Methanol d3

The structural determination of the isolated compounds was based on MS and NMR spectroscopy data. One dimensional NMR (1D-NMR) data consisted of ¹H and ¹³C NMR spectra captured using Jeol (¹H 400 MHz, ¹³C 100.5 MHz, SIPBS, University of Strathclyde) and Bruker instruments (¹H 600 MHz, ¹³C 150 MHz, Department of Pure and Applied Chemistry, University of Strathclyde) and was confirmed by two-dimensional NMR (2D-NMR) spectra such as HMQC or HSQC, HMBC, COSY and NOESY as well as comparisons with the literature. A pure sample was dissolved in 500 μL of a suitable deuterated solvent and transferred to 5 mm Norell NMR tube (NORELL Inc., Morganton, NC, USA). Samples that were low in quantity were analysed in Shigemi tubes (SHIGEMI Co., LTD., Hachioji City, Japan) with 180 μL of the appropriate deuterated solvent. Dimethyl sulfoxide-d₆, chloroform-d, acetone-d_6, and methanol-d₃ bought from Sigma-Aldrich (USA) were the deuterated solvents used. The spectra were then processed with MestReNova-9.0 (MNova) 2.10 (Mestrelab Research, S.L, Santiago de Compostela, Spain). The optical rotation of the optically active compounds was measured with the digital polarimeter 341 (PerkinElmer Life and Analytical Sciences, Shelton, CT, USA) in which the pure compound was dissolved in in 2 mL of the suitable solvent (chloroform or acetone) to a concentration of 1 mg/mL.