title: Synthesis and microbiological activities of some monohalogenated analogs of tyrosine.
abstract: 2-Chlorotyrosine and 2-bromotyrosine, as well as the previously reported 2-fluorotyrosine, were synthesized by hydrolysis of the condensation products from the appropriate benzyl bromide and ethyl acetamidomalonate and were compared with the corresponding 3-halotyrosines as growth inhibitors of Escherichia coli 9723, Streptococcus faecalis 8043 and Lactobacillus plantarum 8014. In contrast to the 2- and 3-fluorotyrosines which were equally effective as growth inhibitors, the 2-chloro- and 2-bromotyrosines were much more effective than the 3-chloro- and 3-bromotyrosines in inhibiting the growth of the three microorganisms. For each of the assay organisms, the growth inhibitions of all three 2-halotyrosines were reversed competitively in varying degrees by tyrosine.
mesh_terms: D001966:Bromine; D002713:Chlorine; D013293:Enterococcus faecalis / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D007778:Lactobacillus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000494:pharmacology; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology
chemical_list: D014443:Tyrosine; D010649:Phenylalanine; D002713:Chlorine; D001966:Bromine