3.1. Chemistry

The microwave reactor was a monomode system (Discover, CEM) with focused waves operating at 2.45 GHz. Melting points were determined on an Electrothermal IA9300 melting point digital apparatus and were reported uncorrected. Infrared (IR) spectra were obtained in KBr pellets or neat liquid films with a Perkin–Elmer Paragon FTIR 1000 PC spectrometer. ¹H and ¹³C-NMR spectra were recorded on a Bruker AC 250 or AVANCE 400 spectrometer in DMSO-d₆ as solvent. Chemical shifts (δ) were reported in part per million (ppm) relative to tetramethylsilane as internal standard. The splitting pattern abbreviations are as follows: s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; dd, doublet of doublet; td, triplet of doublet. Coupling constants J were given in Hz. Mass spectral (MS) analysis was performed on a quadrupole H.P. 5889A instrument using EI mode at 70 eV. Microanalyses were performed on a Perkin–Elmer CHN 240 apparatus. All reactions were monitored by TLC, using 0.25 mm-thick precoated silica gel plates (E. Merck, Darmstadt, Germany). Compounds were purified by column chromatography using silica gel 60 as a stationary phase. All common chemicals and solvents utilized were reagent grade and purchased from Sigma–Aldrich (Saint Quentin, France).

The synthesis of key intermediates 9a–e and 10a–e was previously described by IICiMed (Nantes) [27]. 1-Hydroxymethyl-1H-benzotriazole (2), 1-chloromethyl-1H-benzotriazole (3), and 1-(1H-benzotriazol-1-yl-methyl)-1H-indole (4) were previously published [42,43] and some spectral data were added to be as precise as possible.