How powerful synthetic drugs will upend drug markets globally

[S.J.B.]

I disagree. If the precursors are not natural products, then the resulting compound will be synthetic regardless of synthetic route. If the precursor chemicals are natural products, the the resulting compound will be semi-synthetic.

For example, methamphetamine: acetylene-->benzene-->benzaldehyde-->PNP-->P2P-->meth (synthetic)
but
ephedrine-->methamphetamine (semi-synthetic)

The deciding factor is the original precursor. Acetylene is synthetic, while ephedrine is a natural product.

Yeah, by "synthetic routes" I was including the precursor used, sorry if I wasn't clear.