4 methylphenol

Methanol (HPLC grade) was bought from Fisher (USA). Methoxamine hydrochloride and N-methyl-N-(trimethylsilyl) trifluoracetamide (MSTFA) were obtained from Sigma (USA). Compositions of the nutrient solution, Pb(NO₃)₂, NaOH, HCl, NaNO₃, l-alanine, l-proline, oxalic acid, glyceric acid, 2-hydroxyacetic acid, glycerol, diethyleneglycol, 4-methylphenol and 2-methoxyphenol (analytic grade) and pyridine (HPLC grade) were purchased from Sinopharm Chemical Reagent Co., Ltd. (ShangHai, China).

Nitrobenzene (+99%), 1,4-diNitrobenzene (+98%), 4-chloroaniline (+98%) and naphthalene (+99%) were purchased from Acros Organics Co.; 3-Nitroaniline (+98%) was purchased from Sigma-Aldrich Chemistry Co.; 2-Chlorophenol (+99%), 4-chlorophenol (+99%), 2-chloroaniline (+98%), 2-nitroaniline (+99%) and 4-methylaniline (+99.7%) were purchased from Aladdin Reagent Co.; 4-MethylNitrobenzene (+99.5%), 4-chlosroNitrobenzene (+98%), phenanthrene (+98%) and pyrene (+97%) were purchased from Fluka Chemistry Co.; 1,2-DiNitrobenzene (+98%), 1,3-dinitro benzene (+99%) and 1,3,5-triNitrobenzene (wetted with 40% water) were purchased from Tokyo Chemical Industry Co.; 2,4-Dichlorophenol (+99.5%), 4-methylphenol (+98%), 2-nitrophenol (+99%), 3-nitrophenol (+99%), 4-nitrophenol (+99.5%) and 4-nitroaniline (+99.5%) were purchased from Sinopharm Chemical Reagent Co.; Aniline (+99.5%) was purchased from Shanghai Reagent Co.; and phenol (+99.7%) was purchased from Hangzhou Shuanglin Chemical Co. All these aromatic chemicals were used as received. The selected properties including water solubility (S_w), octanol-water partitioning coefficients (logK_ow), molecular weight, maximum absorption wavelength (λ_max), dissociated constant (pK_a) of the 25 investigated aromatic chemicals are listed in Table S3.