Pethidine intermediate A
Pethidine intermediate A is a four-phenylpiperidine derivative that is a precursor to the opioid analgesic drug pethidine (meperidine). It is not known to have any analgesic activity in its own right, however other derivatives of pethidine with a 4-cyano group in place of the carboxylate ethyl ester have been found to be active, so pethidine intermediate A might also show opioid effects.