72323-44-5

Upstream product

• 69-72-7 salicylic acid 
• 119-36-8 methyl salicylate 
• 70203-02-0 N'-(2-phenyl-2-ethylidene)-2-hydroxybenzohydrazide 
• 936-02-7 2-Hydroxybenzoylhydrazine 
• 1122-91-4 4-bromo-benzaldehyde 

Relevant academic research and scientific papers

Hydrazide–Hydrazone Small Molecules as AIEgens: Illuminating Mitochondria in Cancer Cells

Aggregation-induced-emission luminogens (AIEgens) have gained considerable attention as interesting tools for several biomedical applications, especially for bioimaging due to their brightness and photostability. Numerous AIEgens have been developed for lighting up the subcellular organelles to understand their forms and functions not only healthy but also unhealthy states, such as in cancer cells. However, there is lack of easily synthesizable, biocompatible small molecules for illuminating mitochondria (powerhouses) inside cells. To address this issue, an easy and short synthesis of new biocompatible hydrazide–hydrazone-based small molecules with remarkable aggregation-induced emission (AIE) properties is described. These small-molecule AIEgens showed hitherto unobserved AIE properties due to dual intramolecular H-bonding confirmed by theoretical calculation, pH- and temperature-dependent fluorescence and X-ray crystallographic studies. Confocal microscopy showed that these AIEgens were internalized into the HeLa cervical cancer cells without showing any cytotoxicity. One of the AIEgens was tagged with a triphenylphosphine (TPP) moiety, which successfully localized in the mitochondria of HeLa cells in a selective way compared to L929 noncancerous fibroblast cells. These unique hydrazide–hydrazone-based biocompatible AIEgens can serve as powerful tools to illuminate multiple subcellular organelles to elucidate their forms and functions in cancer cells for next-generation biomedical applications.

Synthesis and Biological Evaluation of Some Heterocyclic Compounds from Salicylic Acid Hydrazide

Different heterocyclic compounds were prepared starting from 2-hydroxy benzohydrazide; for example, cyclization of hydrazide hydrazone 3 derived from 2-hydroxybenzohydrazide 2 with acetic anhydride or concentrated sulfuric acid gave 1,3,4-oxadiazole derivatives 4–5. On the other hand, direct cyclization of 2-hydroxy benzohydrazide 2 with one carbon cyclizing agent gave a new derivative of 1,3,4-oxadiazole 7, 8, 9, 10, 11. Heating of hydrazide hydrazone 3 with thioglycolic acid in pyridine gave thiazolidinone 12. When 2-hydroxy benzohydrazide 2 reacted with aliphatic carboxylic acids such as formic acid or acetic acid, it gave the corresponding N-formyl or N-acetyl derivatives 6. Subsequent cyclization of 6 using phosphorous pentasulphide in pyridine gave 1,3,4-thiadiazoles 13. Cyclization of 2-hydroxy benzohydrazide with ethyl acetoacetate gives pyrazolone derivative 14. Finally, when an ethanolic solution of acid hydrazide 2 was treated with ammonium thiocyanate in 35% HCl, it gave the thiosemicarbazide 15. Subsequent treatment of 15 with concentrated sulfuric acid or 10% sodium hydroxide gave 5-amino-1,3,4-thiadiazole 16 and 1,2,4-triazole 17, respectively. The structures of all newly isolated compounds were confirmed using1H NMR, IR spectra, and elemental analyses. The antimicrobial activities for all isolated compounds were examined against different microorganisms.