Start with a benzene ring numbered so C1 carries the main side chain.

Let me describe the ring substituents:
1. C1: bears a methylene-secondary amine linkage, -CH2-NH-. The nitrogen is bonded to a tertiary carbon (C*), and C* carries two alkyl groups: an ethyl (-CH2-CH3) and an n-pentyl (-CH2-CH2-CH2-CH2-CH3).
2. Carbon-3 (meta to carbon-1): a methoxy group, -OCH3.
3. Carbon-4 (para to carbon-1): another methoxy group, -OCH3.