Dip 3600

The physicochemical analyses of the isolated natural products were essentially performed as previously described [28 (link)]. Optical rotations were measured on a JASCO digital polarimeter (model DIP-3600, JASCO, Tokyo, Japan). UV spectra were determined on a Spectronic Unicam spectrophotometer (Thermo Scientific, Waltham, MA, USA). IR spectra were determined on a JASCO Fourier transform IR-420 spectrometer (JASCO, Tokyo, Japan). ¹H and ¹³C NMR spectra were run on a Bruker spectrometer (Bruker Corporation, Brussels, Belgium) equipped with 5 mm ¹H and ¹³C probes operating at 500 and 125 MHz, respectively, with Tetramethylsilane (TMS) as internal standard. Silica gel 230–400 mesh (Merck, Bielefeld, Germany) and silica gel 70–230 mesh (Merck) were used for flash and column chromatography while precoated aluminum-backed silica gel 60 F254 sheets were used for TLC. Spots were visualized under UV light (254 and 365 nm) or using MeOH–H₂SO₄ reagent.

The optical rotations were determined with a Jasco DIP-3600 digital polarimeter (Jasco, Tokyo, Japan) using a 10 mm cell. The high-resolution mass spectra were recorded using a Micromass-Q-TOF-MS (Waters, Milford, MA, USA). For the DMSO-d₆, MeOD, CDCl₃, and Acetone-d₆, the ¹H NMR and ¹³C NMR spectra were recorded using Bruker DRX (¹H NMR, 500 MHz and ¹³C NMR, 125 MHz) and Bruker Avance 600 (¹H NMR, 600 MHz, and ¹³C NMR, 150 MHz) spectrometers (Bruker, Rheinstetten, Germany), respectively. X-ray crystallography data were collected with a Rigaku Supernova diffractometer using Cu Kα (λ = 1.54184 Å) radiation. Column chromatography (CC) readings were carried out using silica gel (63–200 μm, Merck, Darmstadt, Germany), and Sephadex LH-20. A TLC analysis was performed using percolated aluminum plates backed with silica gel 60 F₂₅₄ sheets. The TLC plate was visualized under UV light (254 and 365 nm), sprayed with H₂SO₄ (10%), and then heated.