Abstract: Fourteen new compounds were synthesized of whioh twelve are (S)-( + )-α-methylbutyrylphloroglucinols.On the basis of optical rotation data and theoretical analysis, an empirical correlation between optical rotation and absolute configuration of optically active α-methylbutyrylphloroglucinols has been established by means of Brewster's rule of atomic asymmetry. It can be ser-ved as a means of absolute configuration assignment of optically active α- met hylbutyrylphloroglucinols.