Unity inova 400 spectrometer

NMR spectra were recorded using a Varian Unity INOVA 400 spectrometer (400 MHz for 1H and 101 MHz for 13C-NMR) (Agilent Technologies, Santa Clara, CA, USA) and Bruker Avance NEO 500 spectrometer system (COSY, HMQC, HMBC, and NOESY) (Bruker, Billerica, MA, USA). High-performance liquid chromatography (HPLC) was performed using a Shimadzu system (Shimadzu Corporation, Kyoto, Japan), which consisted of a LC-20AT pump, SPD-20A UV detector, and CBM-20A system controller. High-resolution electrospray ionization mass spectra (HRESIMS) were obtained using an Agilent 6530 Accurate-Mass Q-TOF LC/MS spectrometer system (Agilent Technologies, Santa Clara, CA, USA). Column chromatography (CC) was performed on silica gel (230–400 mesh, Merck, Germany) and Sephadex LH-20 (25–100 mM mesh, Pharmacia, Sweden) and thin-layer chromatography (TLC) on precoated silica gel 60 F254 (1.05554.0001, Merck, Germany) plates. Spots were visualized by spraying p-anisaldehyde solution.

Reagents and chemicals were obtained commercially and used without further purification. All reactions were monitored by thin layer chromatography (TLC) using Merck precoated 60F₂₄₅ plates, and reaction mixtures were purified by column chromatography using MP Silica 40–63 (60 Å). Mass spectroscopy was performed in electrospray ionization (ESI) positive mode using an Expression CMA spectrometer (Advion Ithaca, NY, USA). ¹H NMR (400 and 500 MHz) and ¹³C NMR (100 and 125 MHz) data were obtained using a Varian Unity INOVA 400 spectrometer or a Varian Unity AS500 spectrometer (Agilent Technologies, Santa Clara, CA, USA). DMSO‑d₆ and CDCl₃ were used as NMR solvents. Chemical shift values were recorded in parts per million (ppm) and coupling constants (J) were recorded in hertz (Hz). The following abbreviations are used: s (singlet), d (doublet), t (triplet), q (quartet), m (multiplet), and brs (broad singlet).

All reagents were obtained commercially and used without further purification. Thin-layer chromatography (TLC) and column chromatography were conducted on Merck precoated 60F245 plates and MP Silica 40–63, 60 Å, respectively. High-resolution (HR) mass spectroscopy data were obtained on an Agilent Accurate Mass Q-TOF (quadruple time-of-flight) liquid chromatography (LC) mass spectrometer (Agilent, Santa Clara, CA, USA) in ESI-positive mode. Nuclear magnetic resonance (NMR) spectra were recorded on a Varian Unity INOVA 400 spectrometer or a Varian Unity AS500 spectrometer (Agilent Technologies, Santa Clara, CA, USA) for ¹H NMR (400 and 500 MHz) and for ¹³C NMR (100 MHz). DMSO-d₆, CD₃OD and CDCl₃ were used as solvents for NMR samples. The coupling constant (J) and chemical shift values were measured in hertz (Hz) and parts per million (ppm), respectively. The abbreviations used in the analysis of ¹H NMR data are follows: s (singlet), brs (broad singlet), d (doublet), dd (doublet of doublets), t (triplet), td (triplet of doublets), q (quartet) and m (multiplet).

Molecular weight and molecular weight distribution (M_w/M_n) of polymers were measured by high temperature gel permeation chromatography (HT-GPC) calibrated by narrow molecular weight distribution polystyrene standards using a Varian PL-220 HTGPC equipped with a triple-detection detectors consisting of a two-angle (15 and 90°) light scattering (LS) detector, a differential refractive-index detector and a four-bridge capillary viscometer at 150 °C with 1,2,4-trichlorobenzene as solvent. The normal temperature GPC was examined on a Waters (2414 refractive index detector) at 40 °C with THF as solvent. ¹H NMR (400 MHz) and ¹³C NMR (400 MHz) spectra of polymers were recorded in a Varian Unity Inova 400 spectrometer in CDCl₃ or DMSO-d₆. Differential scanning calorimetry (DSC) experiments were carried out on PerkinElmer DSC-4000 instrument at 10 °C min⁻¹ over the temperature ranging from −50 to 300 °C for standard measurements. Water contact angles on the polymer films were carried out on DSA100 by the dynamic sessile drop method. Polymer films were prepared by spin coating of 3 to 5% (w/w) solution in dimethyl formamide (DMF) onto glass. The solution was dried off the glass by heating for a few hours, and then a second layer was applied and dried. The water contact angles were measured at 25 °C and the values were the average of at least 6 measurements.

All ¹H NMR spectra were carried out on a Varian UNITY INOVA 400 spectrometer. All samples were submitted to identical standard acquisition parameters and pulse. The sequence used was TNNOESY with mixing time of 0,150 seconds, a sat-delay of 2 sec, and a sat-power of 2 dB (decibels). Spectra were recorded at 300 K with a spectral width of 6000 Hz, a 90° pulse, an acquisition time of 2 s, a relaxation delay of 2 s, and 128 scans. The residual water signal was suppressed by applying a presaturation technique with low power radiofrequency irradiation for 2 s during relaxation. The total acquisition time was of 8 min. Chemical shifts were referred to the TSP single resonance at 0.00 ppm.

NMR spectra were recorded on a Varian Unity INOVA 400 spectrometer (400 MHz for ¹H, 100 MHz for ¹³C). ¹H and ¹³C chemical shifts are referenced to TMS as an internal standard with CDCl₃, or DMSO-d₆ as solvents, and chemical shifts are given in ppm. All compounds were characterized by NMR at 25°C. Mass spectra were obtained by positive and negative ESI-MS using a Micromass Q-TOF hybrid quadrupole/time-of-flight instrument (Micromass UK Ltd.). Absorption spectra were taken on a UV-2700 UV-Vis Shimadzu spectrophotometer.
Solutions in organic solvents were dried with anhydrous sodium sulfate and concentrated in vacuo below 45°C. 2, 3, 4, 6-Tetra-O-acetyl-α-D-galactopyranosyl bromide was purchased from the Sigma Chemical Company. β-Gal (E801A) was purchased from the Promega (Madison, WI, United States), and enzymatic reactions were performed at 37°C in the PBS solution (0.1 M, pH = 7.4). Column chromatography was performed on silica gel (200–300 mesh), and silica gel GF₂₅₄ used for analytical TLC was purchased from the Aldrich Chemical Company. The detection was affected by spraying the plates with 5% ethanolic H₂SO₄ (followed by heating at 110°C for 10 min) or by direct UV illumination of the plate. The purity of the final products was determined by HPLC with ≥95%.