The photophysical properties and the first observation of UV laser generation of molecules based on 2-phenylbenzothiazole with electron-donating substituents at the 2′ and 4′ positions are reported. The high gain of the amplified spontaneous emission, good efficient laser output, and extreme photostability for this class of laser dyes make their practical application feasible when pumped by the third harmonic (355 nm) of the YAG laser.