in this video, we're gonna talk about our second group of amino acids, the aromatic amino acids. So the aromatic amino acids all have really big are groups with big benzene rings. And so recall from your previous organic chemistry courses that a benzene ring is just a six member carbon ring. What they conjugated double bond system, just like the one that's shown right here. And also recall from your previous organic chemistry courses that the benzene ring can be shown with a circle in the middle to represent that conjugated double bond system. Now it turns out that there's only three amino acids that are categorized as aromatic, and those are, you know, Alan entire scene and trip to fan and so down below. We have a demonic to help you guys memorize those three aromatic amino acids. And that demonic is just f y w or fat young whippersnappers. And so whippersnappers, believe it or not, is actually a really word. If you google the definition of whippersnappers, you'll see that it's someone that is young, inexperienced and overconfident, and really, these aromatic amino acids Final Alan entire scene and trip to fan act like young, overconfident whippersnappers because they feel like they could go into whatever amino acid group they want. And so not that I expect you guys to know this right now, but you know, Alan in is like I could be categorized into the non polar group tire scenes like I could be categorized into the polar group and trip to fans like I could be categorized into the non polar group or into the polar group. And you'll even see that some textbooks categorized these amino acids in that way. And so they really do act like young whippersnappers that feel like they can go into multiple of these amino acid groups. And so that's why we've categorized them all together as the aromatic amino acids because they had these big benzene rings. And so now that we know that they are indeed young whippersnappers, that they're also fat because they have these big benzene rings. And so hopefully by remembering F Y w or fat young whippersnappers that will help you guys remember the aromatic amino acids of few know Alan entire scene and trip to fan and so down below, we're going to talk about the structures of each of these amino acids, and we're gonna start with F here, which is for Final Alan Ing, and so notice on the far left bloc. Over here, what we have is final Allan E and Fennel al innings three letter amino acid code is phe, and it's one letter. Amino acid code is frenetic with an F and so literally phenylalanine is trying to tell us what it's our group structure is. It's literally telling us that it's Alan in our leader amino acid, with a female group branching off of it. And that's exactly what we have down below. That phenylalanine, or F here, is literally just our leader amino acid aligning with a female group branching off and so recall from your previous organic chemistry courses that a female group is literally just a branching benzene ring. And so when we're drawing phenylalanine structure, we can literally just draw Allen in which we know is a C H three. But we know that the number of hydrogen is gonna change, so it's gonna end up being just too, and then we can draw a branching female group, and so that's just a branching benzene ring. And so that is it that is final. Allen and Structure. It's literally just Allen in our leader amino acid shown here with a female group branching off. So pretty easy, right? So our next aromatic amino acid is Why and why is for tyrosine, which is what we have in our next block Over here and Tyra scenes. Three letter code is T. Y R. And it's one letter code is why phonetically for tyrosine and so tyrosine structure is literally branching directly off of fennel Allen in structure. And so that's exactly what we have down below. That Tyra scene is literally just fino alla nine having a hydroxyl group baby or a hydroxyl baby. And so, if we go back up to our image up above the Onley place, that makes sense for a hydroxyl group, baby. To come out of this benzene ring is from the bottom of the benzene ring. And so it doesn't make sense for our benzene ring. Are hydroxyl group to come off of the sides or come off of the top? Our hydroxyl group baby has to come off of the bottom and so down below when we draw tyrosine structure because we know that it's literally female. Allan e, Weaken draw Fino Allen in Exactly So phenylalanine is literally like this. So that is final outing, and then its final outing Having a hydroxyl group, baby. Which means that the hydroxyl group has to be coming off of the bottom of the benzene ring here. And so it doesn't come off of the sides or anywhere else. It comes off of the bottom. And so, uh, that can hopefully, um, help you guys remember, tire scenes are group because literally, this is tire scenes are group. And so over here on the right, what we have is an image of a baby's head. Coming out upside down on this circular head can help