PMK is Piperonylmethylketone.
Although I'm not sure about this it appears contrary to what I thought previously you need some safrass to make it. I'm not at all convinced with this article as there are a few things to me that do not add up whatsoever and I am now out of my depth with this you need someone with some sort of chemistry knowlage, but.......
http://www.mdma.net/club-drugs/global-ecstasy.html it's a bit of a read but skim through it there is some intresting stuff at the start and the end. Also explains that bust I was on about in 06 that contributed to the drought.
To be honest I wouldn't take anything from that article as gospel at all. MDMA can be synth'd from straight sassafras oil, so why would they need to make it into PMK? Unless it rations out the sassafras oil a bit further? I'd always thought PMK was completely inorganic.
If this is all true it makes a bit of a joke of the sassafras MDMA vs PMK MDMA (not that it wasn't already a joke as MDMA is MDMA).