Synthesis of Mono(thio)-, Bis(thio)- And Mono(amino)-Substituted 1,4-Benzoquinones

Twelve thio- and amino- benzoquinones (3a-d, 5a, 5b, 7d, 8d, 10e, 11e, 13e and 13f) were synthesized from benzoquinones (p-benzoquinone 1, p-toluquinone 6 and 2-tert-butyl-1,4-benzoquinone 12) with thiols or primary amines. Among them, compounds 3a-3d and 5a,b have mono(thio)- and bis(thio)- substituted-benzoquinone structures, respectively. The compounds 2-(3,4-dimethylphenylthio)-6- (tetradecylthio)cyclohexa-2,5-diene-1,4-dione (5a) and 2-(3,4- dimethoxyphenylthio)-6-(tetradecylthio)cyclohexa-2,5-diene-1,4-dione, (5b) include two different thio- groups in each of them. Compounds 7d and 8d have 5-methyl- and 6-methyl- 2-thio-substituted-benzoquinone structures, respectively, while compounds 10e and 11e have 5-methyland 6-methyl- 2-benzylamino-substituted-benzoquinone structures, respectively. The compounds 13e and 13f include the 6-tert-butyl-2- benzylamino-substituted-1,4-benzoquinone skeleton. Twelve products were characterized, using FTIR, UV/Vis, MS(ESI), 1H and 13C NMR and elemental analysis. Antibacterial activity of compound 3d has been evaluated against Escherichia coli (E. coli)