Green synthesis of fluorescent Schiff bases: chemo-photophysical characterization, X-ray structures, and their bioimaging

Abstract

Fluorescent bioimaging technologies have become powerful tools to observe abnormalities in cells. Commercial biomarkers are available however, there are disadvantages such as high isolation cost, low-temperature storage, photodegradation, and low...

Mitochondria-Targeted Luminescent Organotin(IV) Complexes: Synthesis, Photophysical Characterization, and Live Cell Imaging

“…Some specific biomarkers such as coumarin-, diaminomaleonitrile-, salicylaldehyde-, carbazole-, and glucosamine-, Schiff base derivatives have been described previously. Until now, fluorescent Schiff bases , and main-group metals coordinated with Schiff bases − have been used in cell imaging; however, tracking specific organelles such as mitochondria is scarce.…”

New Schiff base salts as sources of blue and green light in the solid state: the role of the anion and protonation

“…Unexpectedly, it crystallized as an unknown polymorph ( 1a ) in contrast to the structure of this compound reported in the previous work ( 1b ). 47 Both in the current work and in the previous one, the Schiff base was synthesized in a similar way, however, in the previous research it was recrystallized after synthesis from a mixture of methanol and chloroform (v/v 3 : 7), which most likely causes the formation of another polymorph ( 1b ).…”

“…For this reason, repeated attempts at synthesis were made, changing its conditions. As a result of one of the attempts, consisting in increasing the amount of substrates used while maintaining other synthesis conditions unchanged compared to method 1, instead of the expected 4 , the previously known polymorph of N -(4′-methoxybenzylidene)-4-aminobenzoic acid ( 1b ) 47 was obtained. Due to the conformational freedom of the Schiff base molecule, changing the synthesis conditions could result in different polymorphic forms of this compound.…”

“…The primary focus of our research was to explore the relationship between the structural attributes of Schiff bases and their exhibited fluorescent properties. Therefore, a specific Schiff base, known from previous work, 47 N -(4′-methoxybenzylidene)-4-aminobenzoic acid, which does not exhibit fluorescence in the solid state, as well as its five inorganic salts, have been synthesized: 4-carboxy- N -(4′methoxybenzylidene)anilium chloride monohydrate ( 2 ), 4-carboxy- N -(4′methoxybenzylidene)anilium bromide monohydrate ( 3 ), 4-carboxy- N -(4′methoxybenzylidene)anilium nitrate ( 4 ), 4-carboxy- N -(4′methoxybenzylidene)anilium hydrogen sulfate ( 5 ), and 4-carboxy- N -(4′methoxybenzylidene)anilium dihydrogen phosphate ( 6 ). During the course of synthesis, the discovery of an unknown polymorph ( 1a ) of N -(4′-methoxybenzylidene)-4-aminobenzoic acid was made.…”

“…During the course of synthesis, the discovery of an unknown polymorph ( 1a ) of N -(4′-methoxybenzylidene)-4-aminobenzoic acid was made. The known polymorph ( 1b , CSD Refcode: YADXUA) 47 was also obtained, however, applying different synthetic procedure than the reported one. This unexpected finding adds an intriguing dimension to the complexity and diversity inherent in Schiff bases, bolstering the relevance of the present research.…”