Hybrid-type strigolactone analogues derived from auxins

Area of Science:

• Agrochemical Science
• Organic Chemistry
• Plant Biology

Background:

• Strigolactones (SLs) possess diverse biological activities with significant ecological implications.
• Limited natural availability of SLs necessitates synthetic approaches for broader application.
• Structural complexity of natural SLs hinders cost-effective, large-scale synthesis.

Purpose of the Study:

• To synthesize novel, simplified strigolactone analogues with retained bioactivity.
• To develop cost-effective alternatives to natural strigolactones for agricultural benefits.
• To evaluate the efficacy of new analogues as suicidal germination agents for parasitic weeds.

Main Methods:

• Synthesis of eight hybrid-type SL analogues by coupling auxin ester with various D-rings (mono-, di-, and trimethylated).
• Bioassays conducted on parasitic weeds (Striga hermonthica, Orobanche minor, Phelipanche ramosa) to assess seed germination.
• Utilized classical seed counting and colorimetric methods for germination activity assessment.

Main Results:

• Hybrid SL analogues with a natural monomethylated D-ring exhibited appreciable to good germination activity against all tested parasitic weed species.
• Derivatives with a trimethylated D-ring showed no significant activity.
• Dimethylated derivatives displayed slight activity, particularly against Phelipanche ramosa.

Conclusions:

• Successfully prepared novel hybrid-type SL analogues derived from auxins.
• These analogues demonstrate potential as effective suicidal germination agents for parasitic weed control.
• Ease of preparation and relevant bioactivity make these compounds attractive for agricultural applications.