Now that we've looked at some common ways that organic molecules are represented visually, it is time to talk a bit about how they are named. The topic of nomenclature in organic chemistry is so deep and complex that we could spend weeks discussing all the details. The topic is so complicated that an entire organization largely dedicated to standardizing organic nomenclature was created. This organization is called the International Union of Pure and Applied Chemistry (commonly known as IUPAC).

The IUPAC naming system is based on the idea that the name of a molecule should contain all the information you need to draw the molecule, right there in the name. For example - if one chemist said to another "So yesterday, I was working in the lab and I spilled a bottle of (2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal all over my bench, and boy was I mad about it." Then the other chemist would know, just based on all of the information contained in the name, that her colleague had spilled a bottle of this molecule:

Figure 1. (2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal

In our class, we are going to limit the time we spend on nomenclature. Understanding the naming system that IUPAC came up with is useful, but you'll find that as you move forward into more biochemistry and materials chemistry the naming rules deviate from the IUPAC rules, and for very good reason. To illustrate why biomolecules are often referred to by their common names rather than their IUPAC systematic name, let's look at the molecule in Figure 1 above, (2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal. This molecule is commonly called glucose, a name that is much easier to remember.

In the video below, Professor Dave will explain the basics of naming the simplest of organic molecules, the hydrocarbons. These are molecules that are entirely composed of hydrogen and carbon.