propanamide or any analogue of N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl] propanamide, and if death or serious bodily injury results from the use of such substance, such person shall be sentenced to life imprisonment or death. (9) In the case of a violation of subsection (a) involving a mixture or substance in an amount of 100 grams or more, if the mixture or substance containing a detectable amount of N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl] propanamide or any analogue of N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl] propanamide was represented to be or sold as heroin, and if death or serious bodily injury results from the use of such substance, such person shall be sentenced to life imprisonment or death. .