Drug manufacturing isn't easy, most of the stuff is controlled and purchases of quantities of many required compounds will often immediately involve one or more

Drug manufacturing isn't easy, most of the stuff is controlled and purchases of quantities of many required compounds will often immediately involve one or more government agencies, generally the DEA. See: https://en.wikipedia.org/wiki/DEA_list_of_chemicals https://en.wikipedia.org/wiki/DEA_list_of_chemicals I see this a lot at work, I clear international freight through Customs (and any other applicable government agencies) for a living, and a lot of tariff numbers will flag as potential precursors by DEA.