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

@article{Ranatunga2011AnEE,
  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},
  year={2011},
  volume={76 21},
  pages={
          8962-76
        }
}
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… 
9 Citations
Rh-Catalyzed Chemoselective [4+1] Cycloaddition Reaction towards Diverse 4-Methyleneprolines.
An efficient synthesis of 4-methyleneproline derivatives has been developed through an Rh-catalyzed [4+1] cycloaddition strategy using 3-methyleneazetidines and diazo compounds. The reaction proceeds
An Ester Enolate—Claisen Rearrangement Route to Substituted 4-Alkylideneprolines. Studies Toward a Definitive Structural Revision of Lucentamycin A.
In the presence of NaN(Tms)2, esters of type (I) and (IX) rearrange to amino acids like (II) and (X) with moderate to high diastereoselectivity.
Structure assignment of lucentamycin E and revision of the olefin geometries of the marine-derived lucentamycins.
TLDR
It is shown that the olefin geometries of the substituted proline functionalities must be revised to (2S,3R,E)-3-methyl-4-ethylideneproline, opposite of that previously reported.
Total synthesis and structural revision of lucentamycin A.
TLDR
The first total synthesis of lucentamycin A is reported, which confirms that the ethylidene substituent in Emp bears an E geometry, in contrast to the originally assigned Z configuration.
Electrophilic warhead-based design of compounds preventing NLRP3 inflammasome-dependent pyroptosis.
TLDR
This study describes the synthesis and chemical tuning of α,β-unsaturated electrophilic warheads toward the development of antipyroptotic compounds targeting molecular components of the NLRP3 inflammasome regulatory pathway and its pharmacological evaluation and structure-activity relationships.

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