Analogues are drugs that have close structural resemblance and similar effects. For instance one could argue that naproxen (Aleve) is an analog of ibuprofen (Motrin/Advil). Most analogues are designed because true synthetic natural products are hard to make, or are not potent enough.
Definition of several. 1a : separate or distinct from one another federal union of the several statesb (1) : individually owned or controlled : exclusive a several fishery â compare common (2) : of or relating separately to each individual involved a several judgmentc : being separate and distinctive : respective specialists in their several fields.
It usually means 2, but can sometimes mean 2 or 3. The reason it's so hard to figure out is that different people will use it differently. Because it's just a colloquialism, there are no hard-and-fast rules for its use. I have most often heard it used to mean 2.. few of something means more than two, but still a small number. Several means more than two or three, according to WordWeb, and usually means more than a few.