A Tale by Mail

Long-time readers will no doubt be aware of my running affectation with the "Profiles, Pathways, and Dreams" series of books from ACS; books which, had I not read them in grad school, would probably cause this blog to never exist.

So I have a sneaky hobby: scouring the Internet's used book counter to assemble an entire set. Thus far, I've collected 17 of the 22 from the original 1990-1995 run. As I'm simultaneously trying for thrift, I'm proud to say the most I've paid for one of these books was around $25.

One of the best came in the mail only today - a first-edition, basically mint copy of Djerassi's Steroids Made it Possible. You know, the one with the picture of Nobelist R.B. Woodward going Mike Tyson's Punch-Out! on another esteemed chemist?

Steroids Made it Possible, ACS Books, p. 60

I open the plastic packaging, breathe in the old-book-paper smell.  But wait, there's no library markings. And the book is, what, 26 years old, and is basically undamaged? Curiously, I opened the cover, and realized that Djerassi himself had dedicated it:

To whom, exactly? Why, to Larry Lehmkuhl, the previous president of St. Jude Medical, according to Bloomberg. And is that really Carl's signature? I've compared it against two *for sale* on eBay and at Amazon - $89 euro and $39.85, as of this writing, respectively - it's the real McCoy.

This, of course, raises more questions: Did Lehmkuhl ever read his gift? Was he from a chemistry background? (I can't find much about him through the usual channels).

Did Djerassi mail out copies of his books, en masse, to anyone interested? If so, perhaps other signed treasures are out there, waiting to be found.

ETC: Vonnegut, Djerassi, and a Mystery Polymer

I've recently finished the 1973 novel Breakfast of Champions, by acclaimed science fiction / humor writer Kurt Vonnegut. For those unfamiliar with Vonnegut's work, I enjoy drawing parallels* between him and "chemical provocateur" Carl Djerassi.

These two men share some odd similarities: born within 13 months of one another, each man suffered the Second World War - Djerassi as a refugee; Vonnegut as a POW - and had their personal lives scarred by young, tragic deaths in their families. Nevertheless, both became prolific writers of short stories, novels, and plays, and both lived to be elder statesmen in their chosen careers: Vonnegut to 85, and Djerassi to 91.

I'd even wager that they looked somewhat alike, with their bushy mustaches, well-coiffed hair, stylish clothing and impish eyes:

Novelist Kurt Vonnegut
Credit: Enotes

Chemist and writer Carl Djerassi
Credit: DLD / Stanford

Breakfast of Champions convinced me that Vonnegut may have had more than a passing fancy for chemistry, himself. Consider this hand-drawn rendering of a mystery plastic, ostensibly factory run-off that main character Kilgore Trout has unfortunately found stuck to his feet after wading through a river in Midland City, Michigan:

Credit: Kurt Vonnegut, Breakfast of Champions

Clearly, that's a cyanoacrylate co-polymer - think Superglue - and it seems to be drawn with a dendrimeric A-B-A architecture. I'm guessing that the ethylene glycol spacers (O-CH2-CH2-O) are meant to suggest the foaminess several characters encounter in the novel, that this mystery polymer is "...the stuff f***ing up Sacred Miracle Cave...", an in-book tourist trap overrun by large, odorous brown bubbles.

Incidentally, I love Vonnegut's inference for the continued polymer chain; where we chemists might write n, Vonnegut inserts his time-work "ETC."

Why? I'll let the author explain his philosophy:

"The man who taught me how to diagram a segment of a molecule of plastic was Professor Walter H. Stockmayer of Dartmouth College. He is a distinguished physical chemist, and an amusing and useful friend of mine. I did not make him up. I would like to be Professor Walter H. Stockmayer. He is a brilliant pianist. He skis like a dream.

 And when he sketched a plausible molecule, he indicated points where it would go on and on just as I have indicated them - with an abbreviation that means sameness without end.

 The proper ending for and story about people it seems to me, since life is now a polymer in which the Earth is wrapped so tightly, should be that same abbreviation . . .it is in order to acknowledge the continuity of that polymer that I begin so many sentences with 'And' and 'So,' and end so many paragraphs with '...and so on.' 

And so on. 'It's all like an ocean!' cried Dostoevski. I say it's all like cellophane."

Sometimes you encounter (surprisingly accurate) chemistry in places you didn't expect.
So it goes.

