The structural formula of cocaine is;
CH3
/
O
\
C=O
/
CH2--CH--CH
/ / \
CH2 N-CH3 CH-O
\ / / \
CH2 ------CH2 C=O
/
Ph
Ph represents
phenyl group
It is possible to synthesise cocaine by a variety of routes, but all of these are either very difficult if they start without the tropinone ring, or use precursors that are unobtainable, expensive, or dangerous (eg. atropine)