Keywords: Biconformational double ring flip / Conformation analysis / Decalin / Signal transduction / Synthesis design 2,3,6,7-Tetrasubstituted decalins of relative configuration (2β,3α,4aα,6α,7β,8aα) have been synthesized. If substituents as in 6 are chosen, the equilibrium of the biconformational system 2/3 is shifted towards conformer 2. Conversion into the bis(acetal) 16 resulted in a covalently induced double ring flip 17 Ǟ 18. A chelation-induced double ring flip (21 Ǟ 22) was achieved when 2,2Ј-bipyridyl substituents were attached by ether linkages at the receptor positions 6 and 7 of the decalin system. Effector groups were introduced by