An ester enolate-Claisen rearrangement route to substituted 4-alkylideneprolines. studies toward a definitive structural revision of lucentamycin A.

  title={An ester enolate-Claisen rearrangement route to substituted 4-alkylideneprolines. studies toward a definitive structural revision of lucentamycin A.},
  author={Sujeewa Ranatunga and Jinsoo Kim and Ujjwal Pal and Juan R. Del Valle},
  journal={The Journal of organic chemistry},
  volume={76 21},
Substituted 4-alkylideneprolines represent a rare class of naturally occurring amino acids with promising biological activities. Lucentamycin A is a cytotoxic, marine-derived tripeptide that harbors a 4-ethylidine-3-methylproline (Emp) residue unique among known peptide natural products. In this paper, we examine the synthesis of Emp and related 4-alkylideneprolines employing a versatile ester enolate-Claisen rearrangement. The scope and selectivity of the key rearrangement reaction are… 
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