Lipophilic sulfophenylcarbocyanine dyes: Synthesis of a new class of fluorescent cell membrane probes

Two lipophilic sulfophenylcarbocyanine dyes, 3 and 4, were synthesized as a new class of fluorescent cell membrane probes. Compared with other commonly used membrane probes, the new dyes have improved fluorescent quantum yield, retention in cell membranes and are easier to use in staining cells.