A series of ortho- and para-substituted L-phenylalanylpuromycin analogues were synthesized and evaluated as substrates for the peptidyltransferase reaction of Escherichia coli ribosomes. Kinetic results reveal that substitution of the p-methoxy group of the puromycin molecule alters the peptidyltransferase activity of the molecule with the following decreasing order of substrate efficiencies: p-NH2 > p-NHCOCH3 > p-NO2 = p-NHCO(CH2)2CH3 > p-NHCOCH2Br. However, the inability of the ribosome to tolerate a nitro group at the ortho position of the phenylalanine ring precluded the use of the photosensitive puromycin analogue, 2-nitro-4-azidophenylalanylpuromycin aminonucleoside (7a), as a photoaffinity label for the peptidyltransferase site.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of medicinal chemistry|
|State||Published - Mar 1981|