We don't have synonyms for mean streets yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are main streets.
(n) :
(of an urban environment) A district or set of locales in which there is a high incidence of poverty, crime, disrepair, antisocial behavior, or other adverse conditions.
(n) :
(of an urban environment) A district or set of locales in which there is a high incidence of poverty, crime, disrepair, antisocial behavior, or other adverse conditions.