Fluoromax 4 fluorescence spectrometer

Starting materials, reagents and solvents were purchased from commercial sources (J&K, Aldrich and Acros) and used without further purification. Elemental analysis (EA) was performed with a Vario Micro CUBE CHN elemental analyzer (Elementar, Germany). FT-IR spectra were obtained using a Avatar 360 spectrophotometer (Thermo Nicolet, The United States). Nuclear magnetic resonance (NMR) spectra were recorded at 298 K on a 400 MHz superconducting magnet high-field NMR spectrometer (Bruker, The Swiss), with working frequencies of 400 MHz for ¹H, 376 MHz for ¹⁹F. Chemical shifts are reported in ppm relative to the signals corresponding to the residual non-deuterated solvents, with tetramethylsilane (TMS) as the internal standard. Thermogravimetric (TG) analyses were carried out in a nitrogen stream using Thermal analysis equipment (STA 6000) (PerkinElmer, The United States) with a heating rate of 10 °C/min. Powder X-ray diffraction (PXRD) data were collected in reflection mode at room temperature on a Smart Lab diffractometer (Rigaku, Japan) with a mixture of Cu-Kα1 (λ = 1.54056 Å) and Cu-Kα2 (λ = 1.5418 Å) radiation. Fluorescence spectra were measured on a FluoroMax-4 fluorescence spectrometer (HORIBA Jobin Yvon, France) at room temperature.

Melting points of synthesized compounds were determined under an XT-4 binocular microscope (Beijing Tech Instrument Co., China) and were not corrected. The IR were recorded from KBr disks using a Bruker VECTOR 22 spectrometer (Bruker, USA). NMR spectra were obtained on a JEOL-ECX500 NMR spectrometer (JEOL, Japan) at room temperature using tetramethylsilane as an internal standard. Reaction was monitored by thin-layer chromatography (TLC) on silica gel GF₂₄₅ (400 mesh). Mass spectral studies were performed on a quadrupole/electrostatic field orbitrap mass spectrometer (Thermo Scientific, USA). The micro thermophoresis of the compound and TMV CP was determined by a micro thermophoresis instrument (NanoTemper Tchnologies GmbH, Germany); the fluorescence spectroscopy of the compound interacting with TMV CP was determined by FluoroMax-4 fluorescence spectrometer (HORIBA Scientific, France). All reagents and reactants were purchased from commercial suppliers and were analytical grade or chemically pure. The synthetic route to penta-1,4-diene-3-one oxime ether derivatives containing a quinazolin-4(3H)-one scaffold was shown in Scheme 1. Intermediates 2 and 7 were prepared according to the reported methods [16 , 31 (link)].Scheme 1

Synthetic route to title compounds 8a–8p

The morphology and microstructure of CDs were characterized using FEI Technai G2 F20 transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) was performed using a Thermo (EscaLab 250Xi) X-ray photoelectron spectrometer. Fourier transform infrared (FTIR) spectra were recorded by a Nicolet 5700 FTIR spectrometer with solid KBr pellets. UV–visible absorption spectra were recorded using a Shimadzu UV-2700 UV–visible spectrophotometer. The fluorescence spectra were obtained using a Horiba Fluoro Max-4 fluorescence spectrometer. Fluorescence decay spectra were measured with an FLS 980 (Edinburgh Instruments). The fluorescence images of cells were captured by an Olympus IX-73 fluorescence microscope. The cell viability was detected with a microplate spectrophotometer (Bio Tek, Epoch).