title: Synthesis of stable C-linked ferrocenyl amino acids and their use in solution-phase peptide synthesis.
abstract: Incorporation of ferrocenyl group to peptides is an efficient method to alter their hydrophobicity. Ferrocenyl group can also act as an electrochemical probe when incorporated onto functional peptides. Most often, ferrocene is incorporated onto peptides post-synthesis via amide, ester or triazole linkages. Stable amino acids containing ferrocene as a C-linked side chain are potentially useful building units for the synthesis of ferrocene-containing peptides. We report here an efficient route to synthesize ferrocene-containing amino acids that are stable and can be used in peptide synthesis. Coupling of 2-ferrocenyl-1,3-dithiane and iodides derived from aspartic acid or glutamic acid using n-butyllithium leads to the incorporation of a ferrocenyl unit to the δ-position or ε-position of an α-amino acid. The reduction or hydrolysis of the dithiane group yields an alkyl or an oxo derivative. The usability of the synthesized amino acids is demonstrated by incorporating one of the amino acids in both C-terminus and N-terminus of tripeptides in solution phase.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
authors.forename: Anijamol T
authors.initials: AT
authors.lastname: Philip
authors.affiliation: Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
authors.forename: Shibin
authors.initials: S
authors.lastname: Chacko
authors.affiliation: Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Ramapanicker
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D001224:Aspartic Acid / Q000737:chemistry; D005296:Ferrous Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D018698:Glutamic Acid / Q000737:chemistry; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000596:Amino Acids; D005296:Ferrous Compounds; D009942:Organometallic Compounds; D010455:Peptides; C434823:n-butyllithium; D001224:Aspartic Acid; D018698:Glutamic Acid
keywords: amino acids; dithiane; ferrocene; peptides