What is pyrimidine antagonists?
Pyrimidine antagonists belong to the group of antimetabolite anticancer drugs and show structural resemblance with naturally occurring nucleotides (see Figure 1). Their action is accomplished through incorporation as false precursor in DNA or RNA or through inhibition of proteins involved in nucleotide metabolism.
Is methotrexate a pyrimidine antagonist?
Drugs in the category include methotrexate and 5-fluorouracil (folic acid antagonists); azathioprine, mercaptopurine, and 6-thioguanine (purine antagonists); and cytosine arabinoside and gemcitabine (pyrimidine antagonists).
Is azathioprine a purine antagonist?
Azathioprine (Fig. 26.3) is a purine antagonist that interferes with the production of adenosine and guanine triphosphate, essential components of DNA [64].
What are antimetabolites with example?
Antimetabolites are small, weakly acidic molecules that are cell cycle non-specific, inhibiting cellular metabolism by acting as false substrates during RNA and DNA synthesis. Examples of these agents include methotrexate, 5-fluorouracil, aminopterin, cytarabine, thioguanine, and mercaptopurine.
How do pyrimidine antagonists work?
The pyrimidine antagonists act to block the synthesis of pyrimidine containing nucleotides (C and T in DNA; C and U in RNA). The drugs used to block the construction of these nucleotides have structures that are similar to the natural compound.
Is a pyrimidine?
Pyrimidine is an aromatic heterocyclic organic compound similar to pyridine. In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U).
Does azathioprine lower your immune system?
Azathioprine is a type of medicine called an immunosuppressant. These medicines work by suppressing or “calming” your immune system. This means your immune system becomes weaker. If you take azathioprine for an inflammatory or autoimmune condition, it slows down the production of new cells in your body’s immune system.
How long can you stay on azathioprine?
If tolerated, you will probably be on azathioprine for up to 5 years. Do not stop taking your medicine unless your doctor tells you to, even if you feel well.
What is the purpose of antimetabolite?
Antimetabolites are most commonly used to treat leukemias and cancers of the breast, ovary, and the intestinal tract. But since the drugs work to slow the growth of any quickly dividing cell type, they can be used to treat various others cancers, too.
What are the anthracycline drugs?
Anthracycline chemotherapy medicines are:
- Adriamycin (chemical name: doxorubicin)
- Ellence (chemical name: epirubicin)
- Doxil (chemical name: doxorubicin)
- daunorubicin (brand names: Cerubidine, DaunoXome)
- mitoxantrone (brand name: Novantrone)
What is the mechanism of action of 5-fluorouracil?
5-Fluorouracil (5-FU) can activate p53 by more than one mechanism: incorporation of fluorouridine triphosphate (FUTP) into RNA, incorporation of fluorodeoxyuridine triphosphate (FdUTP) into DNA and inhibition of thymidylate synthase (TS) by fluorodeoxyuridine monophosphate (FdUMP) with resultant DNA damage.
How can you prevent mitosis?
A mitotic inhibitor is a drug that inhibits mitosis, or cell division. These drugs disrupt microtubules, which are structures that pull the chromosomes apart when a cell divides.
What is the definition of a pyrimidine compound?
Pyrimidine Definition. Pyrimidines are simple aromatic compounds composed of carbon and nitrogen atoms in a six-membered ring. The term pyrimidine is also used to refer to pyrimidine derivatives, most notably the three nitrogenous bases that, along with the two purines, are the building blocks of both deoxyribonucleic acid (DNA)…
What are some pyrimidine antagonists used in cancer treatment?
Some pyrimidine antagonists used in cancer therapy are: 1 5-fluorouracil 2 Arabinosylcytosine 3 Capecitabine 4 Gemcitabine 5 Decitabine
How are the atoms in a pyrimidine ring connected?
Pyrimidine Structure Pyrimidine is a simple aromatic ring composed of two nitrogen atoms and four carbon atoms, with hydrogen atoms attached to each carbon. The carbon and nitrogen atoms are connected via alternating double and single bonds. This bond structure allows for resonance, or aromaticity, causing the ring to be very stable.
Which is an analogue of the nucleoside pyrimidine?
Decitabine is a pyrimidine analogue of the nucleoside cytidine [1]. Pyrimidine derivatives Uracil and Thymine are an integral part of RNA and DNA, respectively. UVB light passing through keratinocytes can cause DNA damage by inducing adjacent pyrimidine bases to form pyrimidine dimers [7].