Amphetamine, C9H13N, is a synthetic central stimulant. The name derives from its chemical designation: alpha-methylphenethylamine. As amphetamine in its pure form is liquid[1] it is usually converted to amphetamine sulfate which has a solid form and is easier to handle as a powder. Amphetamine and various derivatives are used in medicine, but mainly as an illegally used drug.

https://en.wikipedia.org/wiki/Amphetamine