The molecular dynamics of benzene-hexa-n-heptanoate (BHA7) have been studied in the isotropic liquid phase by multifield carbon-13 nuclear spin relaxation of a carboxyl carbon labeled compound. The experimental data are analyzed with a dynamical model based on the assumption of three types of motion : a fast internal motion in the aliphatic chains, a slow overall reorientation of the molecule, and an intermediate process connected with the flexibility of the carboxyl group. The first two motions occur clearly on different time scales, whereas the last process is not time scale separated from the global molecular tumbling. Previously reported carbon-13 line shapes in the mesophase and in the slid state of BHA7 were used for verification of the results. Measurements of translational diffusion coefficients in isotropic and ordered phases of BHA6 and BHA7 were performed using ’H pulsed field gradient NMR spin-echo techniques.