pentazocine

A benzomorphan is any of a class of analgesics, such as phenazocine and pentazocine, with a structure based on benzazocines.

Yes talwin is indeed a narcotic opioid pain killer. See Pentazocine

Talwin (pentazocine) is a synthetic opiate that is used to treat moderate to severe pain. Formerly a popular drug of abuse, it has largely been eclipsed by oxycodone.

Yes, Tylenol #3 (acetaminophen and codeine) may be taken tohether with penicillin, an antibiotic.