To Mr Sternbach, tinkering with someone else's drug was a dull sort of job.

ECONOMIST: Leo Sternbach

Mr Sternbach's job was to find a compound just as good, or better, with just enough differences to get round Wallace's patent.

ECONOMIST: Leo Sternbach

"The pharmaceutical industry had the courage to come out with compounds very quickly, " Sternbach told Forbes in 2003, two years before he passed away.

FORBES

The late Roche scientist Leo Sternbach invented Valium, Klonopin (No. 6) and several other similar drugs in the heady days of the early 1960s.

FORBES

Under pretence of finding it accidentally, and being about to throw it away, Mr Sternbach took his powder to the head of pharmacology for testing.

ECONOMIST: Leo Sternbach

Leo Sternbach, in 1954, was ordered to find such a medicine.

ECONOMIST: Leo Sternbach

In 1956 Mr Sternbach, fiddling with yet another benzodiazepine, treated it with methylamine, made a white crystalline powder, labelled it Ro 5-0690 and put it away on a shelf.

ECONOMIST: Leo Sternbach

VelaPharm Chief Executive Kevin L. Keim remembers seeing the tofisapam molecule, which was approved as a niche anxiety drug in 15 countries but never became a big seller, when he worked at Roche, alongside Valium inventor Leo Sternbach.

FORBES: Drug Industry Discovers Recycling

When I think of how much easier it was to invent new medicines a few decades ago, I usually mention the story of Roche chemist Leo Sternbach, who invented not only Valium but related drugs such as Klonopin and Librium.

FORBES: Valium, LSD, And Drug Discovery