4-APB is a positional isomer of the designer drug 6-APB , also known as benzo fury, found in recreational drugs. It is expected to have psychoactive effects similar to 6-APB. 4-APB is also an analog of MDA in which the 3,4-methylenedioxyphenyl ring system has been replaced with a benzofuran ring. This product is intended for forensic and research applications.