Ftir 8400s spectrophotometer

The surface properties of the CNPs were conducted through FTIR spectroscopy, using Shimadzu FTIR-8400 S spectrophotometer. CNPs were crushed using KBr pellets, then the FTIR spectrum was conducted at a resolution of 1 cm⁻¹ through the range between 4500 and 500 cm⁻¹.

Melting points were determined on a capillary point apparatus (Stuart SMP3) equipped with a digital thermometer. IR spectra (KBr) were recorded on a Shimadzu FT-IR 8400S spectrophotometer. Reactions were monitored using thin layer chromatography (TLC) on 0.2 mm silica gel F254 plates (Merck) utilizing various solvents for elution. The chemical structures of the synthesized compounds were characterized by nuclear magnetic resonance spectra (¹H-NMR, ¹³C-NMR) and determined on a Bruker NMR spectrometer (500 MHz, 125 MHz for ¹H and ¹³C, respectively). ¹³C-NMR spectra are fully decoupled. Chemical shifts were reported in parts per million (ppm) using the deuterated solvent peak or tetramethylsilane as an internal standard. Colorimetric enzyme inhibitory assays were performed in 96-well plates and the absorbance was recorded utilizing a microplate reader (Infinite F50, Tecan, Switzerland).

FTIR spectroscopy analysis was conducted to analyze the surface properties of the BNC. The BNC sample was ground (crushed) with pure potassium bromide, and the mixture was pressed into a small tablet that was subjected to FTIR analysis^{58 (link)}. The Shimadzu FTIR-8400 S spectrophotometer was used to measure the FTIR spectrum in the range of 4500 to 500 cm⁻¹ at a resolution of 1 cm⁻¹.

All the synthetic work was done by procuring available laboratory grade reagents and analytical grade solvents. The solvents and reagents were used as such provided by the manufacturer. TLC was performed to monitor the reactions and to determine the purity of the products. All the reported compounds were purified by column chromatography. The melting points of the synthesized compounds were determined in open capillary method, expressed in  °C. IR spectra of compounds were recorded on Shimadzu FT-IR 8400-S spectrophotometer by KBr pellet technique and are expressed in cm⁻¹. ¹H-NMR and ¹³C-NMR spectra were recorded on Bruker 400 MHz FT-NMR spectrophotometer using DMSO D₆ and CDCl₃ as the solvents and TMS as internal standard (δ ppm). Mass spectra were obtained using LC–MS ACQUITY UPLC mass spectrometer under ES ionization at 70 eV and Time of flight detector. Retention Time (RT) also observed on the same UPLC instrument by maintaining the below mentioned optimized chromatographic condition: Column: C₁₈ 1.7 micron, Flow rate: 0.4 ml/min, Run time: 15 min, Injection volume: 10 µl, Detector: PDA Detector, TOF, Elution: Gradient, Mobile phase: 0.1% FA in water and Acetonitrile, Column temperature: 60 °C.

Melting points were measured using an open capillary on a Buchi melting point apparatus Buchi labortechnik AG, Essen, Germany, and are uncorrected. All the required chemicals used were purchased from Aldrich (Hamburg, Germany). Thin layer chromatography (TLC) was carried out on 5 × 5 plates coated with silica 0.25 cm N-HR/UV₂₅₄ obtained from Merck (Dramstadt, Germany). IR spectra were recorded over a frequency range of 4000–400 cm⁻¹ on a FT-IR 8400S spectrophotometer (Shimadzu, Tokyo, Japan). ¹H-NMR spectra were recorded on a 300 MHz spectrometer (Tehran, Islamic Republic of Iran) using different solvents and TMS as internal reference Chemical shifts are expressed relative to the internal standard on the δ scale in ppm. Elemental analyses (CHN) were determined on an Eur.Vector EA 3000A system (Rome, Italy). Microwave experiments were conducted using a Microwave Synthesis WorkStation (MAS-II, Microwave Chemistry Technology, Shanghai, China)

Melting points were recorded with a Reichert microscope and are uncorrected. ¹H NMR (500 MHz) and ¹³C NMR (125 MHz) were recorded at room temperature in CD₃OD or (CD₃)₂SO, on a Bruker Avance DRX-500 spectrometer. Chemical shifts (δ) are reported in parts per million (ppm) with the solvent signals as reference relative to TMS (δ = 0) as internal standard, while the coupling constants (J values) are given in Hertz (Hz). COSY, ROESY, TOCSY, HSQC and HMBC experiments were recorded with gradient enhancements using sine shape gradient pulses. The IR spectra were recorded with a Shimadzu FT-IR-8400S spectrophotometer. ESI-MS experiments were performed using a Micromass Q-TOF micro instrument (Manchester, UK) with an electrospray source. Column chromatography was run on Merck silica gel 60 (70–230 mesh) and gel permeation on Sephadex LH-20 while TLC was carried out on silica gel GF₂₅₄ pre-coated plates with detection accomplished by spraying with 50% H₂SO₄ followed by heating at 100°C, or by visualizing with an UV lamp at 254 and 365 nm.