Isatin

Harlan 8640 Teklad 22/5 rodent diets were used for both control and 0.7% adenine supplemented diets (Madison, WI). Indoxyl sulfate was obtained from gold biotechnology (Olivette, MO). P-cresyl glucuronide and equol 7-glucuronide were purchased from Toronto Research Chemicals (Toronto, ON, Canada) and β-glucuronidase from Helix pomatia (G-7051), pyrocatechol, p-cresol and 4-ethylphenol were obtained from Sigma-Aldrich (St. Louis, MO). Flurazepam was purchased from Cerilliant (Round Rock, TX). Isatin was purchased from Alfa Aesar (Ward Hill, MA). P-cresyl sulfate, phenyl sulfate and 4-ethyl phenyl sulfate were synthesized as previously described58 (link). AST-120 was a kind gift from the Kureha Corporation (Tokyo, Japan).

N-methyl pyrrolidine (98%, Alfa Aesar, Haverill, MA, USA), N-methyl piperidine (99%, Alfa Aesar, Haverill, MA, USA), 1,5 dibromopentane (98%, Alfa Aesar, Haverill, MA, USA), potassium carbonate (K₂CO₃, 99%, Merck, Rowe, NJ, USA), biphenyl (99%, Alfa Aesar, Haverill, MA, USA), 2,2,2-trifluoroacetophenone (98%, Alfa Aesar, Haverill, MA, USA), isatin (98%, Alfa Aesar, Haverill, MA, USA), trifluoroacetic acid (TFA, 99%, Alfa Aesar, Haverill, MA, USA), trifluoromethanesulfonic acid (TFSA, 99%, Fluorochem, Derbyshire, UK), potassium hydroxide (+85% pellets, Merck, Rowe, NJ, USA), acetonitrile, (99.5%, Scharlab, Quezon City, Philippines), dimethylsulfoxide (DMSO, Scharlab, Quezon City, Philippines), N-methyl pyrrolidone (NMP, Scharlab, Quezon City, Philippines) acetone (Scharlab, Quezon City, Philippines), diethyl ether (Sigma Aldrich, St. Louis, MO, USA), methanol (Sigma Aldrich, St. Louis, MO, USA), dichloromethane (DCM, Scharlab, Quezon City, Philippines), dmso-d₆ (99.80 atom% Deutero, Kastellaun, Germany) were all used as received.