Melting points were obtained on a SGW X-4 micro melting point apparatus (INESA Co., Shanghai, China). Optical rotations were measured on a SGW-533 automatic polarimeter (INESA Co., Shanghai, China). The 1D and 2D NMR spectra were measured with a Bruker DRX-600 instrument (Bruker BioS-pin GmbH Company, Rheinstetten, Germany) with TMS as the internal standard. ESIMS data were recorded on an API QSTAR mass spectrometer (Applied Biosystem/MSD Sciex, Concord, Ontario, Canada); HRESIMS were recorded on a Waters Xevo G2-XS QTof mass spectrometer (USA). ECD spectra were recorded on a JASCO J-810 circular dichroism (CD) spectropolarimeter (JASCO Co., Tokyo, Japan). Column chromatography was performed on silica gel 60 (100–200 mesh, Qingdao Marine Chemical Ltd., Qingdao, China), sephadex LH-20 (GE Healthcare, Uppsala, Sweden), and Develosil ODS (50 μm, Nomura Chemical Co. Ltd., Osaka, Japan). The preparation of TLC was performed on HSGF254 plates (Jiangyou silicone Development Co., Ltd., Yantai, China).
Silica gel 60
Manufactured by Qingdao Marine Chemical
Sourced in China
Silica gel 60 is a type of porous, amorphous silica material commonly used as a stationary phase in column chromatography. It is characterized by a high surface area and well-defined pore size distribution, making it suitable for the separation and purification of a wide range of organic and inorganic compounds.
Automatically generated - may contain errors
Lab products found in correlation
Sephadex lh 20, by GE Healthcare (6 mentions)
Lc 6ad pump, by Shimadzu (4 mentions)
343 spectropolarimeter, by PerkinElmer (3 mentions)
Chirascan cd spectrometer, by Applied Photophysics (3 mentions)
Bio tof iiiq mass spectrometer, by Bruker (2 mentions)
Drx 400, by Bruker (2 mentions)
Rid 10a, by Shimadzu (2 mentions)
Perkin elmer 341 polarimeter, by PerkinElmer (2 mentions)
Avance 3 500 mhz spectrometer, by Bruker (2 mentions)
Maxis q tof mass spectrometer, by Bruker (2 mentions)
Sgw x 4 micro melting point apparatus, by INESA (1 mentions)
Sgw 533 automatic polarimeter, by INESA (1 mentions)
Drx 600 instrument, by Bruker (1 mentions)
J 810 circular dichroism spectropolarimeter, by Jasco (1 mentions)
Xevo g2 xs qtof mass spectrometer, by Waters Corporation (1 mentions)
Silica gel 60 f254 plate, by Merck Group (1 mentions)
Drx 400 spectrometer, by Bruker (1 mentions)
Microplate reader, by Tecan (1 mentions)
Ods a column, by Shimadzu (1 mentions)
Avance drx 500, by Bruker (1 mentions)
8 protocols using silica gel 60
1
Structural Characterization of Natural Compounds
2
Synthesis and Characterization of Sialic Acid Conjugates
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
High-resolution mass spectra (HRMS) were obtained with an APEX IV FT_MS (7.0T) spectrometer (Bruker Daltonics, Inc., Billerica, MA, USA) in positive ESI mode. NMR spectra were recorded on a Bruker DRX 400 spectrometer at ambient temperature. 1H-NMR chemical shifts were referenced to the internal standard TMS (δH = 0.00) or the solvent signal (δH = 3.31 for the central line of CD3OD). 13C-NMR chemical shifts were referenced to the solvent signal (δC = 77.00 for the central line of CDCl3, δC = 49.00 for the central line of CD3OD). Reactions were monitored by thin-layer chromatography (TLC) on a pre-coated silica gel 60 F254 plate (layer thickness 0.2 mm; E. Merck, Darmstadt, Germany) and detected by staining with a yellow solution containing Ce(NH4)2(NO3)6 (0.5 g) and (NH4)6Mo7O24. 4H2O (24.0 g) in 6% H2SO4 (500 mL), followed by heating. Flash column chromatography was performed on silica gel 60 (200–300 mesh, Qingdao Marine Chemical Co., Ltd., Qingdao, China).
All chemicals were used as supplied without further purification. The synthesis of compounds2 –8 , 11 –17 , 27 , 31 –33 , and 43 has been reported previously [31 (link),32 (link),38 (link)]. The intermediates 9 and 10 and the novel sialic acid (C-5 or C-9)-pentacyclic triterpene-Neu5Ac2en conjugates 18 –26 , 28 –30 , 34 –42 , and 44 –46 were obtained as follows.
All chemicals were used as supplied without further purification. The synthesis of compounds
3
Analytical Techniques for Spectroscopic Characterization
4
Analytical Techniques for Structural Characterization
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Optical rotations were determined using a Perkin-Elmer 341 polarimeter (PerkinElmer Co., Waltham, MA, USA). Ultraviolet (UV) spectra were taken on an UVmini-1240 spectrometer (Shimadzu Co., Kyoto, Japan) and HRESIMS spectra on an API QSTAR mass spectrometer (Applied Biosystem/MSD Sciex, Concord, ON, Canada). The 1H, 13C, and 2D NMR spectra were recorded on a Bruker Avance-600 or a Bruker DRX-400 instrument using TMS as an internal standard. Column chromatography was performed on silica gel 60 (200–300 mesh, Qingdao Marine Chemical Ltd., Qingdao, China). For Preparative TLC plates (HSGF254, Jiangyou silicone Development Co., Ltd., Yantai, China), Sephadex LH-20 (GE Healthcare, Uppsala, Sweden) and Develosil ODS (50 μm, Nomura Chemical Co. Ltd., Osaka, Japan) were used.
