The relation between

Aims. We search for evidence of a relation between properties of young stellar objects (YSOs) and their parent molecular clouds to understand the initial conditions of high-mass star formation. Methods. A sample of 135 sources was selected from the InfraRed Astronomical Satellite (IRAS) point source catalog, on the basis of their red color to enhance the possibility of discovering young sources. Using the Kölner Observatorium für SubMillimeter Astronomie (KOSMA) 3-m telescope, a single-point survey in 13CO $J = 2{-}1$ was carried out for the entire sample, and 14 sources were mapped further. Archival mid-infrared (MIR) data were compared with the 13CO emissions to identify evolutionary stages of the sources. A 13CO observed sample was assembled to investigate the correlation between 13CO line width of the clouds and the luminosity of the associated YSOs. Results. We identified 98 sources suitable for star formation analyses for which relevant parameters were calculated. We detected 18 cores from 14 mapped sources, which were identified with eight pre-UC H i