Substituted chroman derivatives, medicaments and use in therapy

1. A compound of formula (I-b):

wherein

R 1 is C 1-6 alkyl;

the drawing “ ” and R 2 together represent a double bond or

the drawing “ ” represents a single bond and R 2 is hydrogen or hydroxy;

R 3 , R 4 and R 5 are independently hydrogen, hydroxy, C 1-6 alkoxy or C 1-6 alkyl;

R 6 is hydrogen;

R 7 is C 1-6 alkoxy;

R 8 and R 9 are independently hydrogen, hydroxy, halo, C 1-6 alkoxy or C 1-6 alkyl;

or a pharmaceutically acceptable salt thereof.

2. The compound of claim 1 , wherein R 1 is methyl.

3. The compound of claim 1 , wherein the drawing “ ” represents a single bond and R 2 is hydrogen.

4. The compound of claim 1 , wherein R 3 is C 1-6 alkoxy or hydroxy.

5. The compound of claim 1 , wherein R 3 is C 1-6 alkoxy.

6. The compound of claim 1 , wherein R 6 is hydrogen.

7. The compound of claim 1 , wherein R 8 and R 9 are independently hydrogen, hydroxy, C 1-6 alkoxy or C 1-6 alkyl.

8. The compound of claim 1 , wherein:

R 1 is methyl;

R 3 is hydroxy or methoxy;

R 4 and R 5 are hydrogen;

R 7 is methoxy;

R 8 and R 9 are independently hydrogen, hydroxy, or methoxy;

or a pharmaceutically acceptable salt thereof.

9. The compound of claim 8 , wherein the compound has the structure:

10. A composition comprising one or more compounds of formula (I-b) of claim 1 , or a pharmaceutically acceptable salt thereof, in association with one or more pharmaceutical carriers, excipients, auxiliaries and/or diluents.

11. The composition of claim 10 , further comprising an anti-cancer agent.

12. The composition of claim 11 , wherein the anti-cancer agent is cisplatin, dehydroequol or paclitaxel.

13. The composition of claim 10 , wherein the compound of formula (I-b) is:

14. The composition of claim 13 , further comprising an anti-cancer agent.

15. The composition of claim 14 , wherein the anti-cancer agent is cisplatin, dehydroequol or paclitaxel.