138219-39-3Relevant academic research and scientific papers
A short formal synthesis of three epimers of penmacric acid
Sikriwal, Dimpy,Kant, Ruchir,Maulik, Prakas R.,Dikshit, Dinesh K.
experimental part, p. 6167 - 6173 (2010/10/02)
An extremely short formal synthesis of three epimers of penmacric acid is accomplished starting from pyroglutamate in one or two steps. Stereochemical outcome in the reaction of Li and Ti enolates of pyroglutamate with imines is found to be dependent on both chelation and steric factors.
Electrophilic amination of enolates with oxaziridines: Effects of oxaziridine structure and reaction conditions
Armstrong, Alan,Edmonds, Ian D.,Swarbrick, Martin E.,Treweeke, Nigel R.
, p. 8423 - 8442 (2007/10/03)
A range of N-alkoxycarbonyl- and N-carboxamido-oxaziridines has been prepared to test the effects of oxaziridine structure on yields of enolate amination product. Side-products arising from reaction of aldehyde-derived oxaziridines with base were identified, while a ketone-derived oxaziridine afforded moderate yields of amination product with stabilised carbanions.
Catalytic, asymmetric Mannich-type reactions of α-imino esters bearing readily removable substituents on nitrogen
Nakamura, Yoshitaka,Matsubara, Ryosuke,Kiyohara, Hiroshi,Kobayashi, Shu
, p. 2481 - 2484 (2007/10/03)
(Matrix presented) Catalytic, enantioselective Mannich-type reactions of α-imino esters bearing readily removable substituents on nitrogen are described. Several N-carbamate-protected α-imino esters, which are readily prepared from 2-bromoglycine esters using a polymer-supported amine, reacted with silicon enolates to afford the desired adducts in high yields with high enantioselectivity using a copper(II)-diamine complex. Easy deprotection of the product amine and transformation to free o-amino acid derivatives have also been demonstrated.
Cross-metathesis of unsaturated α-amino acid derivatives
Biagini, Stefano C. G.,Gibson, Susan E.,Keen, Stephen P.
, p. 2485 - 2499 (2007/10/03)
Cross-metathesis of homoallylglycine derivatives with aryl- and alkyl-substituted alkenes using the ruthenium catalyst (Cy3P)2Cl2Ru=CHPh 1 has been achieved in 43-55 and 55-66% yield respectively. Allylglycine, vinylglycine and dehydroalanine derivatives have also been examined. Whilst cross-metathesis of allylglycine derivatives with alkyl-substituted alkenes using catalyst 1 may be regarded as a synthetically useful procedure, cross-metathesis reactions of vinylglycine and dehydroalanine derivatives using catalyst 1 are non-viable. Attachment of FmocHagOH 13 to a capped Wang resin, cross-metathesis with dodec-1-ene, and product removal from the resin gives the cross-metathesis product in 74% yield based on FmocHagOH.
Synthesis of polysubstituted indoles and indolines by means of zirconocene-stabilized benzyne complexes
Tidwell, Jeffrey H.,Buchwald, Stephen L.
, p. 11797 - 11810 (2007/10/02)
The development of a new method for the regiospecific synthesis of polysubstituted indoles and indolines is reported. The key steps involve the generation of zirconocene-stabilized benzyne complexes and subsequent intramolecular olefin insertion reactions to provide tricyclic indoline zirconacycles. The zirconacyclic intermediates were cleaved with iodine to yield diiodo indolines, which were converted to a wide variety of indole and indoline products, such as analogs of tryptamine, serotonin, tryptophan, and the pharmacophore of CC-1065.