remind you guys of the circular oxygen atom in the hydroxyl group. And so another way to remember tyrosine structure is to recognize that tire seeing kind of sounds like a tire and tires air circular, just like this benzene ring is up here. And so the tyrosine can help remind you guys of the O. H group that is branching off of the tire. And so hopefully that's another way that you can use to remember tire scenes structure. So then. Last but not least, what we have is our last aromatic amino acid of the W. And the W is for trip to fan, which is what we have in our last block over here. And so trip to fans. Three letter code is TR Peak, and it's one letter code is phonetic with a W. Because the way that Bugs Bunny would say it is twit, though fan with a W in it and so down below. What you'll see is that trip to fans structure. The W here is literally just our leader amino acid again Al Inning with two joined rings. The first joint ring is a five member ID ring, and the second joint ring is a six member carbon ring, which is a benzene ring. Now it's important to note that the benzene ring is going to go below. The benzene is below the structure, and because the benzene is below, we're going to draw that benzene ring last. So first we're going to draw our five member ID ring. And so if we start to draw a trip to fan structure, we know that it's literally just our leader. Amino acid Allen in with two joint rings. And so if we draw Allen and we know it's CH three but we know that the number of hydrogen they're gonna change here, it's gonna end up being, too. And then it has to joined rings, Ah, five member Dring and a six member dring. But that six member benzene ring goes below, so we draw it last, which means that we draw the five member drink first. So here is our five member ring. Perfect. So, uh, next What we need to do is realize that our our group in trip to fan structure has a nitrogen Adam in it. And so to figure out where this nitrogen atom actually goes, we can remember that trip to fan trips on a tripod. And we know that tripods have three legs, so that can remind us that there's a three carbon start to this nitrogen atom. And so, looking up above at our our group, uh, notice the our group starts toe begin right here. So are three carbon start would be one carbon right here to carbon right here. And then we've got two different pathways that we could take. We could take this pathway over here, which is our third carbon. And then that would mean that our nitrogen goes right here. So we would have a 123 carbon start and then our nitrogen atom. So that's one possibility. Thea other possibility would have won two carbons and then have our third carbon be over here. And that would mean that our nitrogen would go right here. And so either possibility is possible and it doesn't really matter which one you pick. Now, I'm gonna pick the second possibility here just because of space reasons. So let's get rid of these dots and let's put our nitrogen over here. So now that we know where our nitrogen atom is, the next thing that we need to realize is that, uh there what? There's a three carbon start to our nitrogen, and so we just, uh, identify that. And so the next part that we need to realize is that this nitrogen atom right here is not so. The nitrogen atom is not part of the benzene ring. And so we know that the benzene ring is going to be below our structure and so we know that these rings are joined So that means that the benzene ring has to share aside with this other ring that's here. But if the benzene ring shares aside on this side or on this side of the five member ring, then the benzene ring is going to be up above the structure. But we know that the benzene ring has to be below the structure, which means that the benzene ring has to share side on either this side, this side or this side. But we know that the nitrogen atom cannot be part of the benzene, which means that the benzene cannot go on this side or on this side, because otherwise the nitrogen atom would be part of the bending. So that means that the Onley place that the benzene can go is on this side right here. So then we can draw in our benzene structure here, and that is our benzene. And so you can see now that it is below the structure, it has the lowest point on our structure here. And so, uh, the last the very last part here is going to be toe draw in the double bond, and the double bond does not touch so the double bond does not touch the nitrogen or the benzene ring. And so the double bond goes right at this position here. And then, of course, we can draw in. Our hydrogen is coming off of the nitrogen atom, and that is it for a trip to fan structure. So, um, that essentially concludes our lesson on the aromatic amino acids, and we'll be able to get some practice utilizing all of these memory tools and our next practice problems, so I'll see you guys there.
Draw in the R-groups from memory for each of the aromatic amino acids.