206119-91-7

Basic information

• Product Name: 1,2-Pyrrolidinedicarboxylic acid, 4-methyl-5-oxo-, bis(1,1-dimethylethyl) ester, (2S,4R)-
• CAS NO: 206119-91-7
• Molecular Formula: C15H25NO5
• Molecular Weight: 299.367
• Mol File: 206119-91-7.mol
• Article Data: 6

Chemical Properties

• CAS DataBase Reference: 1,2-Pyrrolidinedicarboxylic acid, 4-methyl-5-oxo-, bis(1,1-dimethylethyl) ester, (2S,4R)-(CAS DataBase Reference)
• NIST Chemistry Reference: 1,2-Pyrrolidinedicarboxylic acid, 4-methyl-5-oxo-, bis(1,1-dimethylethyl) ester, (2S,4R)-(206119-91-7)
• EPA Substance Registry System: 1,2-Pyrrolidinedicarboxylic acid, 4-methyl-5-oxo-, bis(1,1-dimethylethyl) ester, (2S,4R)-(206119-91-7)

Safety Data

• Hazardous Substances Data: 206119-91-7(Hazardous Substances Data)

Upstream product

• 91229-91-3 tert-butyl (S)-N-tert-butoxycarbonylpyroglutamate 
• 333-27-7 methyl trifluoromethanesulfonate 
• 74-88-4 methyl iodide 

Relevant articles and documents

Design and Synthesis of Building Blocks for PPII-Helix Secondary-Structure Mimetics: A Stereoselective Entry to 4-Substituted 5-Vinylprolines

In the course of our studies towards the synthesis of proline-based secondary-structure mimetics, we developed a straightforward methodology for the diastereoselective preparation of 4-alkyl-5-vinyl-substituted proline derivatives. Starting from N-Boc-protected tert-butyl pyroglutamate, α-alkylation, lactam reduction and acid-catalyzed methanolysis afforded 4-alkyl-5-methoxyproline derivatives. After BF3-induced formation of an N-acyl-iminium intermediate, the introduction of the 5-vinyl side chain was achieved with high diastereoselectivity by using vinylmagnesium bromide in the presence of AlCl3 or CuBr·SMe2 to afford either the cis- or the trans-product, respectively. The utility of the method was demonstrated in the rapid and efficient construction of new diproline mimetics rigidified in a polyproline-type II helix (PPII) conformation.

Stereochemical assignments of the chlorinated residues in victorin C

Victorins are cyclic pentapeptide natural products isolated from the fungus Cochliobus victoriae. Using a combination of synthesis and spectroscopic methods we have assigned the geometry of the vinyl chloride residue and determined the stereochemistry of the 5,5-dichloroleucine moiety. Georg Thieme Verlag Stuttgart.

Unusual stereoselectivity in the alkylation of pyroglutamate ester urethanes

Previous studies on the alkylation of pyroglutamate ester urethanes have led to a consensus that alkylation at C-4 occurs to give a mixture of diastereoisomers, the major isomer of which usually has the alkyl group trans to the ester group at C-2. We have now discovered that this generalisation is not invariably correct and that, although for SN1-type electrophiles stereoselectivity is in fact trans, SN2-type electrophiles can give the thermodynamically less stable cis compounds as the predominant products. Use of the bulky proton source 2,6-di-tert-butylphenol to quench these reactions yields the cis isomers as the only products in good yield, thus making direct alkylation of pyroglutamic acid derivatives a useful alternative to our hydrogenation approach to these synthons.