\chemfig{
                    O% 2
           =[:149.3]% 12
                       (
                -[:89.3]% 13
                           (
                    -[:29.3]% 15
                   =_[:89.3]% 16
                    -[:29.3]% 18
                  =_[:329.3]% 20
                   -[:269.3]% 19
                  =_[:209.3]% 17
                   -[:149.3]% -> 15
                           )
               -[:149.3]% 14
            -[:89.3,,,1]OH% 3
                       )
           -[:209.3]O% 1
             -[:150]% 11
              -[:96]% 9
     -[:160.2,2.065]% 5
      -[:53.1,1.228]% 4
                       (
                -[:65.5]% 21
                       )
    =^[:257.9,2.285]% 6
                       (
          -[:315.8,1.22]% 10
                  -[:24]% -> 11
                       )
     -[:193.9,1.225]% 8
             -[:105]% 7
                       (
            -[:26,1.323]% -> 5
                       )
}