Molecule of the Day

Sorry if you’re sick of this, but I’m having fun. You might remember my post on Havidol. (see also this follow-up). Justine Cooper (presumably) left a comment on the initial post, plus the prescribing information (PDF) has been updated. It’s still not quite right – here, apparently, is your opportunity to make it right, and get a commemorative t-shirt in the process!

Previously, the entry for Havidol gave a name that didn’t match the structure. The same was true of the molecular formula and molecular weight:


After making a couple posts to this effect, I got this follow-up:

We at HAVIDOL are flattered that you have thought to include us in your blog.

A kind professor of chemistry had advised us of the errors of our ways a few days ago. We have endeavored to make some changes to the PI on the HAVIDOL site. But we are just a bunch of lazy artists over here so it has been quite difficult to implement these changes and we are quite sure we have probably bungled it anyway. Our original chemistry specialist was discredited when it turned out that he was acutally a veterinary pathologist and not a chemist at all!

We’d like to send a HAVIDOL T-shirt ($25 value) to anyone out there interested in concocting an authentic HAVIDOL Prescribing Information PDF. It’s only 25 pages long and at a $1/page that is more than any of us have been paid since we took on this god-forsaken job of constructive parody.

Bob C. had a point when he said that most people never notice anyway. So it is our privilege to be ‘exposed’ by molecule of the day. Certainly the ad people who came to the physical exhibition never noticed.

Thanks for making us feel special.

The HAVIDOL team.

The new entry uses this structure:


Unfortunately, changing the structure a little bit means that the nomenclature, molecular formula, and molecular weight of the old one don’t quite jibe. This one has the above nomenclature, molecular formula C18H10N2 and molecular weight 254.29.


If you want a hydrochloride salt (let’s please not argue over whether it would precipitate as the mono- or di-hydrochloride), you’ll have the above structure (the two nitrogens are degenerate, so this is unambiguous), nomenclature, and have molecular formula C18H11ClN2 and molecular weight 290.75.

Please let me know if you end up writing the monograph for this! I really would do it if I had the time. C’mon, she was a good sport…


  1. #1 Uncle Al
    March 1, 2007

    Natural product epibatidine is 200X more potent than morphine. An OTC consumer market spinoff is assured.

    Consider 2-chloronicotine re the 2-chloropyridine moiety of epibatidine. Expect increased potency from stronger binding to the hydrophobic areas of the nicotine receptor protein. Epibatidine’s N-N distance and conformation will be maintained and rigidly held.

    Begin with nicotine and its 1-chloro enhancement. Add a one carbon bridge between its pyridine and pyrrolidine rings to extend the N-N distance. Maintaining S-chirality of the pyrrolidine ring junction connect not to the 2-pyrrolidino position but to the 3-pyrrolidino position. With the N-N distance set, lock it. Cis to the 3-pyrrolidino ligation we add an oxygen at the 4-pyrrolidino site, and tie its other valence to the pyridine 4-position. Obtain a rigid, fused three-ring system reminiscent of serious tricyclic anti-depressants and anti-psychotic medications embellished with intense opiod activity.

    Feed it to bothersome children and their disintegrating mothers. Havidol – when life must be reordered to go.

  2. #2 Uncle Al
    March 1, 2007

    Epibatidine acts upon nicotine receptors not opioid receptors. A bigger N-N bite is the supposed reason for potency, re ABT-594. HyperChem gives quick and dirty N-N bites of 4.741 A for nictotine and 5.505 A for epibatidine.

    The small ZIP file above contains four Havidol candidates as HyperChem *.hin files and *.png graphics plus nicotine and epibatidine. Havidol-A has an N-N bite of 5.453 A. It’s a kludge but it is good enough for the purpose.

    (Side effects may include but may not be limited to satyriasis, fulminating bacteremia, icthyosis, intravascular disseminated coagulation, canthariasis, hematopoietic oncogenesis, and precipitous morbidity. Consult your physician if any of these conditions persist.)

    Organic chemistry is life; everything else is waiting. Hug a migrant pharm worker today.

  3. #3 Dirk
    March 1, 2007

    Uncle Al,

    Do you expect anyone to open a zip file from your site? It’s too dangerous to go around opening zip files.

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