TASK DEFINITION: In this task, you are given a sentence. You are expected to recognize the name of any form of chemical substances. Although there might be several correct answers, you need to write one of them.
PROBLEM: Transdermal selegiline for the treatment of major depressive disorder.

SOLUTION: selegiline

PROBLEM: Adapalene, a new chemical entity with retinoid activity.

SOLUTION: retinoid

PROBLEM: Synthesis of C17-OH-north unit of ritterazine G via "Red-Ox" modifications of hecogenin acetate.

SOLUTION:
ritterazine G