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. 2022 Nov 12;72(2):181–194. doi: 10.1007/s00011-022-01658-z

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Fig. 1 — Synthetic route of compounds IIIa-IIIc. (i) K₂CO₃, acetone, 48 h; reflux; (ii) piperidine, K₂CO₃, KI, CH₃CN, 24 h, reflux; (iii) 15% KOH, EtOH, 0.5–4 h, rt