Amx 400 nmr spectrometer

The 1D (¹H, ¹³C, APT and DEPT 135) and 2D (HMBC, COSY and HSQC) NMR spectra were acquired using standard pulse sequences on a Bruker model AMX 400 NMR spectrometer operating at 400 MHz and 100 MHz in ¹H NMR and ¹³C NMR, respectively. Results for the chemical shift (δ) were provided in parts per million units (ppm). J values for coupling constants were provided in Hertz (Hz). The HSQC, HMBC, APT and DEPT pulse sequences followed technical standards. For EI-MS, mass spectroscopy with a Thermo Scientific ISQ single-quadrupole mass spectrometer was used. For ESI-MS, a mass spectrometer from Thermo Scientific with a triple-quadrupole Access MAX system and Xcalibur 2.1 software was used. Sephadex LH-20 and silica gel (E. Merck, 70–230 mesh) column chromatography were used for obtaining pure metabolites. Analytical-grade chemicals were used in isolation and purification. Merck TLC sheets and silica gel G 254 F sheets were used for TLC (E. Merck, Germany). Solvent systems S1, ethyl acetate–methanol–ammonia (95:5:5), and S2, EtAc-MeOH-H₂O (4:1:5, v/v), were utilized for TLC analysis. Dragendorff’s and anisaldehyde/sulfuric acid spray reagents and a UV lamp were used to visualize the TLC plates (at 254 and 365 nm). Papaverine was obtained from Sigma-Aldrich (St. Louis, MO, USA).

NMR spectrum was recorded on Bruker AMX-400 NMR spectrometer or Bruker AVANCE III HD600 600 MHz NMR instrument in deuterated solvent at room temperature. High-resolution mass spectrometry (HRMS) was performed on Bruker Daltonics ULTRAFLEXTREME MALDI-TOF/TOF mass spectrometer. UV-vis absorption and emission measurements were performed on a TU-1901 UV-vis spectrophotometer and a Perkin-Elmer LS 55 luminescence spectrometer, respectively. X-ray diffraction (XRD) measurements were carried out using Bruker D8 Advance TXS XRD with Cu Kα radiation at room temperature. Thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) measurements were conducted on TGA Q5000 V3.13 Build 261 instrument and Netzsch DSC 200 F3 under nitrogen at a heating and cooling rate of 5 °C min⁻¹, respectively. Emission quantum yields (Φ_F's) of BP2TPANs in solvents were estimated by using quinine sulfate (Φ_F = 54% in 0.1 N H₂SO₄) as standard, while solid-state efficiencies were determined using an integrating sphere. The ground-state geometries were optimized using the density functional with B3LYP hybrid functional at the basis set level of 6-31G(d). All calculation were performed using the Gaussian 09 package.

10 mg GSK-4 compound dissolved in 0.5 mL CDCl3 and tested for 1H NMR spectra on an AMX 400 NMR spectrometer from Bruker, Germany. 1H NMR was reported as follows: chemical shift, multiplicity (s = singlet, d = doublet, t = triplet, q = quadruplet, m = multiplet), coupling constant (J values) in Hz and integration. Chemical shifts (δ) were reported with respect to the corresponding solvent residual peak at 7.26 ppm for CDCl3 for 1H NMR.

Microwave-assisted synthesis was performed in a Biotage^® Initiator Microwave Synthesizer (Biotage, Uppsala, Sweden). ¹H- and ¹³C-NMR spectra were recorded on an AMX 400 NMR spectrometer (Bruker, Billerica, MA, USA). Spectra were recorded at room temperature in 5 mm outside diameter (o.d.) tubes. Tetramethylsilane (TMS) was used as internal standard, chemical shifts are expressed in ppm (δ) and J in Hz. For the DEPT sequence, the width of the 90° pulse for ¹³C was 4 μs, and that of the 90° pulse for ¹H was 9.5 μs; the delay 2JC,H −1 was set to 3.5 ms (underlined values). The melting point were carried out on a Stuart Scientific Melting Point SMP1 apparatus (Stuart Scientific, Staffordshire, UK).