Howard Florey (along with Alexander Fleming and Winston Churchill's government) spend ten years before during and after WWII pursuing the chimera of totally artificial (patentable) penicillin --- to no avail.
As did Florey's supporters in America - Merck, Squibb and Vannevar Bush's all-powerful OSRD.
Set against then, on the opposite side of the Hudson River , was Dr Martin Henry Dawson and John l Smith , chemist and boss of Pfizer.
They saw possibilities in the fermentation of the (public domain - free for all to grow) natural penicillium to produce antibiotics.
This was despite its current yields being admittedly low: they felt as it was a totally new way of doing medicine , it might well improve drastically with more practise.
(I should mention that two other strong skeptics of the whole idea of the commercial viability of total synthesis of penicillin were also practising chemists : Glaxo boss Harry Jepcott and the WPB's penicillin czar Larry Elder.
It was chemist manques like Florey and the OSRD's Dr Richards who were the most likely to feel that of course man-made Chemistry was always bound to be superior to Mother Nature.)
Today of course, with penicillin being produced at 50,000 times the levels of Fleming for the same cost in time labour and materials, the case against oxford Artificial seems clear - but it wasn't so throughout the war and beyond.
Long Island scientist Miloslav Demerec deserves a lot more credit than he ever gets (which is none !) for his major role in making our wonderful world of relatively cheap abundant antibiotics ....