Synthesis and structural reconfirmation of bacillamide B.

Area of Science:

• Organic Chemistry
• Natural Product Synthesis

Background:

• Bacillamide B is a natural product with potential biological significance.
• Efficient synthetic routes to complex natural products are crucial for further study.

Purpose of the Study:

• To develop a concise and efficient total synthesis of bacillamide B.
• To reconfirm the absolute configuration and revise the specific optical rotation of bacillamide B.

Main Methods:

• Total synthesis starting from L-cystine.
• A key one-pot, four-step sequence involving disulfide cleavage, thiocarbonylation, Staudinger reduction, and aza-Wittig reaction.
• Utilized β-azido disulfide and carboxylic acid substrates.

Main Results:

• Achieved a 30% overall yield for the total synthesis of bacillamide B.
• Successfully established a novel cascade reaction for thiazoline formation.
• Reconfirmed the natural product's absolute configuration as S and revised the specific optical rotation to (-).

Conclusions:

• A concise and efficient synthetic route to bacillamide B has been established.
• The developed one-pot method offers a valuable strategy for thiazoline synthesis.
• The stereochemical assignment of bacillamide B has been definitively revised.