Synthesis and characterisation of hetero-bimetallic organometallic phenylalanine and PNA monomer derivatives.
The rational, sequential synthesis of two hetero-bimetallic derivatives of the amino acid phenylalanine and one thymine (T) peptide nucleic acid (PNA) monomer is reported. Ferrocene carboxylic acid and (eta-ethene)bis(triphenylphosphine)platinum(0) were successfully reacted with propargylamide amino acid (1a and 1b) or a T PNA monomer derivative (6) to give the expected three bimetallic compounds 4a, 4b and 9 in good yield. An enzymatic route using cross-linked enzyme crystals (CLEC) of subtilopeptidase A in organic solvents gave the ferrocene carboxylate phenylalanine propargylamide precursor (Fc-CO-Phe-NH-CH(2)-CCH, 3a) in comparable yield and purity to the traditional deprotection-peptide coupling sequence. (31)P NMR spectra of these bioorganometallics showed two doublets with (195)Pt satellites corresponding to two chemically different (31)P atoms. Interestingly, in the case of the T PNA monomer derivative 9, these signals were also doubled in a 60 : 40 ratio as a consequence of the existence of two slowly interconverting isomers in solution. Furthermore, the single-crystal X-ray structures of 3a and the hetero-bimetallic phenylalanine derivative 4b were determined, showing the presence of the two organometallics moieties separated by ca. 8.5 A in 4b as well as illustrating the stability of such compounds.
Gasser
Gilles
G
Lehrstuhl für Anorganische Chemie I-Bioanorganische Chemie, Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum, Bochum, Germany.
Brosch
Oliver
O
Ewers
Alexandra
A
Weyhermüller
Thomas
T
Metzler-Nolte
Nils
N
D000480:Alkynes / Q000138:chemical synthesis / Q000737:chemistry; D018360:Crystallography, X-Ray; D005296:Ferrous Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D000075163:Metallocenes; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D020135:Peptide Nucleic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D010649:Phenylalanine / Q000138:chemical synthesis* / Q000737:chemistry; D010720:Phosphines / Q000138:chemical synthesis / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D013941:Thymine / Q000138:chemical synthesis* / Q000737:chemistry
D000480:Alkynes; D005296:Ferrous Compounds; D000075163:Metallocenes; D009942:Organometallic Compounds; D020135:Peptide Nucleic Acids; D010720:Phosphines; D010649:Phenylalanine; D010984:Platinum; C044646:phosphine; D013941:Thymine; C004998:ferrocene