*4.1. General*

HRESIMS mass spectra were measured with an Agilent 1200 series HPLC–UV system in combination with an ESI-TOF-MS (Maxis, Bruker) (column 2.1 × 50 mm, 1.7 μm, C18 Acquity UPLC BEH (Waters), solvent A: H2O + 0.1% formic acid, solvent B: ACN + 0.1% formic acid, gradient: 5% B for 0.5 min increasing to 100% B in 19.5 min, maintaining 100% B for another 5 min, RF = 0.6 mL min−1, UV detection 200–600 nm). NMR spectra were recorded on a Bruker Avance III 700 MHz spectrometer with a 5 mm TCI cryoprobe (1H 700 MHz, 13C 175 MHz, 15N 71 MHz). Chemical shifts δ were referenced to DMSO-*d*6 ( 1H, δ = 2.50 ppm; 13C, δ = 39.51 ppm). UV spectra were recorded using the Shimadzu UV*vis* spectrophotometer UV-2450. Optical rotation was determined using a PerkinElmer 241 polarimeter. Preparative isolation of the major components was achieved with preparative HPLC-system Gilson PLc 2250 (C18 column-nucleodur-7 μm-125 × 40 mm-RP 100, using Solvent A: H2O, solvent B: acetonitrile, gradient system: 20% B for 0.5 min increasing to 50% B in 30 min, 50% B to 100% B for 20 min, maintaining 100% B for 5 min, flow rate = 50 mL/min, detection at 200–600 nm).
