11c r pk11195

[¹¹C]-(R)-PK11195 was synthesized using the previously reported method with a few modifications.^{[33 (link)]} The precursor and the cold-standard of [¹¹C]-(R)-PK11195 were purchased from ABX (Radeberg, Germany); the other chemicals were obtained from Sigma-Aldrich Korea (Kyunggi-do, Korea). Briefly, (R)-N-desmethyl-PK11195 (the precursor of [¹¹C]-(R)-PK11195, 1 mg, 2.8 μmol) and sodium hydride (60% in mineral oil, 7 mg, 486 μmol) were dissolved in 500 μL of dimethyl sulfoxide in a reaction vial. [¹¹C]CH₃I was bubbled into the reaction vial for 10 minutes, and the reaction mixture was allowed to proceed for an additional 5 minutes. The reaction mixture was purified by preparative high-performance liquid chromatography (HPLC) (Xterra C18 column, 10 × 250 mm², 10 μm, Waters Corp.; Milford, MA) with the eluent (water:ethanol = 55:45, 5 mL/min). The final product solution was reconstituted with 10 mL of a saline solution. The purity of the final product was checked by analytical HPLC (YMC-Triart C18 column, 4.6 × 100 mm², 3 μm, YMC Co., Ltd.; Kyoto, Japan) with the eluent (water:MeCN = 40:60, 1 mL/min). The radioactivity of [¹¹C]-(R)-PK11195 was 5.7 ± 1.8 GBq (156.7 ± 51.3 mCi [n = 10]); the specific activity was 215.2 ± 93.7 GBq/μmol (5.8 ± 2.5 Ci/mol [n = 10]). The total synthesis time, including formation and purification, was less than 40 minutes from the end of bombardment.

[¹¹C]-(R)-PK11195 was synthesized using a previously reported method with a few modifications [24 (link)]. The precursor and the cold-standard of [¹¹C]-(R)-PK11195 were purchased from ABX (Radeberg, Germany); the other chemicals were obtained from Sigma-Aldrich Korea (Kyunggi-do, Korea). Briefly, (R)-N-desmethyl-PK11195 (the precursor of [¹¹C]-(R)-PK11195, 1 mg, 2.8 μmol) and sodium hydride (60% in mineral oil, 7 mg, 486 μmol) were dissolved in 500 μL of dimethyl sulfoxide in a reaction vial. [¹¹C]CH₃I was bubbled into the reaction vial for 10 minutes, and the reaction mixture was allowed to proceed for an additional 5 minutes. The reaction mixture was purified by preparative high-performance liquid chromatography (HPLC) (Xterra C18 column, 10 × 250 mm², 10 μm, Waters Corp.; Milford, MA) with the eluent (water:ethanol  =  55:45, 5 mL/min). The final product solution was reconstituted with 10 mL of a saline solution. The purity of the final product was checked by analytical HPLC (YMC-Triart C18 column, 4.6 × 100 mm², 3 μm, YMC Co., Ltd.; Kyoto, Japan) with the eluent (water:MeCN  =  40:60, 1 mL/min). The radioactivity of [¹¹C]-(R)-PK11195 was 5.7 ± 1.8 GBq (156.7 ± 51.3 mCi [n  =  10]); the specific activity was 215.2 ± 93.7 GBq/μmol (5.8 ± 2.5 Ci/mol [n  =  10]). The total synthesis time, including formation and purification, was less than 40 minutes from the end of bombardment.