The experiments were simple ones, of course. Each began with the same starting material, salicylic acid. Both reactions were esterifications, via different conditions.

The first experiment was an acetylation of the phenolic hydroxyl group of salicylic acid with acetic anhydride to give acetylsalicylic acid (aspirin) as its product. I had known for many years at that time what the chemical name for aspirin was — but I didn’t really have an understanding of what it meant. This changed that.

The second was a Fischer esterification (although I don’t recall referring to name reactions in high school) of the same salicylic acid starting material in methanol, to produce methyl salicylate, or oil of wintergreen. The smell of every reaction I would ever again run went downhill after that. (And, of course, you should not deliberately smell the contents of your reaction flask.)

It fascinated me at the time that the same starting material could give products with vastly different properties and uses via a single functional group conversion. To me, this is still one of the cooler parts of organic synthesis — made even cooler when you’re making and characterizing compounds yet unpublished in the scientific literature.

No, I don’t recall what yields I achieved running these reactions. For the sake of argument, we’ll just say it was quantitative. Or a “Swiss yield.” (Bad chemistry joke alert: A Swiss yield is when you leave in the stirbar when weighing your product. I think I first heard that one during a Rick Danheiser seminar. Chemistry humor — not an oxymoron. Believe it!)

Now that I’ve spilled…what aspect of chemistry, or any other science, had you “at hello?”

It gets better. That same day, I walked past one of our other cats, who was lazily sprawled across the kitchen floor. I reached down to pet his head, and there, between his paws was yet another mouse. This one was more intact, but equally dead. More importantly, it was in the kitchen. So, we’re on the lookout for more, and a bit wary. But, like I said, we have three cats – hopefully they’ll quickly address the problem for us.

What’s the chemistry connection? Well, these events brought back a memory of when I was a chemistry grad student. My wife and I were dating back then, and she and her roommate had a similar mouse problem in their apartment. Sadly, however, they had not one cat. What was their solution? First they tried traps – no luck. The little bugger evaded the jaws of death, and still roamed freely through their kitchen cabinets. It kept nibbling its way into boxes of food, and left its tiny mousepoop everywhere in a seemingly unending act of defiance. The stakes were high, and they decided the best strategy would be to poison their cute, yet disgusting, houseguest. Clearly, these two young women were not to be trifled with. (Did I learn a lesson there? You betcha.)

They purchased a couple of d-CON Mouse-Prufe Bait Wedges, and set them in strategic hidden places. (I should point out that back then, live traps were not readily available, so it wasn’t really an option to capture and possibly rehabilitate the mouse) A few days later, the effectiveness of this product became clearly evident as the smell of a dead and rapidly decaying mouse filled the apartment. I seem to remember it took a day or so for the two of them to finally locate the mouse, tucked away behind the bottom drawer of a kitchen cabinet. As neither of them wanted to touch the mouse-corpse, I was called over. I picked up the dead mouse with a newspaper and took it outside to dispose of it. I returned inside where accolades were showered upon me for the manliness of my achievement. Okay, maybe not so much.

The active ingredient that caused the mouse’s demise was warfarin, which works by interfering with normal blood coagulation processes. Basically, the poor critter died from massive internal bleeding. Nice, huh? I try not to think about it.

Sorry, warfarin is not named after Worf, Son of Mogh. But, hey, thank you for playing. photo courtesy CBS Studios Inc

The anticoagulant action, at a reduced level, can have a beneficial effect for people. Warfarin (commonly under the trade name Coumadin) is widely sold as a blood-thinning drug. Warfarin got its name from WARF (Wisconsin Alumni Research Foundation, which funded the initial key research) and the suffix –arin to reflect its coumarin substructure. Sadly, it is not named after Worf, from Star Trek: The Next Generation.

Coumarin is a fragrant heterocyclic organic compound present in several species of plants, such as sweetgrass, sweet clover and woodruff. Coumarin itself has little to no anticoagulant properties. These effects were first noted in the 1920s in cattle that were hemorrhaging after minor procedures such as dehorning or castration (minor procedure?!). It was traced to the cattle having eaten silage containing sweet clover which had become moldy. The fungus combines two relatively harmless coumarin molecules into a dimeric compound, dicoumarol, a powerful anticoagulant.

