Total Synthesis of Orbiculamide A.

Area of Science:

• Organic Chemistry
• Medicinal Chemistry
• Natural Product Synthesis

Background:

• Orbiculamide A is a macrocyclic peptide with demonstrated antimitotic and antileukemic activities.
• The molecule possesses complex structural features, notably a 2-bromo-5-hydroxytryptophan residue, posing significant synthetic hurdles.

Purpose of the Study:

• To report the first total synthesis of Orbiculamide A.
• To develop and implement a novel synthetic strategy to overcome existing challenges in Orbiculamide A synthesis.

Main Methods:

• A chemoselective, late-stage bromodesilylation strategy was central to the synthetic approach.
• The synthesis involved meticulous planning to incorporate the challenging 2-bromo-5-hydroxytryptophan moiety.

Main Results:

• The first successful total synthesis of Orbiculamide A was accomplished.
• The developed strategy effectively addressed the synthetic challenge posed by the brominated tryptophan residue.

Conclusions:

• This synthesis provides a crucial foundation for the preparation of related natural products.
• The methodology enables scaffold diversification for the development of novel medicinal peptides.