Polycyclic

Polycyclic refers to a chemical compound that consists of more than one cyclic structure. These structures can be fused together or linked via a common atom. Polycyclic compounds are prevalent in various fields, including chemistry, biochemistry, and environmental science.

Chemistry

In chemistry, polycyclic compounds are a significant area of study due to their complex structures and diverse properties. They can be classified into two main types: polycyclic aromatic hydrocarbons (PAHs) and polycyclic non-aromatic hydrocarbons (PNAs).

Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They are also produced when coal, oil, gas, wood, garbage, and tobacco are burned. PAHs generated from these sources can bind to or form small particles in the air.

Polycyclic Non-Aromatic Hydrocarbons

Polycyclic non-aromatic hydrocarbons (PNAs), on the other hand, are a class of organic compounds that consist of fused cycloalkane rings, or rings of atoms that only contain single bonds.

Biochemistry

In biochemistry, polycyclic compounds play a crucial role in the structure and function of many biological molecules. For instance, the steroid hormones, which regulate a wide range of physiological processes, are polycyclic compounds.

Environmental Science

In environmental science, polycyclic compounds, particularly PAHs, are of concern due to their potential toxicity and persistence in the environment. They can be released into the air, water, and soil through both natural processes and human activities.

See Also

• Aromatic hydrocarbon
• Non-aromatic hydrocarbon
• Steroid