Substituted chroman derivatives, medicaments and use in therapy

1 . A composition comprising a compound of formula (I-b): 
       
         
           
           
               
               
           
         
         or a pharmaceutically acceptable salt thereof wherein: 
         R 1  is hydroxy, halo, C 1-6  alkoxy or 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, halo, NR 10 R 11 , C 1-6  alkoxy, C 1-6  fluoroalkyl or C 1-6  alkyl; 
         R 6  is hydrogen, hydroxy, halo, C 1-6  alkoxy or C 1-6  alkyl; 
         R 7  is hydroxy or C 1-6  alkoxy; 
         R 8  and R 9  are independently hydrogen, hydroxy, halo, NR 10 R 11 , C 1-6  alkoxy, C 1-6  fluoroalkyl or C 1-6  alkyl; and 
         R 10  and R 11  are independently hydrogen, C 1-6  alkyl or trialkyl silyl; 
       
       and an anti-cancer agent, 
       wherein said composition is optionally in association with one or more pharmaceutical carriers, excipients, auxiliaries and/or diluents. 
     
     
         2 . The composition of  claim 1 , wherein the anti-cancer agent is cisplatin, dehydroequol or paclitaxel. 
     
     
         3 . The composition of  claim 1 , wherein the compound of formula (I-b) is selected from compound Nos. 1 to 9 and 42 as set forth below: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         4 . The composition of  claim 2 , wherein the compound of formula (I-b) is: 
       
         
           
           
               
               
           
         
       
     
     
         5 . The composition of  claim 3 , wherein the anti-cancer agent is dehydroequol. 
     
     
         6 . The composition of  claim 4 , wherein the anti-cancer agent is dehydroequol. 
     
     
         7 . A method for the treatment, prevention or amelioration of cancer or a tumour mass, which comprises administering to a subject in need thereof a therapeutically effective amount of a compound of formula (I-b) as defined in  claim 1 . 
     
     
         8 . The method of  claim 7 , wherein the compound of formula (I-b) is selected from compound Nos. 1 to 9 and 42. 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         9 . The method of  claim 7 , wherein the cancer or tumour mass is of epithelial origin, of mesenchymal origin or of neural origin. 
     
     
         10 . The method of  claim 9 , wherein the cancer or tumour mass of epithelial origin is prostate, ovarian, cervical, breast, gall-bladder, pancreatic, colorectal, renal or non-small lung cancer. 
     
     
         11 . The method of  claim 9 , wherein the cancer or tumour mass of mesenchymal origin is melanoma, mesothelioma or sarcoma cancer. 
     
     
         12 . The method of  claim 9 , wherein the cancer or tumour mass of neural origin is glioma. 
     
     
         13 . The method of  claim 7 , wherein the compound is simultaneously administered with an anti-cancer agent. 
     
     
         14 . The method of  claim 7 , wherein the compound is sequentially administered with an anti-cancer agent. 
     
     
         15 . The method of  claim 13 , wherein the anti-cancer agent is cisplatin, dehydroequol or paclitaxel. 
     
     
         16 . The method of  claim 14 , wherein the anti-cancer agent is cisplatin, dehydroequol or paclitaxel. 
     
     
         17 . The method of  claim 13 , wherein the compound of formula (I-b) is: 
       
         
           
           
               
               
           
         
       
       said anti-cancer agent is dehydroequol, and said subject is afflicted with ovarian or pancreatic cancer. 
     
     
         18 . The method of  claim 14 , wherein the compound of formula (I-b) is: 
       
         
           
           
               
               
           
         
       
       said anti-cancer agent is dehydroequol, and said subject is afflicted with ovarian or pancreatic cancer. 
     
     
         19 . The method of  claim 7 , wherein the compound acts as a radiosensitising agent. 
     
     
         20 . The method of  claim 7 , wherein the compound acts as a chemosensitising agent.