Inova unity 200 spectrometer

The synthesis of esters IDETRL and IDELIP was reported in Scheme 1. Commercially-available idebenone and trolox or lipoic acid were reacted to obtain esters IDETRL and IDELIP, respectively, in the presence of 4-DMAP and DCC in dry acetonitrile as solvent. This procedure had already been adopted for the preparation of IDETRL, known as Fe-Aox29 [47 (link)]; in this case, some slight modifications were used.
Infrared spectra were recorded on a Perkin Elmer series FTIR 1600 spectrometer (Milan, Italy) in NaBr disks. ¹H-NMR spectra were performed on a Varian Inova Unity 200 spectrometer (200 MHz) (Milan, Italy) in DMSO-d₆ or CDCl₃ solution. Chemical shifts are given in δ values (ppm), using tetramethylsilane as the internal standard; coupling constants (J) are given in Hz. Signal multiplicities are characterized as s (singlet), t (triplet), and m (multiplet). Reaction progress and purity of all the synthesized compounds were checked on TLC (an aluminum sheet coated with silica gel 60 F₂₅₄, Merck, Darmstadt, Germany) and visualized by UV light at 254 and 366 nm as wavelength). Purification of synthesized compounds by flash column chromatography was performed using Merck silica gel (0.040–0.063 mm).

Melting points of newly synthesized derivatives were determined with an Electrothermal IA9200 using glass capillary tubes. Infrared spectra were recorded on a Perkin–Elmer FT IR 1600 spectrometer in KBr disks. Elemental analyses for C, H, and N were within 70.4% of theoretical values and were performed on a Carlo Erba Elemental Analyzer Mod. 1108 apparatus. ¹H NMR spectra were recorded at 200 MHz on a Varian Inova Unity 200 spectrometer in DMSO-d₆ or chloroform-d solution. Chemical shifts are given in δ values (ppm), using tetramethylsilane as the internal standard; coupling constants (J) are given in hertz (Hz). Signal multiplicities are characterized as s (singlet), d (doublet), t (triplet), q (quartet), m (multiplet), and br (broad signal). All the synthesized compounds were tested for purity on TLC (aluminum sheet coated with silica gel F254, Merck) and visualized by UV (λ 254 and 366 nm).