5
Spectroscopic Characterization of Natural Products
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Optical rotations were recorded in MeOH on a Perkin-Elmer 343 spectropolarimeter. UV spectra and ECD spectra were obtained simultaneously on a Chirascan CD spectrometer (Applied Photophysics Ltd., England) using MeOH as solvent. 1H NMR, 13C NMR, and 2D NMR data were recorded on a Bruker Avance III 500 MHz spectrometer with TMS as internal standard. HRESIMS data were recorded on a Bruker maXis Q-TOF spectrometer. Preparative HPLC were carried out with a Shimadzu Shim-packed Pro-ODS column (20 mm × 25 cm) equipped with a Shimadzu LC-6AD pump and a Shimadzu RID-10A refractive index detector. UPLC analysis was performed on an Acquity H-Class UPLC system consisting of a quaternary solvent delivery system, an auto-sampler, and a DAD detector. For column chromatography, silica gel 60 (100–200 mesh, Qingdao Marine Chemical Ltd., Qingdao, People's Republic of China), YMC ODS (75 μm, YMC Co. Ltd., Kyoto, Japan) and Sephadex LH-20 (GE Healthcare, Uppsala, Sweden) were used. Analytical TLC were performed on HSGF254 silica gel plates (0.2 mm, Yantai Jiangyou silica gel Development Co. Ltd., Yantai, China); spots were visualized after spraying with 10% H2SO4 solution followed by heating.
6
Analytical Characterization of Natural Products
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Optical rotations were determined using a Perkin-Elmer 341 polarimeter (PerkinElmer Co., Waltham, MA, USA). Melting points were taken on a SGW X-4 micromelting point apparatus (INESA Physico Optical Instrument Co., Ltd., Shanghai, China) and HRESIMS spectra on an API QSTAR mass spectrometer (Applied Biosystem/MSD Sciex, Concord, ON, Canada). ECD spectra were recorded at 25 °C on a MOS-450/SFM300 spectrophotometer (Bio-logic, Claix, France). The 1H, 13C, and 2D NMR spectra were recorded on a Bruker DRX-400 instrument using TMS as an internal standard. Column chromatography was performed on silica gel 60 (200–300 mesh, Qingdao Marine Chemical Ltd., Qingdao, China). Preparative HPLC was performed on a Waters 1525 Binary HPLC pump and a Waters 2414 refractive index detector using a YMC-Pack ODS-A column (250 mm × 10 mm I.D.; S-5 μm, 12 nm). For Preparative TLC plates (HSGF254, Jiangyou silicone Development Co., Ltd., Yantai, China), Sephadex LH-20 (GE Healthcare, Uppsala, Sweden) and Develosil ODS (50 μm, Nomura Chemical Co. Ltd., Osaka, Japan) were used.
7
Phytochemical Characterization of Natural Compounds
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Optical rotations were measured in MeOH on a Perkin-Elmer 343 spectropolarimeter. UV spectra and CD spectra were obtained simultaneously on a Chirascan CD spectrometer (Applied Photophysics Ltd., England) with MeOH as solvent. 1D NMR, and 2D NMR experiments were performed on a Bruker Avance III 500 MHz spectrometer. HR-ESIMS data were collected on a Bruker maXis Q-TOF mass spectrometer. Preparative and semipreparative HPLC were performed on a Shimadzu LC-6AD pump and a Shimadzu RID-10A refractive index detector with a Shimadzu Shim-packed Pro-ODS column (20 × 250 mm) and a Waters Nova-Pak® HR C-18 column (7.8 × 300 mm). Silica gel 60 (100–200 mesh, Qingdao Marine Chemical Ltd., Qingdao, China), YMC ODS (75 μm, YMC Co. Ltd., Kyoto, Japan) and Sephadex LH-20 (GE Healthcare, Uppsala, Sweden) were used in CC. Analytical TLC was performed on HSGF254 silica gel plates (0.2 mm, Yantai Jiangyou Silica Gel Development Co. Ltd., Yantai, China); spots were visualized by spraying with 10% H2SO4 solution followed by heating.
8
Analytical Methods for Natural Products
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Optical rotations were obtained on a Perkin-Elmer 341 polarimeter with MeOH as solvent. UV and ECD spectra were recorded in MeOH with a Chirascan CD spectrometer (Applied Photophysics LTD., England). 1H NMR, 13C NMR, and 2D NMR spectra were recorded in chloroform-d or methanol-d4 on a Brucker AVIII 500 M instrument for 1H at 500 and for 13C at 125 MHz using the residual solvent peak as reference. High-resolution electrospray ionization mass spectrometry (HRESIMS) was obtained on Bruker maXis Q-TOF mass spectrometer. ESIMS data were obtained on an MDS SCIEX API 2000 LC/MS instrument (SCIEX, Toronto, Canada). HRESIMS data were obtained on a Bruker Bio TOF IIIQ mass spectrometer (Bruker Daltonics, Billerica, MA, U.S.A.). Preparative HPLC was performed with an HPLC system equipped with a Shimadzu LC-6AD pump (Shimadzu, Kyoto, Japan) using a YMC-pack ODS-A column (5 μm, 10 × 250 mm, YMC, Kyoto, Japan). For column chromatography, silica gel 60 (100–200 mesh, Qingdao Marine Chemical Ltd., Qingdao, China) and YMC ODS (75 μm, YMC, Kyoto, Japan) were used. TLC was performed using HSGF254 silica gel plates (Yantai Jiangyou Silica Gel Development Co. Ltd., Yantai, China).
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!