Warfarin, dicoumarol and other 4-hydroxycoumarins work by inhibiting an enzyme which recycles vitamin K, critical to the function of normal blood coagulation pathways. At low doses this is beneficial for patients at risk for heart attack, stroke or pulmonary embolism due to conditions such as deep vein thrombosis (DVT). It is also given to prevent the formation of blood clots in patients with prosthetic heart valves. Too much warfarin, and, well…you get the picture. As a colleague in safety assessment once said, “The dose makes the poison.” The dosage range from the lowest dose where a compound has the desired effect to the dose where unwanted (adverse) effects begin to outweigh the desired effect is often referred to as the margin or therapeutic window.

Currently, the use of warfarin to kill rodents has been largely replaced by more lethal 4-hydroxycoumarin derivatives, such as brodifacoum (3-[3-(4′-bromobiphenyl-4-yl)-1,2,3,4-tetrahydro-1-naphtyl]-4-hydroxycoumarin). The increased lethality of the newer rodenticides is because, in part, they tend to accumulate in the animal, where warfarin is fairly rapidly excreted. The need for newer, better toxins is also because many populations of rats and mice are now warfarin-resistant. (Evolution at work again!) The downside of the structural modification to offset rapid excretion is that these toxic compounds can then bioaccumulate throughout the food chain, as scavengers and predators feed on the rodents. Not a good thing.

While our mouse problem is an issue and we’re not happy about it, we’re not going to turn to poisons or traps. We’re going to try to reduce the attractiveness of our garage to the mice as much as we can. Failing that, we’ll rely on our cute but ruthless predators. We should probably start sleeping with one eye open.

Due to contest rules, the world will just have to wait for my seminal essay on Yttrium -- all in iambic pentameter. Photo courtesy of Wikipedia user Alchemist-hp

Sadly, I cannot enter the competition, as I don’t quite fit the demographic. The instructions stipulate that it shall not be more than five years since the final training appointment (e.g., Ph.D. or postdoctoral position) of any competing author. Also, the essay must cover one of seven elements: helium, nitrogen, sodium, copper, bromine, indium or plutonium. If you have a burning desire to write about any of these elements, now’s your chance!

I can think of one specific example where a former neighbor, an electrician, gave me advice on how to drill a hole through my foundation, dig a trench, and run some cable out to our backyard pond to hook up a receptacle to power the pond pump. I followed his suggestions (all up to code, of course), and it still works great to this day. See? Neighbor = useful resource.

Yes, those are lab coats. Dont be afraid...

But, a chemist? Heck, the minute you tell your neighbor you’re a chemist, there’s usually an awkward pause, and if they follow up with anything at all, it’s “So, um, what do you do?” So you assess the expertise level of your audience and begin to explain what you do, the goal of your research, and how it possibly might fit in to something that could affect them at some point.

Three or four sentences in, however, it’s clear that they didn’t really want an explanation at all, on any level. Their eyes glaze over a bit, then they avoid eye contact and perhaps fidget. If you’re quick enough to pick up on these social cues, you can try to recover with something like, “Hey, how about that local sports team?”

No chemistry experiments happening here, folks. Please move along.

Being a chemist means being met with suspicion. What am I up to, you ask? Do you suspect, say, that I’m doing experiments? Trust me, pal, without a fume hood, I’m not synthesizing anything, legal or otherwise, that involves the use of organic solvents. The catboxes smell bad enough.

And as far as being asked for my help with something, I’m not holding my breath (with or without a hood). I can’t recall one instance where a neighbor has come over and said, “Hey, you’re a chemist. Do you have a minute? I need some help with…this…um…thing.”

So, to all my past and current neighbors…I’m sorry. I apologize that my chosen field is one not ideally suited for home use. Please forgive me for my seeming inability to share your alarm in discovering that a food product you love contains chemicals. I am truly sorry.

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• In Defence of Chemists (Philosophically Disturbed)

1. Submitting pure target compound to an assay for testing
2. Purifying crude material by trituration and avoiding a tedious chromatography
3. Finding an inexpensive, reliable vendor for a critical intermediate as an alternative to Aldrich
4. That moment when a crystallization begins to bloom
5. Elucidating the structure of an impurity that gives you insight to optimizing reaction conditions
6. Using a synthetic step from the literature that’s really old (i.e., older than me)
7. When pure product crashes out of a reaction mixture
8. Spot-to-spot conversion by TLC
9. When a colleague is excited about an experimental result
10. That “A-ha” moment in data analysis
11. Tension-free project meetings
12. Learning early on that being serious about science wasn’t the same as being solemn