▁of ▁natural ) ▁c oca ine ' s ▁mole cular ▁structure , ▁with ▁the ▁result ▁product ▁sufficiently ▁similar ▁to ▁c oca ine ▁to ▁display ▁similarity ▁in , ▁but ▁alter ation ▁to , ▁its ▁chemical ▁function . ▁Within ▁the ▁scope ▁of ▁analog ous ▁comp ounds ▁created ▁from ▁the ▁structure ▁of ▁c oca ine , ▁so ▁named ▁" c oca ine ▁analog ues " ▁retain ▁ 3 β - ben zo y lo xy ▁or ▁similar ▁functionality ▁( the ▁term ▁specifically ▁used ▁usually ▁distingu ishes ▁from ▁ph eny lt rop anes , ▁but ▁in ▁the ▁broad ▁sense ▁generally , ▁as ▁a ▁category , ▁includes ▁them ) ▁on ▁a ▁trop ane ▁ske leton , ▁as ▁compared ▁to ▁other ▁stim ul ants ▁of ▁the ▁kind . ▁Many ▁of ▁the ▁semi - syn th etic ▁c oca ine ▁analog ues ▁proper ▁which ▁have ▁been ▁made ▁& ▁studied ▁have ▁consisted ▁of ▁among ▁the ▁nine ▁following ▁classes ▁of ▁comp ounds : ▁ ▁s tere ois om ers ▁of ▁c oca ine ▁▁ 3 β - phen yl ▁ring ▁subst it uted ▁analog ues ▁▁ 2 β - subst it uted ▁analog ues ▁ ▁N - mod ified ▁analog ues ▁of ▁c oca ine ▁▁ 3 β - car b amo yl ▁analog ues ▁▁ 3 β - alk yl - 3 - ben zy l ▁trop anes ▁▁ 6 / 7 - subst it uted ▁c oc aines ▁▁ 6 - alk yl - 3 - ben zy l ▁trop anes ▁ ▁pi per id ine ▁hom olog ues ▁of