1. Core skeleton: a chromane ring system (a six-membered oxygen heterocycle fused to a benzene ring). Number the chroman as follows, starting in the heterocycle and proceeding around the fused system: an oxygen atom (position 1), a methylene (-CH2-, position 2), a benzylic methine (-CH-, position 3), and another methylene (-CH2-, position 4); position 4a is a fusion carbon with benzene ring; Positions 5, 6, 7, and 8 are benzene carbons; position 8a is another fusion carbon; finally back to the oxygen at position 1.

2. Substituents on the chroman system  
   a. Benzene ring: place one hydroxyl group on carbon at position 7.
   b. Heterocycle: the benzylic carbon at position 3 carries a phenyl substituent.

3. Substituents on the benzylic phenyl ring:  
   Relative to the point of attachment (taken as position 1 of this ring), install hydroxyl groups at the ortho (position 2) and para (position 4) positions; the ring is otherwise unsubstituted.  Thus the side ring is 2,4-dihydroxyphenyl.

4. No configuration is specified at C-3 of the chroman (stereochemistry at this center is undefined).