Depolarized dynamic light scattering ͑DLS͒, dielectric relaxation ͑DS͒, and deuterium NMR studies of fragile van der Waals glass forming liquids phenylphthalein-dimethylether ͑PDE͒ and cresolphthalein-dimethylether ͑KDE͒ are presented. In PDE a new dielectric loss process was found, which can be attributed to the 180°flip of the phenyl rings. The previous finding that the distribution of the structural relaxation times measured for PDE and KDE by DS is substantially narrower than that measured

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... y DLS is explained by partial decoupling of the dynamics of the dipole moment from the structural relaxation of the sample. The dynamics of PDE and KDE is compared with the previous studies of two other structurally similar liquids: 1,1Ј -di͑4-methoxy-5-methylphenyl͒cyclohexane ͑BMMPC͒ and 1,1Ј -bis͑p-methoxyphenyl͒cyclohexane ͑BMPC͒ in order to relate dynamical features with the chemical structure of the material. The evidence for the intramolecular character of the secondary relaxations observed in BMPC and PDE is presented.