There are lots of analogs of LSD and typically they're made by tweaking three different positions on the LSD molecule. 1) the nitrogen on the five-membered ring, 2) the nitrogen in the six-membered ring and the ethyl groups on the amide nitrogen. This patent doesn't stray from this formula (as I saw from skimming the structures) but the specific modifications they make are interesting, like putting in alkynes or oxetanes. They also have some pharmacology data on receptor binding but I can't speak much to that.