--
*Bonus: Here's Roald Hoffman interviewing both authors in a 1999 piece for American Scientist magazine

Satori Makes Good (Steroids)

Whether it's because of the evergreen interest in Carl Djerassi, the discovery of a (new-to-me!) blog, or Percy Julian's recent Google Doodle, everything in the blogosphere seems to be coming up steroids.

Take a peek at these back-to-back OPRD articles, both from chemists at the former Satori Pharmaceuticals.

As a "cub blogger" for CENtral Science, I still remember gaping at how radically different their root-derived phytosterols were from the rest of the anti-Alzheimer's medicines. Now, almost a year to the day after Satori shut its doors, we have some insight from the team responsible, just before they scattered to the winds.*

So, that means 6.99 tons of plant waste to dispose? [rubs eyes]
OPRD, 2014 ASAP

To access their preclinical candidate, Satori scientists first needed a reliable supply of the glycosylated intermediate. Enter seven metric tons of dried black cohosh, a traditional medicine used as a pain reliever by Native American healers. A third-party vendor crushed the root and sent it to another firm, where they extracted it with ethanol, passing about 300 kg of "solids" back to Satori. Suspension in brine / DCM partitioned the desired compounds into the organic phase, which was treated with triethylamine and catalytic zirconium tetrachloride. This ejects the pesky E-ring alcohol, and the resulting compound performs a net oxidation to yield a diastereomeric mixture of ketones (above).


(Warning: I guess you haven't lived 'til you've purified 70 kg of crude, brown extract with DCM over silica...yuck!)

So, once Satori had in hand ~11 kg of compounds 1 + 2 (see right), they needed to advance the structures to their desired candidate (below) which you'll notice has a few little changes from the plant-derived drug. Gone are the acetyl group. Reduced is the ketone. Ripped apart is the sugar, making way for a morpholine.

The scientists' first-gen synthesis, an 8-step sequence, wasn't up to snuff for kilogram work. The trouble? Too many chemically similar hydroxyls, prompting some protecting group manipulation to target one or two selectively. Process work on the ethyl ether step - utilizing diethylsulfate / tert-butoxide in place of an earlier NaH / EtI mix - allowed a telescoped 5 step route, cutting out 2 silica gel columns and upgrading the final process purity to >95%.

Interestingly, the authors, ever circumspect, reflected on the limitations of their final process:

"While this reported route was sufficient to provide the kg-scale quantities of target compound for preclinical studies, we acknowledge that it has limitations that would make it impractical at the 100 kg scale."

Silica gel chromatography strikes again! Still, their candidate came through on 1 kilo, at about 30% overall yield after HCl salt formation. Not too shabby.

Update (5/30/14): Want to see how Satori chose these molecules? One of the authors (Hubbs) writes in to recommend their 2012 J. Med. Chem. optimization paper.

*According to the author lists, everyone on the team ended up in a different place: Enanta, AstraZeneca, Celgene, ETH, Genzyme, Resilientx, Sanofi.

The Lion in Winter

Source: ACIEE | Karen Ostertag

Carl Djerassi + Jeffrey Seeman + Angewandte Chemie
= Must-read material.

Just when you thought you couldn't get enough of Carl's 90th birthday festivities, a new collection of personal quotes has appeared online this week. Djerassi - chemist / author / poet / provocateur - does not disappoint. For the more chemically-inclined, it's full of "Didja know?" moments - for instance, Woodward, Djerassi, and Tishler all submitted syntheses of cortisone to JACS within 3 weeks of each other!

The bulk of the text explores Djerassi's feisty, garrulous backlog of quotables. Here's just a sampling:

On his stamp: "Since 2005, people in Austria - by now thousands - have been licking the back of my head"

On publication: "You owe it to the students and those who collaborate with you...you persuaded them to do it, and obviously at the time that it was worth doing. Presumably, if they completed it, it was good enough to be published."

On community: "Scientists operate within a tribal culture whose rules, mores and quirks generally not communicated through specific lectures and books, but rather are acquired through a form of intellectual osmosis in a mentor-disciple relationship"

The rest run the gamut from social movements (performance-enhancing drugs, the Pill, sex, schadenfreude) to deeply personal hurts (professional exclusion, his daughter's suicide), and end on a peaceful, affirming story concerning the motto of the Djerassi ranch (SMIP, but I won't spoil the secret...)

Give it a read, it's worth every minute.