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The early detection of cancer cells and their visualization before and after surgery are essential for successful pre‐ and post‐operative disease management. Although fluorescence imaging is a sensitive and versatile tool that is finding increasing use in clinical applications, there is a lack of tumour‐targeting fluorophores. We report here a family of fluorescent Schiff base organotin dyes (1: Et2N−L‐SnPh2, 2: Et2N−L‐SnBu2, 3: MeO−L‐SnPh2, 4: MeO−L‐SnBu2, 5: HO−L‐SnPh2, and 6: HO−L‐SnBu2, where L=2‐hydroxybenzylidene‐4‐hydroxybenzhydrazine). In addition to one‐photon‐excited fluorescence, efficient two‐photon excitation was demonstrated in compounds 1–4. Two of the compounds (5 and 6), both with hydroxyl substituents, were capable of selective accumulation in HeLa cells, allowing differentiation from normal cells (periodontal ligament cells). Compounds 1 and 3 showed excellent cancer cell staining (HeLa) using two‐photon bioimaging, which is promising for biomedicine applications. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis and characterization of new boron compounds derived from dithiooxamides. The compounds were characterized by NMR (1H and 13C), UV-vis, fluorescence spectroscopy, and high resolution mass spectrometry. The crystal structure of the mononuclear boron compound was determined by single-crystal X-ray diffraction analysis. The photophysical properties of the boron compounds were investigated, and we found moderate fluorescence emission (compound 2 ΦF: 4.07% and compound 4 ΦF: 2.89%). We also observed that the mononuclear complex presented greater stability. Compound 4 showed interesting luminescent properties; in solid state, it exhibited an increase in fluorescence by mechanostimuli by changing to a bright red color, and also in solution, it showed a decrease in fluorescence intensity when oxygen and air were supplied to the solution. [ABSTRACT FROM AUTHOR]

Four secondary diamines with aromatic spacer groups derived from α,α′-dibromo- p-xylene and 4,4′-bis(chloromethyl)-1,1′-biphenyl have been transformed into bis-dithiocarbamate ligands and each combined with dimethyl-, di- n-butyl-, and diphenyltin(IV) dichloride to yield a total of 12 mononuclear diorganotin(IV) bis-dithiocarbamate complexes with six-coordinate metal coordination geometries and either 23- or 27-membered macrocyclic structures. The products were fully characterized by IR and NMR (1H, 13C, 119Sn) spectroscopy and high-resolution ESI+-TOF mass spectrometry. A representative selection of the macrocyclic complexes was further examined by DFT computational studies and the relative binding energies of the cis and trans isomers of the different diorganotin complexes were calculated and compared. Additionally, four possible conformations of the trans isomers were analyzed. With the purpose of examining whether the complexes can be applied to the recognition of anions, five macrocycles were selected based on criteria that allowed the influence of the aromatic spacer group, the N substituent of the dithiocarbamate ligand, and the organic groups attached to the metal center on the recognition properties to be explored. Among the NMe4+X- salts (X- = F-, Cl-, Br-, I-, NO3-, HSO4-, and CH3COO-) examined, the diorganotin complexes were sensitive to fluoride and carboxylate anions. [ABSTRACT FROM AUTHOR]

Five novel organoboron complexes were synthesized in just 15 min via microware irradiation, by one pot multicomponent reactions between diverse aryl aldehydes with benzoylhydrazide, or 4‐nitrobenzoylhidrazine and diphenyl boronic acid, in a 1:1:1 ratio in benzene. The products were characterized by 1H, 13C, 11B NMR, UV, IR, spectroscopy and high‐resolution mass spectrometry (HRMS). The molecular structure was also determined by single‐crystal X‐ray diffraction for two complexes, which showed the tetra‐coordination of the boron atoms giving rise to distorted tetrahedral molecular geometry with a strong intermolecular C‐H···π interactions. In spite of the low quantum yields exhibited by the series in solution, some complexes stained uniformly the silk fibroins emitting enough fluorescence to allow its characterization by confocal microscopy. Boron as chelate center of the five complexes resulted not to be toxic for B16F10 cells, these compounds are appropriate for their used in medical applications. Five novel organoboron complexes were synthesized via microwave irradiation and one pot multicomponent reactions. The products were characterized by 1H, 13C, 11B NMR, UV, IR, and HRMS. Molecular structure was determined by single‐crystal X‐ray diffraction for two complexes, which showed the tetra‐coordination of boron atoms giving rise to distorted tetrahedral molecular geometry. Complexes were used to produce luminescent silk fibroin and were characterized by confocal microscopy. Cell viability assays showed that the compounds are suitable for use in medical applications. [ABSTRACT FROM AUTHOR]