http://acsh.org/news/2016/06/16/chemists-were-wrong-about-splenda/
Medicinal chemists — organic chemists who study drugs — frequently develop an ability that is sometimes informally called “eyeball toxicology,” or the ability to determine a rough idea of the toxicity of a substance just by seeing its chemical structure on paper. It is a form of intuition. The longer you do the job, the better you get at it.
It would be reasonable to call this skill a “highly educated guess,” which is acquired through years of studying the relationship between the structures of a variety of chemicals and their toxicity. It’s not perfect, but we often get it right. It could just as easily called acquired toxicological judgement. Or, “that is one nasty looking molecule!”
But, it failed miserably with the artificial sweetener Splenda (sucralose). To many medicinal chemists, sucralose looked like bad news, but turned out to be just the opposite. More on that later.
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