Thank you Sir Chesebrough

I have a lot of favourite chemicals, including caffeine and paracetamol. Lately, though, my favourite chemical has become soft paraffin. Soft paraffin (petroleum jelly or petrolatum) is a non-polar, hydrophobic hydrocarbon mixture. It is not one chemical structure but a mixture of hydrocarbon chains (around 25 carbons in length) with a melting point similar to that of the human body’s temperature.



I suffer from excruciatingly itchy legs, mostly in the winter months. It keeps me (and my poor other half) awake at night. I can even draw blood without realising. Various creams keep my itching at bay but what most of these creams/lotions/balms have in common is that they contain soft paraffin. This works by forming a layer that prevents loss of moisture from my skin and also protects my skin from harsh conditions.

This stuff saves me from having sleepless nights and scarred legs, so thank you Sir Chesebrough for devising the process of extracting these chemicals from oil (U.S. Patent 127,568) and believing wholeheartedly in your product.

Are there any chemists you wish to thank for an amazing or useful discovery? If so, who and why?

Taking Medicines

Is it just me, or do all chemists guess the structure of a medicine before they take it? After having a guess, I then Google it and look up the synthesis, where possible.

I am currently using Ketoconazole for a skin condition (over-share, sorry). Immediately I knew there was a ketone (keto) and a nitrogen containing heterocycle (azole = five-membered nitrogen ring containing at least one other heteroatom) in there.  Conazoles are a common type of fungicide containing an imidazole or triazole ring so that narrowed it down further for me. I could not predict any thing more so looked up the structure (DOI: 10.1021/jm00194a023). It is actually a lot more complex than I expected.



Similarly, a few years ago I took Metronidazole and, as usual, I tried to predict the structure from the name. I guessed there was a nitrogen heterocycle, probably an imidazole ring and possibly nitro group. I wasn’t far off this time! When looking up the structure, I was very surprised by the simplicity of the structure and the synthesis (DOI:10.1007/BF00764821).

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So, is it just me? Or do you all try and predict aspects of a drug molecule before you take it? Have you ever guessed close to the true structure? If so, share in the comments section below.