Chn 900 elemental analyzer

Proton (¹H) and carbon (¹³C) NMR spectra were recorded on a Brüker 400 Ultra-shield™ spectrometer (Brüker, Rheinstetten, Germany) using DMSO-d₆ or CDCl₃ as solvent. IR spectra were recorded on a Thermo Nicolet FT-IR Nexus spectrophotometer (Thermo Nicolet, Madison, WI, USA) using KBr pellets for solid samples or NaCl plates for oil compounds. Elemental analysis was performed on a LECO CHN-900 Elemental Analyzer (LECO, Saint Joseph, MI, USA). The purity of all final compounds was 99% or higher. Chemicals were purchased from E. Merck (Darmstadt, Germany), Panreac Química S.A. (Barcelona, Spain), Sigma-Aldrich Quimica, S.A. (Madrid, Spain) and Acros Organics (Janssen Pharmaceuticalaan, Geel, Belgium). The synthesis of 34 out of the 40 compounds analysed in this work has been previously described [28 (link),29 (link)].

Melting points (m.p.) were determined with a FP82 + FP80 apparatus (Mettler, Greifensee, Switzerland). The NMR spectra (¹H/400 MHz and ¹³C/100 MHz, Supplementary Materials) were recorded on a Ultrashield^TM 400 spectrometer (Bruker, Rheinstetten, Germany). The samples were dissolved in DMSO-d₆ or CDCl₃ and TMS was used as internal standard. IR spectra were obtained on a FT-IR Nexus spectrophotometer (Thermo Nicolet, Madison, WI, USA) using KBr pellets for solids or NaCl plates for oil compounds. Elemental analysis was performed on a CHN-900 Elemental Analyzer (LECO, Saint Joseph, MI, USA). HRMS were recorded using an Accurate-Mass TOF LC/MS 6220 (Agilent Technologies, Santa Clara, CA, USA). Only data from compounds 3, 9, 10, 12 and 13 could be obtained due to poor volatilization of the remaining compounds. For TLC assays, Alugram SIL G7UV254 sheets (Macherey-Nagel; Düren, Germany) were used. Column chromatography was performed with silica gel 60 (Merck, Darmstadt, Germany). Chemicals were purchased from E. Merck, Panreac Química S.A. (Montcada i Reixac, Barcelona, Spain), Sigma-Aldrich Quimica, S.A. (Madrid, Spain) and Acros Organics (Janssen Pharmaceuticalaan, Geel, Belgium).