title: Di-heterometalation of thiol-functionalized peptide nucleic acids.
abstract: As a proof-of-principle, two hetero-bimetallic PNA oligomers containing a ruthenium(II) polypyridyl and a cyclopentadienyl manganese tricarbonyl complex have been prepared by serial combination of solid-phase peptide coupling and in-solution thiol chemistry. Solid-phase N-terminus attachment of Ru(II)-polypyridyl carboxylic acid derivative, C1, onto the thiol-functionalized PNA backbone (H-a-a-g-t-c-t-g-c-linker-cys-NH 2) has been performed by standard peptide coupling method. As two parallel approaches, the strong affinity of thiols for maleimide and haloacetyl group has been exploited for subsequent post-SPPS addition of cymantrene-based organometallic cores, C2 and C3. Michael-like addition and thioether ligation of thiol functionalized PNA1 (H-gly-a-a-g-t-c-t-g-c-linker-cys-NH 2) and PNA2 (C1-a-a-g-t-c-t-g-c-linker-cys-NH 2) to cymantrene maleimide and chloroacetyl derivatives, C2 and C3, respectively, has been performed. The synthesized ruthenium(II)-cymantrenyl PNA oligomers have been characterized by mass spectrometry (ESI-MS) and IR spectroscopy. The distinct Mn-CO vibrational IR stretches, between 1,924-2,074 cm (-1) , have been used as markers to confirm the presence of cymantrenyl units in the PNA sequences and the purity of the HPLC-purified PNA thioethers assessed using LC-MS.
authors: Institute of Inorganic Chemistry, University of Zurich, Zurich, Switzerland.
authors: Tanmaya
authors: T
authors: Joshi
authors: Malay
authors: M
authors: Patra
authors: Leone
authors: L
authors: Spiccia
authors: Gilles
authors: G
authors: Gasser
mesh_terms: D013058:Mass Spectrometry; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D020135:Peptide Nucleic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D017975:Ruthenium Compounds / Q000737:chemistry*; D060327:Solid-Phase Synthesis Techniques; D013055:Spectrophotometry, Infrared; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D020135:Peptide Nucleic Acids; D017975:Ruthenium Compounds; D013438:Sulfhydryl Compounds
keywords: cymantrene; hetero-metalation; organometallics; peptide nucleic acids; ruthenium; thioether