest of this entry »

When cannibis was first being studied, the active principle was isolated and found to be delta-9-tetrahydrocannabinol, shown below. Later on, studies showed that there were, in fact, endogeneous receptors that interacted with the compound. In abundance. We termed it the cannabinoid receptor, for lack of a better word. Endogeneous or not, the only thing we knew that would fit in it came from a drug of abuse!
This was baffling: Nature tends to be pretty parsimonious. A truly vestigial receptor class was unlikely. So did we evolve in the (continuous) presence of dope fields? Surely not. This was a strong indication that there was some sort of endogeneous cannabinoid. The search was on. Despite having known about marijuana for literal millenia, we didn’t find an endogenous ligand until 1992! This came out of Raphael Mechoulam’s lab - the same guy who isolated THC back in 1964! To be fair, even though THC was long-since discovered, we only knew about cannabinoid receptors as recently as 1988.

Read the rest of this entry »

99 years ago, a Japanese researcher was looking into some puzzling stuff. A broth of kelp, when boiled down, yielded some brown crystals that tasted like, well, essence of savoriness. “Savory” is one of those flavors that is hard to pinpoint - for salty, sweet, sour, bitter, we have archetypes - sugar, sodium chloride, lemon juice, and alkaloids, which you don’t taste on their own very often. As Barry Sharpless noted, he won’t taste a compound with a nitrogen atom in it - these are the bulk of our alkaloids, many of which are psychotropic (not nearly all, though). The best everyday example of a bitter compound I can think of is tonic water, which is bitter due to the alkaloid quinine.

Anyway, savoriness, or “umami,” as he put it, is hard to pinpoint. Those crystals he found came close, which were those of the much-maligned monosodium glutamate, or MSG:

Read the rest of this entry »

Lead is one of the most familiar heavy metals to people. Disquieting is the fact that so many people haven’t handled it because of all the concern about its toxicity. Fishing weights are increasingly being replaced with heavy but less-toxic alternatives, like bismuth.

If you’ve never handled lead, please try it. I worry that it will go the way of mercury and you just won’t be able to get it in ten years. I can get all sorts of weird stuff in a chemistry building, but you don’t really have that luxury. It is soft and magic. If you have it in bar form you can bend it like Superman. It will make your week. Just wash your hands afterwards, and don’t store it in the butter dish.
Enter one of my heroes, Theodore Gray, with his Periodic Table Table. His entry on lead does the element more justice than I will. He also notes a few places you can get lead: hardware stores, fishing stores, and Wal-Mart. With lead’s wide use in plumbing, it probably won’t go away as quickly as I claim (the symbol for lead, Pb, comes from the latin plumbum. as you might expect, this is where the word plumbing comes from).

Lead is a lot like mercury - toxic, but not so terrible. You can handle lead pretty freely - for instance, I’d hold lead in my hands, not mercury. You can dent it with your fingernail. It’s surprisngly heavy, but not as heavy as gold or tungsten. Like mercury, the soluble compounds are much worse. One is Lead (II) acetate:

Read the rest of this entry »

Here’s a quacky one for you. If you lived through the 70’s, you remember this as Laetrile. Amygdalin is a cyanide compound found in almond, peach pits, and some other stone fruits. Fun fact: “amygdala,” like in your brain, comes from the same Greek root as amygdalin. Here, it describes the source of the compound, in “amygdala,” it describes the shape of the structure. Sort of like naming the pituitary “Mr. Peanut,” then translating it into a dead tongue for some added class.

Read the rest of this entry »

This is the yellow pigment in turmeric, the spice responsible for curries being nuclear holocaust yellow.

Read the rest of this entry »

Here’s a neat and weekend-appropriate one. I’ve alluded to the fact that your body processes small amounts of endogenous alcohol in the course of metabolism. As such, you have evolved some enzymes to process ethanol. The enzymes are meant for ethanol, since that’s what organisms saw for the most part in the course of evolution. As we’ve seen with drugs and poisons, though, other molecules can fit just fine into the active pocket of an enzyme and it can do its business on them, too. Sometimes this works in your favor, sometimes not. In the case of alcohol, it’s great. If you didn’t have a processing enzyme, it would be much more harmful than it is; it would have to wait around to pass through your urine (it could fit into a few other enzymes, but not very well; I believe this is the major alternative pathway).

What happens is your body takes alcohol and begins to oxidize it. Ethanol turns into acetaldehyde, which turns into acetic acid, which your body knows how to handle fine. The ethanol to acetaldehyde step is catalyzed by the enzyme alcohol dehydrogenase and requires one NAD+ (nicotinamide adenine dinucleotide, an endogenous oxidizing agent involved in glycolysis. The acetaldehyde to acetate step also requires NAD+ and is catalyzed by aldehyde dehydrogenase.
Relative to Anglos, many Asians have a paucity of aldehyde dehydrogenase, causing acetaldehyde to build up when ethanol is consumed. This causes the flushed face seen in many Asians after even moderate alcohol consumption. In all populations, NAD+ is limiting; your body simply does not have that much. It is regenerated, but slowly, so even after moderate alcohol consumption, NADH (the metabolite of NAD+) to NAD+ regeneration is the limiting step in the alcohol to acetate cycle. This is poorly understood — understandably. Not many research dollars get routed to hangover prevention, since it’s essentially a nuisance and considered a “disease of excess.”
Read the rest of this entry »

GHB stands for gamma-hydroxybutyrate. It has received buckets of terrible press in recent years that would certainly have resulted in lawsuits in both directions if it was a patented pharmaceutical. Let’s take a look at the structure, then we will take a look at the days of yore when GHB was a blameless little molecule you bought at GNC (or you could get from Aldrich for organic synthesis). Then, we’ll take a look at the subsequent demonization and where we stand today.

Read the rest of this entry »

Friday, we talked about about carvone. I mentioned that it comes from the same biosynthetic pathway as cholesterol. The precursor to this, as well as a number of other natural products, is isopentenyl pyrophosphate, which we’ll refer to as IPP:

A few things this ends up in are compounds like carvone, limonene, and menthol, shown below:

Read the rest of this entry »