Stock Photo Science - Colchicine

Our tiny company doesn't have a true marketing or business development staff, so publicity often falls to the scientists - y'know, during our "down time." : )

For the past month, I've been trawling stock photo sites and "how-to" guides to assemble some company brochures for an upcoming event. Yesterday, I dug up this stock photo gem:

Source: iStockphoto
Now, Just Like Cooking 1.0 might have beleaguered the graphic artist, decrying his lack of experience and shouting about why we need more chemists in design departments. 

But I'm tryin', Ringo. I'm tryin' real hard to be the shepherd. Let's go piece by piece and try to figure out why we can't print this on our marketing materials.

For starters: the molecule I think they're looking for, colchicine, isn't exactly unknown. Doctors and healers have prescribed this plant extract for centuries to treat gout and local inflammation, despite concerns over its toxicity. Chemists have known how to make colchicine since at least the mid-1950s. 


So, here's how the molecule should look. There's some important differences here, perhaps most importantly that the acetamide (the "top" functional group, CH3-C=O-NH) should actually have a bond to the central ring. 

Next, let's move to the bottom right ring, which I'd call a cycloheptatrienone ("hepta" = 7, "trien" = 3 double bonds, "one" = ketone functional group). See how the double bonds are shuffled around in the stock photo? That would be OK, since the system does have other resonance structures, forms where just the electrons move around without breaking the carbon framework. But this structure, where the C=O and C=C bonds overlap, makes 5 bonds at that carbon. That only happens under very specific conditions, but certainly not in this drug.

Finally, check out those bonds on the left. We organic chemists use bond notation to infer a lot of crucial details, not least which atoms connect to which other atoms! Note the line drawn from the 6-membered ring to the "C" of the bottom methoxy (H3CO-) group. Perhaps an artistic choice, centering the group over the bond, but the real molecule shows a C-O bond. 

I know photographers don't often consult chemists before they take these shots, but I'd invite their input here. Wouldn't their business do better if their photos were accurate? 

Speaking as a scientist-cum-designer, it would make my job easier.

Happy Friday, everyone.
-SAO

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