It is formed by lactonization of 4-" O "-caffeoylquinic acid during the roasting process.
2.
The polyketide chain produced is electronically capable to go through a lactonization and a diels alder cyclization, as shown below.
3.
The above figure shows a carboxylic acid directed diastereoselective lactonization of tetrahydrogibberellic acid via a C-H oxidation to form a butyrolactone derivative.
4.
After being released from the thioesterase domain as a long fatty acid chain, the characteristic ?, ?-unsaturated lactone moiety is formed through a lactonization step to result in the final structure.
5.
A functional stereodivergent organocatalyzed IMA / lactonization transformation in the synthesis of substituted dihydrofurans and tetrahydrofurans has been studied for its ability to construct important structural motifs in numerous natural products ( figure 2 ).
6.
In 1977, Samuel Danishefsky and coworkers were able to synthesize the tumor growth inhibitors " dl "-vernolepin and " dl "-vernomenin via a multistep process in which a lactonization was employed.
7.
A second genetically modified microbe species, such as mutant " Erwinia ", among others, oxidises sorbose into 2-ketogluconic acid ( 2-KGA ), which can then undergo ring-closing lactonization via dehydration.
8.
Germacrene acid could then be hydoxylated and undergo lactonization to form ( + )-costunolide, a branching point for the biosynthesis of sesquiterpene lactones . ( "'Fig . 2 "') From here, the biosynthesis of guaianolides can follow two proposed pathways.
मोबाइल