Admin What is a nitrogenous base with two rings?
The purines, adenine and cytosine, are large with two rings, while the pyrimidines, thymine and uracil, are small with one ring.
Which nucleotides have 2 carbon nitrogen rings in their molecular structure?
Adenine and guanine are classified as purines. The primary structure of a purine is two carbon-nitrogen rings.
Which are the purine bases?
The most important biological substituted purines are adenine and guanine, which are the major purine bases found in RNA and DNA. In DNA, guanine and adenine base pair (see Watson-Crick pairing) with cytosine and thymine (see pyrimidines) respectively.
Where is a double ring structure found?
Note that the purine bases (adenine and guanine) have a double ring structure while the pyrimidine bases (thymine and cytosine) have only a single ring. This was important to Watson and Crick because it helped them figure out how the double helix was formed.
What is the double ring structure?
Pyrimidine bases (single ring structures) are thymine, cytosine and uracil. Purine bases (double ring structures) are adenine and guanine.
What is pyrimidine ring?
The pyrimidine ring is an aromatic heterocycle of two nitrogen and four carbon atoms. The pyrimidine ring has a planar structure, this helps in stacking interactions with purine bases. Pyrimidine pairs with complementary purine bases by hydrogen bonding, for example, thymine with adenine, and cytosine with guanine.
Which drug contain pyrimidine ring?
Pyrimidines
| Drug | Drug Description |
|---|---|
| Idoxuridine | A pyrimidine analog antiviral used for the treatment of viral eye infections, including herpes simplex keratitis. |
| Talbutal | For use as a sedative and hypnotic. |
| Pentobarbital | A barbiturate drug used to induce sleep, cause sedation, and control certain types of seizures. |
What are the 2 purine bases?
Purine bases include adenine (6-aminopurine) and guanine (2-amino-6-oxypurine) (Fig. 6.3).