What mechanism underlies the interaction between enantiomers and chiral receptors?

• A. Type of covalent bonds formed
• B. Three-dimensional arrangement of atoms
• C. Their molecular weight
• D. Size of their molecules

Answer: (B)

The interaction between enantiomers and chiral receptors is fundamentally determined by the three-dimensional arrangement of atoms in the molecules. Enantiomers are stereoisomers that are non-superimposable mirror images of each other, meaning that their spatial orientations are different even though they share the same molecular formula and connectivity.

Chiral receptors, typically found in biological systems, have a specific three-dimensional structure that can interact preferentially with one of the enantiomers over the other. This selectivity arises because the fit between the enantiomer and the receptor is influenced by the arrangement of functional groups and the overall shape of the molecule. If the enantiomer does not match the receptor's configuration precisely, it will not bind effectively, leading to a lack of biological activity or a different response.

Other factors such as the type of covalent bonds, molecular weight, and size can influence interactions to a lesser extent, but they do not account for the specific and selective nature of chiral interactions. The essential aspect here is that the three-dimensional arrangement dictates how these molecules will interact on a molecular level, highlighting the significance of chirality in biochemical processes.