Results of investigation of spectral-luminescent and lasing characteristics of substituted 1,3-oxazoles and 1,3,4-oxadiazoles lasing in the blue-green spectral region are presented. For some compounds, efficiencies of 40 and 38% have been achieved with pump power density of 7 MW/cm2. A 34 nm wide tuning range in the blue-green spectral region with lasing line width of 0.012 nm is shown. A series of laser-active compounds with good solubility in methyl methacrylate capable of effectively lasing is determined