Solid-Phase Combinatorial Synthesis and Biological Evaluation of Destruxin E Analogues

Area of Science:

• Medicinal Chemistry
• Organic Synthesis
• Cell Biology

Background:

• Destruxin E is a cyclodepsipeptide with biological activity.
• Understanding its structure-activity relationships is essential for developing targeted therapeutics and molecular probes.
• Osteoclast-like multinuclear cells (OCLs) are relevant models for studying bone resorption and related diseases.

Purpose of the Study:

• To develop a solid-phase combinatorial synthesis of destruxin E analogues.
• To investigate the structure-activity relationships of destruxin E analogues concerning OCLs.
• To design and synthesize azido-containing analogues for use as molecular probes for target identification.

Main Methods:

• Solid-phase combinatorial synthesis using a split and pool method on SynPhase Lanterns.
• Solution-phase macrolactonization using 2-methyl-6-nitrobenzoic anhydride and 4-(dimethylamino)pyridine N-oxide.
• Epoxide formation in the side chain to yield 18-membered destruxin E analogues.
• Biological evaluation of synthesized analogues on OCLs.
• Design and synthesis of azido-containing analogues for molecular probing.

Main Results:

• Successfully synthesized 18-membered destruxin E analogues via solid-phase combinatorial methods.
• Identified the N-MeAla residue as critical for inducing morphological changes in OCLs.
• Developed azido-containing analogues, with analogue 15b (Lys(N3) replacing Ile) showing significant OCL morphological changes.
• Demonstrated tolerance for modification around the Ile residue for chemical tag attachment.

Conclusions:

• Solid-phase combinatorial synthesis is a viable approach for generating destruxin E analogues.
• The N-MeAla residue plays a key role in the biological activity of destruxin E on OCLs.
• Azido-containing analogues serve as effective molecular probes and can be modified for target identification of destruxin E.