title: Application of carbodiimide mediated Lossen rearrangement for the synthesis of alpha-ureidopeptides and peptidyl ureas employing N-urethane alpha-amino/peptidyl hydroxamic acids.
abstract: Application of the Lossen rearrangement to the synthesis of N-urethane protected alpha-peptidyl ureas and ureidopeptides is reported. The carbodiimide mediated rearrangement of N-Boc/Z/Fmoc protected alpha-amino/peptide hydroxamic acids into isocyanates and coupling of the latter with the amino acid esters/peptide esters have been accomplished in a single-pot to obtain good yields of urea products. Synthesis of the ureidoalanine derivatives via the hydroxamate derivatives of N-protected aspartic acid has also been carried out using the same procedure.
authors.affiliation: Peptide Research Laboratory, Department of Studies in Chemistry, Central College Campus, Bangalore University, Dr B. R. Ambedkar Veedhi, Bangalore, 560001, India.
authors.forename: N
authors.initials: N
authors.lastname: Narendra
authors.forename: Gundala
authors.initials: G
authors.lastname: Chennakrishnareddy
authors.forename: Vommina V
authors.initials: VV
authors.lastname: Sureshbabu
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D002234:Carbodiimides / Q000737:chemistry*; D006877:Hydroxamic Acids / Q000737:chemistry; D055601:Organic Chemistry Phenomena; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D014508:Urea / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D002234:Carbodiimides; D006877:Hydroxamic Acids; D010455:Peptides; D014508:Urea