Lignans bind to sex hormone-binding globulin (SHBG). The lignan with the highest binding affinity is (+/-)-3,4-divanillyltetrahydrofuran. In a double Stobbe condensation--without use of protecting groups--a wide variety of lignans with different substitution pattern in the aromatic and aliphatic part of the molecule was synthesized. These lignans were tested in a SHBG-binding assay which allowed to deduce the following relationship between structure and activity: 1) (+/-)-diastereoisomers are more active than meso compounds 2.) the 4-hydroxy-3-methoxy (guajacyl) substitution pattern in the aromatic part is most effective 3.) the activity increases with the decline in polarity of the aliphatic part of the molecule.