system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Can chemists follow formula like a recipe?

For example, Salt has the chemical formula NaCl, so if you bond sodium with chloride, you will get salt.

Could a chemist apply this same principle to say Insulin (C257H383N65O77S6). Using the chemical formula alone to replicate the substance in question?

If this is the case, why are knock-off drugs not more common, couldn't a rival lab (or illegal labs) just take the publicly available formula and replicate it at a fraction of the c0st?
gpt
No. That’s not how chemistry works.

Saying that c^(6)H^(12)O^(6) is sugar is kind of like say a particular LEGO model is 6 red bricks, 12 blue bricks, and 6 yellow bricks. There is not enough information to build the model even though you know the ratios.