Mat 311a spectrometer

GlcNA homogenous fraction was applied on thin-layer chromatography (TLC) EM silica gel 60 F sheet (0.2 mm). Use CHCl3/CH3OH (9:1) as the developing eluent with rate flow (Rf)=0.2. U.V model UVGL-58 was used to detect the spot. Varian MAT 311A spectrometer was used for yield data of mass spectra.

Chromatographic solvents were purchased from Fisher Scientific, UK, and used without further purification. Optical rotations were measured in methanol on a JASCO DIP-360 digital polarimeter using a 10 cm cell. Ultraviolet spectra were recorded on a Hitachi UV 3200 spectrophotometer in MeOH. Infrared spectra were recorded on a JASCO 302-A spectrophotometer. ESIMS was recorded on a Finnigan LCQ with a Rheos 4000 quaternary pump (Flux Instrument). EIMS were recorded on a Varian MAT 311A spectrometer (70 eV). EIMS was performed on a JEOL HX 110 mass spectrometer. The ¹H and ¹³C NMR spectra were recorded at 600 and 150 MHz, respectively, on a Bruker AMX 600 NMR spectrometer. Chemical shifts are reported in δ (ppm). Column chromatography was carried out on silica gel (70–230 mesh, Merck) and flash silica gel (230–400 mesh, Merck). TLC was performed on Merck precoated silica gel 60 F₂₅₄ aluminum foil, using ceric sulfate spray reagent for visualization. The purity of compounds was investigated by HPLC. The degree of purity of the positive control compound was ≥98%, while that of the isolated compounds was ≥95%. All reagents used were analytical grade.