The first orally active semisynthetic steroidal estrogen, EE (17α-ethynylestradiol), the 17α-ethynyl analog of E2, was synthesized in 1938 by Hans Herloff Inhoffen and Walter Hohlweg at Schering AG in Berlin.
Oxamniquine is a semisynthetic tetrahydroquinoline and possibly acts by DNA binding, resulting in contraction and paralysis of the worms and eventual detachment from terminal venules in the mesentry, and death.