Synthesis, crystal structures, and spectral properties of double N-alkylated dimethine cyanine dyes and their interactions with biomolecules and living cells

Abstract

A series of new doubleN-alkylated dimethine cyanine dyes were synthesized, and their crystal structures and spectral properties, as well as their interaction with biomolecules and living cells, were investigated.

Cyanine Dyes Containing Quinoline Moieties: History, Synthesis, Optical Properties, and Applications

“…As well as monomethine cyanines, dimethine cyanines have been found to be mostly asymmetrical and do not differ much in terms of synthetic methods. Compared with monomethine cyanine dyes, dimethine and other polymethine cyanine dyes are more environmentally friendly to synthesize, avoiding the formation of thiol molecules [15] …”

“…There are some examples of dimethine cyanine dyes 38 – 48 available in the literature in which they are synthesized in ethanol with piperidine (Figure 11). [15, 32, 58–61] Compounds 42 – 45 were synthesized by using a microwave in yields above 90 % in less than 5 min and with absorption maxima in the presence of DNA at 483–499 nm [32] …”

“… Structures of some known dimethine cyanine dyes, synthesized from lepidine and quinaldine [15, 32, 58–61] …”

“… Confocal fluorescence microscopic images of A172 cells incubated with dye 38 at concentration 20 μmol L −1 at 37 °C for 10 min [15] …”

“…The quinoline ring system has been widely used in medicinal and industrial chemistry [15–18] . Quinoline has become an attractive scaffold for the development of new fluorescent reagents owing to its small molecular size and nitrogen's ability to form hydrogen bonds.…”