In chemistry

Chemistry

Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....

, inherent chirality refers to molecules and complexes whose lack of symmetry does not originate from a classic stereogenic element, but is rather the consequence of the presence of a curvature in a structure that would be devoid of symmetry axes in any bidimensional representation.

The expression "inherently chiral" was first used by Boehmer to describe calixarenes with XXYZ or WXYZ substitution patterns at the upper rim, and has been later extended to fullerenes with a chiral molecular framework, like C76, C78, and C84, non symmetric uranyl-salophen complexes and the protonated Schiff base

Schiff base

A Schiff base, named after Hugo Schiff, is a compound with a functional group that contains a carbon-nitrogen double bond with the nitrogen atom connected to an aryl or alkyl group, not hydrogen....

 of 11-cis-retinal, the chromophore of rhodopsin

Rhodopsin

Rhodopsin, also known as visual purple, is a biological pigment of the retina that is responsible for both the formation of the photoreceptor cells and the first events in the perception of light. Rhodopsins belong to the G-protein coupled receptor family and are extremely sensitive to light,...

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