Microwave-Assisted Syntheses of Rhodamine, Rhodol, and Fluorescein Derivatives.

Area of Science:

• Organic Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Rhodol, fluorescein, and rhodamine scaffolds are crucial in developing novel fluorescent compounds.
• Spirolactam structures offer unique photophysical properties for sensor applications.
• Electron donor amines can modulate the electronic and optical characteristics of fluorescent dyes.

Purpose of the Study:

• To synthesize a new series of rhodol-, fluorescein-, and rhodamine-based spirolactam compounds.
• To investigate the utility of these compounds as high-affinity adenosine triphosphate (ATP) chemo-sensors.
• To optimize synthesis routes for efficient compound preparation.

Main Methods:

• Redesigned synthesis of the rhodol scaffold using 2-(2,4-dihydroxybenzoyl)benzoic acid.
• Employed thermal and microwave-assisted synthesis techniques for compound preparation.
• Evaluated the synthesized compounds for their efficacy as ATP chemo-sensors.

Main Results:

• Successfully prepared a series of rhodol-, fluorescein-, and rhodamine-based spirolactam compounds.
• Obtained one example rhodol methyl ester in good yields (25-30%).
• Synthesized a set of non-cytotoxic rhodamine-based compounds with yields ranging from 40-78% using thermal and microwave methods.
• Demonstrated high affinity of the synthesized compounds as ATP chemo-sensors.

Conclusions:

• The redesigned synthesis approach is effective for preparing rhodol scaffolds.
• Thermal and microwave-assisted synthesis provide efficient routes to novel spirolactam compounds.
• The developed rhodamine-based compounds are promising candidates for sensitive and selective ATP detection.