Autopol 1 polarimeter

All reactions were performed in dry glassware under Ar atmospheres. Analytical thin layer chromatography (TLC) was performed using Merck 60 F₂₅₄ silica gel plates; column chromatography was performed using Merck 60 silica gel (230–400 mesh). Melting points were determined using an Electrothermal IA 9000 series melting point apparatus and are uncorrected. Optical rotations [α]_D were measured on a Rudolph Research Analytical AUTOPOL I polarimeter. Infrared (IR) spectra were recorded using a JASCO FT/IR-4100 spectrometer. ¹H, ¹³C and ³¹P NMR spectra were recorded using a Bruker NMR spectrometer (AVANCE III 500 MHz). High-resolution fast atom bombardment (FAB) mass spectra were recorded using a JEOL JMS-700 mass spectrometer, at the Daegu Center of KBSI, Korea. All commercially available chemicals were used without further purification; solvents were carefully dried and distilled prior to use. The synthesis of U^FL has been reported previously.^4f

All the reagents involved in this research were commercially available and used without further purification unless otherwise noted. Solvents were either employed as purchased or dried before use by standard laboratory procedures. Thin-layer chromatography (TLC) was carried out on 0.25 mm Leyan silica gel plates (60F-254). Column chromatography was performed on silica gel (200-300 mesh) as the stationary phase. ¹H, ¹³C NMR, 2D NMR spectra were performed on Bruker Avance-500 NMR spectrometers. Chemical shifts are reported in ppm with residual solvents or tetramethylsilane (TMS) as the internal standards. The following abbreviations were used for signal multiplicities: s, singlet; d, doublet; dd, doublet of doublet; m, multiplet. Host-guest complexes were prepared by simply mixing the guests and hosts in 1: 1 stoichiometry in the corresponding solvent. Electrospray-ionization high-resolution mass spectrometry (ESI-HRMS) experiments were conducted on an applied Q-EXACTIVE mass spectrometry system. Circular Dichroism (CD) and UV-Vis spectra were recorded on an Applied Photo Physics Chirascan CD spectropolarimeter, using a 1 cm quartz cuvette. Fluorescent spectra were recorded on a spectrofluorometer (Edinburgh FS5), using a 1 cm quartz cuvette. Specific rotations were measured on Rudolph Research Analytical Autopol I Polarimeter (589 nm) in a 1 dm length cell under 25 °C.

Optical rotation was measured on an Autopol I polarimeter (Rudolph Research Analytical, Hackettstown, NJ, USA). The ultraviolet (UV) absorption spectra were measured in MeOH on a METASH UV-8000 spectrophotometer (Shanghai METASH Instruments Co. Ltd., Shanghai, China). The electronic circular dichroism (ECD) was measured on a JASCO J-815 spectropolarimeter (JASCO Co. Tokyo, Japan). The infrared (IR) spectra were recorded using a Bruker Vector 32 spectrometer (Brucker, Karlsruhe, Germany). NMR spectra were recorded in CDCl₃ (ALDRICH, St. Louis, MO, USA) or MeOH-d₄ (ALDRICH, St. Louis, MO, USA) with tetramethylsilane (TMS) as an internal standard, using a Bruker AV III 500 MHz NMR spectrometer. HR-ESIMS data were obtained on an Agilent 6224 TOF LC/MS. Single crystal X-ray crystallography was determined on an Xcalibur Atlas Gemini Ultra diffractometer (Agilent Technologies). Column chromatography (CC) was performed with silica (100–200 and 200–300 mesh, Qingdao Haiyang Chemical Co., Ltd., Qingdao, China).