A triad (Az-SnP-Az) consisting of two azorubine ligands (Az) axially bonded to the sulfo-derivative of Sn(IV)-tetraphenylporphyrin [SnP(OH)2] has been synthesized. The triad structure is optimized by quantum chemical calculations and confirmed by a complex of physicochemical methods. The spectral-luminescent properties of the triad and its components in aqueous media have been studied. The sensitivity of the photophysical characteristics of the triad to the concentration-dependent viscosity of the solution has been studied on a model system (binary solvent glycerol-water). It has been established that the resulting triad has the properties of a molecular rotor and exhibits high sensitivity to local viscosity at the Az and SnP absorption maxima. The ability to tune the wavelength of the radiation, allows configuring the created “molecular rotor” to monitor the local viscosity for each specific case.
