Indazole versus indole-based cationic merocyanines with red shifted in-cellulo emission for selective mitochondria imaging

Recent Advances in N-Heterocyclic Small Molecules for Synthesis and Application in Direct Fluorescence Cell Imaging

“…Additionally, in 2022, Gallavardin and co-workers replaced the classical electron-donating group indole with indazole in merocyanines to study the substitution effect [ 34 ]. The indazole and indole merocyanines 12 and 13 were generally synthesized through a key-step Knoevenagel condensation of ethyl-3,3-dimethyl-3H-indolium iodide 11 with various corresponding aldehydes ( Scheme 10 ).…”

“…( A , D , G , J , M ) Merocyanines 12a – c , 13a , and 13b fluorescence, ( B , E , H ) mitochondria marker MitoTracker™ Green fluorescence, ( K , N ) MitoTracker™ Red fluorescence, ( C , F , I ) merged images of 12a – c with MitoTracker™ Green, and ( L , O ) merged images of 13a or 13b with MitoTracker™ Red. Adapted from [ 34 ].…”

Synthesis of trifluoroethoxy/aryloxy cinnolines, cinnolinones and indazoles from o-alkynylanilines via metal-free diazotization reagent

“…1 They are also employed as intermediates in organic synthesis 2 and exhibit electrochemical, optical and luminescence characteristics. 3 Analogously, heteroatom-substituted cinnolines, such as alkoxy and aryloxy cinnolines, have their own importance (Scheme 1, Part A, i–iv). 4…”

Synthesis and Utilization of 1H-Indazole N-Oxides in the Production of C3-Functionalized 1H-Indazoles

“…1h Recently, fluorescent indazole-based cationic merocyanines were developed and compared with their indole analogues to probe mitochondria (Figure 1 ). 1i 1 H -Indazole drug molecules encompass various examples (Figure 1 ), such as the FDA-approved nonsteroidal drugs Bendazac 2 and Benzydamine, which are used as anti-inflammatories; 3 the 5-HT3-receptor antagonist Granisetron, which is used to prevent nausea; 4 Axitinib 5 and Lonidamine, 6 which are known anticancer agents; the norepinephrine/serotonin reuptake (NSR) inhibitor, which is used to treat fibromyalgia; 7 Gamendazole and Adjudin, which are drug candidates for male contraception; 8 Lificiguat (YC-1), which functions as an activator of guanylyl cyclase, recognized for its outstanding anticancer activity; 9 SAM-531 (Cerlapirdine), which is a highly effective 5-HT6R antagonist, as assessed during clinical trials aimed at treating Alzheimer’s disease; 10 and the 3,5-diaminoindazole derivative, an emergent powerful cyclin-dependent kinase (CDK) inhibitor. 11 1 H -Indazoles also hold significance in coordination chemistry and materials science.…”