A Step by Step Guide to Dropping the Base....or A Step by Step Guide to Drawing the Heterocyclic Aromatic Amine Bases

As I was drawing these out, I had a sudden urge to do this entire post in Pirate Speak. I will refrain from doing this. This post is entirely for the sake of my sanity in trying to memorize the heterocyclic aromatic amine bases (what your DNA is composed of).

We have the pyrimidine bases (Uracil, Cytosine, Thymine) and the purine bases (Adenine, Guanine). 

The way that you remember that the PYrimidine bases are U, C, and T is that you: "CUT PY". Cytosine, Uracil, Thymine, PYrimidine.

So.

PYRIMIDINE BASES:

Here's the first pyrimidine base. First we draw pyrimidine and then add a "U" shape for Uracil, fashioned out of the C=O groups. Give the Nitrogen's their H's and add the double bond to mimic pyrimidine's structure and there's uracil.

Next we have Cytosine. I'm going with: it has an -INE so there needs to be an extra amine in there SOMEWHERE so we replace the top carbonyl from Uracil with the NH2, add the double bonds where appropriate and there you have Cytosine.

Last pyrimidine base: Thymine. All we do, because we're AWESOME and already know the structure for Uracil, is we add a methyl group to uracil. Dat it.

PURINE BASES: 

I struggled for a while with memorizing the structure of purine, let alone its two bases. So, because we're in the animal world, lets think of purine as purrrrrrine. "I always landed on all fours...like a cat"

I'll make this photo slightly larger, to have everyone see that I actually forgot one of the double bonds on sadcat's head and drew it in with paint. But, this is a way to draw purine. Take your cat, let it outside where it can get FIV, FeLV and then HBC all in one day. They'll have to amputate its ears because they'll be giant hematomas, your cat will lose two legs, and his tail. Sad cat will be very sad.

Here's a slightly different way to draw purine if you don't like sad cats.

I supposed this is slightly less ridiculous. Okay. Now we know how to draw purine. Let's draw Adenine and Guanine. 

Take care to notice that I AGAIN forgot to put in a hydrogen. Let's NOT do that on my final exam (WHICH IS ON WEDNESDAY). Here's adenine. Just add the NH2 to purine to make it an additional INE. It'll be happy that way.

By reminds me of Avocado, I really meant reminds me of Guacamole... which is made of avocado..but I figure I would mention why Avocado. That's why. That's how. 

There we have them. Hopefully this isn't so abstract that I'll forget it. 

**Edit** 

In case anyone is wondering WHY....this is why:

Guys, this is what our DNA looks like. I have to be able to regurgitate this onto my final exam. Which is, again.... Too soon, too soon.