Well, for chemistry, it's much easier for us: there are no rules, unless you want to make custom drugs (Chrome Flesh, p190). But for the drugs you want to make, nothing.
I suppose you could use the rules for Building & Repairing (with the modifiers p146, CRB) but it's not really made for this. And absolutely nothing is said regarding base materials you'd need, to compute costs, margins, etc. So it's pretty much up to the GM. It would be more important if we wanted to roll dice for every single thing, or if we wanted to know how much you make, but since we don't... It's a nice justification of the fact that we earn 2000 nuyens per 2 IC posts, so...
As for your storyline, I read it as all the other ones, and there's a link with Eva and Rose through Sian. Not a big one yet, but both of them know Sian.