Photoinduced electron transfer on ?2-sheet cyclic peptides
Gramicidin S analogues that contain a single pyrenyl group and a single p-nitrophenyl group at different positions were synthesized. Photoinduced electron transfer (ET) from an excited pyrenyl group located at the fourth position to a nitrophenyl group located at five different positions was investigated on the ?2-sheet chains of the cyclic peptides. The observed ET rate constants displayed a complex dependence on the number of spacer units or on the edge-to-edge distance between the two aromatic groups. The ET rate constants, however, showed a reasonable linear relationship with the equivalent ??-distances calculated from the Beratan-Onuchic tunneling pathway model, if through-hydrogen-bond ET was taken into account. The results support the applicability of the tunneling pathway model on both helix and ?2-sheet model peptides.
Sasaki, Hiroshi,Makino, Maki,Sisido, Masahiko,Smith, Trevor A.,Ghiggino, Kenneth P.
A practical synthesis of gramicidin S and sugar amino acid containing analogues
A practical gram-scale and high-yielding synthesis of the antimicrobial peptide gramicidin S is presented. An Fmoc-based solid-phase peptide synthesis protocol is employed for the generation of the linear decapeptide precursor, which is cyclized in solution to afford the target compound. The versatility of our method is demonstrated by the construction of eight gramicidin S analogues (15a-h) having nonproteinogenic sugar amino acid residues (4-7) incorporated in the turn regions.
Grotenbreg, Gijsbert M.,Kronemeijer, Martijn,Timmer, Mattie S. M.,El Oualid, Farid,Van Well, Renate M.,Verdoes, Martijn,Spalburg, Emile,Van Hooft, Peter A. V.,De Neeling, Albert J.,Noort, Daan,Van Boom, Jacques H.,Van Der Marel, Gijsbert A.,Overkleeft, Herman S.,Overhand, Mark
p. 7851 - 7859
(2007/10/03)
More Articles about upstream products of 1054661-52-7