Synthesis of a phthaloylglycine-derived strigol analogue and its germination stimulatory activity toward seeds of the parasitic weeds Striga hermonthica and Orobanche crenata

The newly designed strigol analogue Nijmegen 1 (rac 7) was prepared in high overall yield starting from N-phthaloylglycine, This relatively simple analogue exhibits high bioactivity in the stimulation of germination of seeds of the parasitic weeds Striga hermonthica and Orobanche crenata. Nijmegen 1 was resolved in its enantiomers 7 and ent 7 by using the homochiral latent D-rings ent 11 and ent 12. The enantiomers 7 and ent 7 show significant differences in germination activity.