[oollusia]

I search for information about prothioconazole and tebuconazole. Do you know what is the activity difference between enantiomers? Why are they manufactured as a racemic mixtures?

[orgopete]

I don't know these fungicides, but for the sake of argumen, let us assume one isomer is active and the other completely inactive. If the cost to prepare the single isomer is greater than the cost of the inactive isomer, then the cost to the farmer would simply be cheaper for the racemic mixture.

In a project I worked on, we prepared a single isomer of an intermediate that was later coupled with a much more expensive fragment in an effort to exact a cost savings at that point. It turned out to be experimentally feasible, but not as a production or commercial scale. So, it depends…