“…In addition, 2-quinolones are embedded as core structures in natural products [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ]. While a number of naturally occurring derivatives have been released, early reports revealed hybrid compounds that are derived from an isoprene unit and quinolones, namely hemiterpenoids [ 35 , 38 , 39 , 40 , 41 , 42 , 43 ].…”