Chapter 3. ELECTRONIC STRUCTURE OF ORGANIC MOLECULES

3.1. CONJUGATION AS STABILIZING FACTOR OF MOLECULES

The most interesting are dienes with conjugated double bonds, i. e. 1,3-dienes where the double and single bonds alternate in the chain. There are many polyunsaturated compounds with conjugated double bonds, which play an important role in nature and biology. For example, β-carotene is a yellow-orange pigment in carrots that involves eleven conjugated double bonds:

Other examples of highly conjugated systems among biologically active compounds are retinol (vitamin A) and retinal, the latter being a substance responsible for vision.