Thank you bezo!
The tracer might actually be a solution but there's one thing I can't solve, maybe you could help me. My example might not have been the best because for some strings there are let's say 4 molecules in a row (A-B-C-D) but then there's also 1 molecule connected to B. This kind of thing was fairly easy to do with xpresso, connecting them this way but as soon as i try to randomize some movement the clones are no longer connected to the spline points.
If you or someone else have time, please have a look at this file to better see my problem.
molecule_xpresso_v2.c4d