Nicolet 380 ft ir instrument

Silica gel (60–80, 200–300 mesh, Qingdao Marine Chemical Co., Ltd., Qingdao, China), ODS gel (20–45 µm, Fuji Silysia Chemical Co., Ltd., Greenville, NC, USA), and Sephadex LH-20 (Merck, Kenilworth, NJ, USA) were used for column chromatography. TLC was conducted on precoated Silica gel G plates (Qingdao Marine Chemical Co., Ltd.), and spots were detected by spraying with 5% H₂SO₄ in EtOH followed by heating. Optical rotation was measured on a Rudolph Autopol III polarimeter. UV spectra were performed on a Shimadzu UV-2550 spectrometer (Beckman, Brea, CA, USA). IR absorptions were obtained on a Nicolet 380 FT-IR instrument (Thermo, Waltham, MA, USA) using KBr pellets. 1D and 2D-NMR spectra were recorded on Bruker AV III spectrometer (Bruker, Billerica, MA, USA) (¹H-NMR at 500 MHz and ¹³C NMR at 125 MHz) using TMS as the internal standard. Chem3D Pro 14.0 (PerkinElmer, Waltham, MA, USA) was used for building these 3D models and calculating energy minimizations.

Optical rotation was performed on a Perkin–Elmer 241MC polarimeter (PerkinElmer, Fremont, CA, USA). NMR data were measured using Bruker Avance III 400 and Bruker DRX 600 instruments (Bruker Biospin AG, Fällanden, Germany). All chemical shifts (δ) were given in ppm referenced to TMS and coupling constants (J) given in Hz. HRESIMS were recorded on an Agilent G6520 Q-TOF mass spectrometer. The ECD curves and UV data were collected on a Jasco J-810 spectropolarimeter (JASCO, Tokyo, Japan). IR absorptions were obtained on a Nicolet 380 FT-IR instrument (Thermo, Waltham, MA, USA) using KBr pellets. HPLC was carried out using an Agilent 1260 series liquid chromatography (Agilent Technology Co., Ltd., Santa Clara, CA, USA) equipped with a DAD G1315D detector and an Agilent Eclipse XDB-C₁₈ column (5 µm, 9.4 × 250 mm). Column chromatography was performed on a Sephadex LH-20 (Merck, Darmstadt, Germany) and silica gel (200–300 and 300–400 mesh; Qingdao Haiyang Chemical Group Co., Ltd., Qingdao, China).

Thin-layer chromatography (TLC) was performed on silica gel GF254 (Qingdao Haiyang Chemical Co., Ltd, China) and column chromatography was performed with silica gel (60–80, 200–300 mesh, Qingdao Haiyang Chemical Co.). Sephadex LH-20 (Merck, Germany). The ESI-MS spectra were measured with a VG Auto-3000 Spectrometer, Sephadex LH-20 (Merck, Germany) and MS-C18 column (3.5 μm, 4.6 by 150 mm, Waters). Nuclear Magnetic Resonance (NMR) spectra were obtained on a Bruker AV-500 spectrometer with tetramethylsilane (TMS) as an internal standard. Infrared Spectroscopy (IR) spectra were recorded on a Nicolet 380 FT-IR instrument, as KBr pellets (Thermo, Pittsburgh, PA, USA). UV spectra were obtained on a Shimadzu UV-2550 spectrometer (Beckman, Brea, CA, USA).

Optical rotations were measured with a Rudolph Autopol I polarimeter (Rudolph, Hackettstown, NJ, USA). UV spectra were recorded on a Shimadzu UV-2550 spectrometer (Beckman, Kyoto, Japan). ECD spectra were measured on a JASCO J-715 spectrophotometer (JASCO, Tokyo, Japan). IR absorptions were obtained on a Nicolet 380 FT-IR instrument (Thermo, Pittsburgh, PA, USA) using KBr pellets. HRESIMS were determined by an API QSTAR Pulsar mass spectrometer (Bruker, Bremen, Germany) or 6200 series TOF/6500 series (Agilent, Palo Alto, CA, USA). The NMR spectra were recorded on Bruker Avance 500 NMR spectrometers (Bruker, Bremen, Germany), using TMS as an internal standard. HPLC purifications were performed on an analytical reversed-phase column (YMC-packed C₁₈, 250 mm × 10 mm, 5 µm) (YMC, Tokyo, Japan) using a G1311C 1260 Quat Pump VL and detected with a G1315D 1260 DAD VL detector (190–500 nm) (Agilent Technologies 1260 infinity, Palo Alto, CA, USA). Column chromatography was performed with silica gel (60–80, 200–300 mesh, Qingdao Haiyang Chemical Co., Ltd., Qingdao, China), ODS gel (20–45 µm, Fuji Silysia Chemical Co., Ltd., Durham, NC, USA), and Sephadex LH-20 (Merck, Darmstadt, Germany). TLC was carried out on NUSCRIPT silica gel GF254 (Qingdao Haiyang Chemical Co., Ltd., China), and peaks were detected by spraying with 5% H₂SO₄ in EtOH followed by heating.

Optical rotations were measured on an Anton Paar MCP 5100 polarimeter. IR spectra were obtained using a Nicolet 380 FT-IR instrument (Thermo, USA) using KBr pellets. HRESIMS were determined by a Waters Autospec Premier (Waters, USA) mass spectrometer. The NMR spectra were recorded on Bruker Avance 500 NMR spectrometers (Bruker, Germany) with TMS as an internal standard. The high performance liquid chromatography (HPLC) was performed with an analytic reversed-phased column (YMC–packed C₁₈, 250 mm × 10 mm, 5 µm) (YMC, Japan) using a G1311C 1260 Quat Pump VL and detected with a G1315D 1260 DAD VL detector (190–500 nm) (Agilent Technologies 1260 infinity, USA). For column chromatography, silica gel (60–80, 200–300 mesh, Qingdao Haiyang Chemical Co., Ltd, China), ODS gel (20–45 µm, Fuji Silysia Chemical Co., Ltd, USA), and Sephadex LH-20 (Merck, Germany) were used. TLC analysis was performed on precoated silica gel GF254 plates (Qingdao Haiyang Chemical Co., Ltd, China), and spots were visualized by spraying with 5% H₂SO₄ in EtOH followed by heating. Thermo fisher scientific plate reader was used for enzyme inhibition assays.

Solvents were purified and dried by standard procedures before use. Optical rotations were measured using sodium D line on a JASCO-181 digital polarimeter. IR spectra were recorded on Thermo Scientific-Nicolet 380 FT-IR Instrument. ¹H NMR and ¹³C NMR spectra were recorded on Brucker AC-200 spectrometer. Elemental analysis was carried out on a Carlo Erba CHNS-O analyzer. Full experimental details, ¹H and ¹³C NMR spectra, can be found in Supplementary Material available online at http://dx.doi.org/10.1155/2014/767954.