Methyl isocostate

The Natural Products Journal, 2019, 9(4):262-267.

Synthesis of Spiro-Isoxazolidine Derivatives of Methyl α-Isocostate.[Reference: WebLink]

In recent decades, natural products are an important source of chemotherapeutics as more than half of the effective cancer drugs can be traced to natural origins. Moreover, the modification of natural products is one of the most common and fruitful approaches to obtain novel therapeutic agents in medicinal chemistry.
METHODS AND RESULTS:
Continuing with a research project based on the support of Moroccan plant resources. we report herein the use of α-isocostic acid extracted in enantiomerically pure form from Dittrichia viscosa as a convenient starting material for the synthesis of new eudesmane derivatives. Novel spiro derivatives with a natural scaffold were prepared. Spiro-isoxazolidine derivatives were generated on the exocyclic double bond adjacent to the ester α,β-unsaturated function by 1,3-dipolar cycloaddition of methyl α-isocostate(Methyl isocostate) 1 derived from sesquiterpenic isocostic acid, with nitrones 2.
CONCLUSIONS:
This procedure allowed us to generate enantiomerically pure spiro compounds in one diastereoisomer form with a limited number of steps. These compounds were fully characterized by spectroscopic methods.