A few weeks back there was a lot of discussion over the bad bosutinib which had come from the wrong aniline being used in its synthesis – fortunately none in the clinical trials, but making a mess of the other research work being done using it.
I will guess that most folks working in a lab have had some sort of “bad bosutinib” story, though obviously not quite so important and more easily caught. Many wise heads shake when a bright young chemist offers up his bought LDA solution – better make it yourself, I was always told. I’ve had another couple of stories recently that I will share today.
The first was a bought chemical – ethyl bromoisovalerate. I was interested in that isopropyl group being added to my molecule and ran my chemistry as usual. But when I got my NMR of my product, the distinctive isopropyl was nowhere to be found. Turned out to be ethyl bromovalerate – the straight chain version. A shame, as I had already bought that one.
This one was easily caught because I knew what I was looking for. The other was not so easy for me for the exact opposite reason – I did not know what was wrong.
This one was some HPLC vials. I had used screw cap ones all my career to date, but my colleague that was in charge of the HPLC (and whose stock of vials I was raiding) used push on caps. Well, no problem, except they wouldn’t stay on. Not just one or two either, but half the vials had the caps slowly rising up off the vial again – a major concern when you are doing automatic injections. The needle will not like that. I complained to my colleague about the caps and how terrible they were and she told me that she’d never had a problem with them before. Then we really looked at them – they weren’t quite right. There was no little groove on the vial lip for the cap to clip onto (see my poorly taken photo).
As soon as I changed the vials for a fresh box that weren’t all faulty, the problem went away. I didn’t realize straight away because I wasn’t familiar with these kinds of caps and how they worked. Sometimes you just have to say to yourself “they wouldn’t deliberately make them so difficult to use.”