Pyrimidine
IUPAC name	pyrimidine
Identifiers
CAS number	[289-95-2]
PubChem	9260
MeSH	pyrimidine
SMILES	C1=CN=CN=C1
Properties
Molecular formula	C4H4N2
Molar mass	80. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to PubChem is a Database of chemical Molecules The system is maintained by the National Center for Biotechnology Information (NCBI a component Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 088
Melting point	20–22 °C
Boiling point	123–124 °C
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Pyrimidine is a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 3 of the six-member ring. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. Benzene, or benzol, is an organic Chemical compound and a known Carcinogen with the molecular formula C 6 H 6 Pyridine is a Chemical compound with the formula C5[[Hydrogen H5]] N. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny ^[1] It is isomeric with two other forms of diazine. This article is about the chemical concept For "isomerism" of atomic nuclei see Nuclear isomer. Diazine refers to a group of Organic compounds having the Molecular formula C4H4N2

Contents 1 Nucleotides 2 Chemical properties 3 Organic synthesis 4 See also 5 References

Nucleotides

Three nucleobases found in nucleic acids (cytosine, thymine, and uracil) are pyrimidine derivatives:

In DNA and RNA, these bases form hydrogen bonds with their complementary purines. Structure The "skeleton" of adenine A nucleic acid is a Macromolecule composed of chains of monomeric Nucleotides In Biochemistry these Molecules carry Genetic information Cytosine is one of the five main bases found in DNA and RNA. It is a Pyrimidine derivative with a Heterocyclic Aromatic ring Thymine is one of the four bases in the Nucleic acid of DNA that make up the letters ATGC Uracil is a common and naturally occurring Pyrimidine derivative Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units A hydrogen bond results from a Dipole-dipole force between an Electronegative atom and a Hydrogen atom bonded to Nitrogen, Oxygen In Molecular biology, complementarity is a property of double-stranded Nucleic acids such as DNA and RNA as well as DNARNA duplexes Purine ( 1) is a heterocyclic Aromatic Organic compound, consisting of a Pyrimidine ring fused to an Imidazole ring Thus the purines adenine (A) and guanine (G) pair up with the pyrimidines thymine (T) and cytosine (C), respectively. Purine ( 1) is a heterocyclic Aromatic Organic compound, consisting of a Pyrimidine ring fused to an Imidazole ring Adenine is a Purine with a variety of roles in Biochemistry including Cellular respiration, in the form of both the energy-rich Adenosine Guanine is one of the five main Nucleobases found in the Nucleic acids DNA and RNA, the others being Adenine, Cytosine,

In RNA, the complement of A is U instead of T and the pairs that form are adenine:uracil and guanine:cytosine. Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units Adenine is a Purine with a variety of roles in Biochemistry including Cellular respiration, in the form of both the energy-rich Adenosine Uracil is a common and naturally occurring Pyrimidine derivative Guanine is one of the five main Nucleobases found in the Nucleic acids DNA and RNA, the others being Adenine, Cytosine, Cytosine is one of the five main bases found in DNA and RNA. It is a Pyrimidine derivative with a Heterocyclic Aromatic ring

These hydrogen bonding modes are for classical Watson-Crick base pairing. In Molecular biology, two Nucleotides on opposite complementary DNA or RNA strands that are connected via Hydrogen bonds are called Other hydrogen bonding modes ("wobble pairings") are available in both DNA and RNA, although the additional 2'-hydroxyl group of RNA expands the configurations through which RNA can form hydrogen bonds. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units

Chemical properties

A pyrimidine has many properties in common with pyridine, as the number of nitrogen atoms in the ring increases the ring pi electrons become less energetic and electrophilic aromatic substitution gets more difficult while nucleophilic aromatic substitution gets easier. Pyridine is a Chemical compound with the formula C5[[Hydrogen H5]] N. In Chemistry, pi bonds ( π bonds) are covalent Chemical bonds where two lobes of one involved electron orbital overlap two lobes Electrophilic aromatic substitution or EAS is an Organic reaction in which an atom usually Hydrogen, appended to an aromatic system is replaced nucleophilic aromatic substitution is a Substitution reaction in Organic chemistry in which the Nucleophile displaces a good Leaving group, An example of the last reaction type is the displacement of the amino group in 2-aminopyrimidine by chlorine^[2] and its reverse. Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. ^[3] Reduction in resonance stabilization of pyrimidines may lead to addition and ring cleavage reactions rather than substitutions. Resonance in Chemistry is a theory used to represent and model certain types of non-classical Molecular structures Resonance is a key component One such manifestation is observed in the Dimroth rearrangement. The Dimroth rearrangement is a Rearrangement reaction taking place with certain 123-triazoles where Endocyclic and Exocyclic Nitrogen

Compared to pyridine, N-alkylation and N-oxidation is more difficult, and pyrimidines are also less basic: The pKa value for protonated pyrimidine is 1. Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. An amine oxide, also known as amine- N -oxide and N -oxide, is a Chemical compound that contains the Functional group R3N+-O&minus In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and 23 compared to 5. 30 for pyridine.

Organic synthesis

Pyrimidines can also be prepared in the laboratory by organic synthesis. Organic synthesis is a special branch of Chemical synthesis and is concerned with the construction of Organic compounds via Organic reactions Organic One method is the classic Biginelli reaction. The Biginelli reaction is a multiple-component Chemical reaction that creates 34-dihydropyrimidin-2(1 H)-ones 4 from Ethyl acetoacetate Many other methods rely on condensation of carbonyls with amines for instance the synthesis of 2-Thio-6-methyluracil from thiourea and ethyl acetoacetate ^[4] or the synthesis of 4-methylpyrimidine with 4,4-dimethoxy-2-butanone and formamide ^[5]. Condensation is the change of the physical state of aggregation (or simply state of matter from gaseous phase into liquid phase In Organic chemistry, a carbonyl group is a Functional group composed of a Carbon Atom double-bonded to an Oxygen Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. Thiourea is an Organic compound of Carbon, Nitrogen, Sulfur and Hydrogen, with the formula C[[Sulfur S]] The Organic compound ethyl acetoacetate ( EAA) is the Ethyl Ester of Acetoacetic acid. Formamide, also known as methanamide is an Amide derived from Formic acid.

A novel method is by reaction of certain amides with carbonitriles under electrophilic activation of the amide with 2-chloro-pyridine and trifluoromethanesulfonic anhydride ^[6]:

See also

• Purine
• Pyrimidine biosynthesis
• Pyrazine, an analog with the nitrogen atoms in positions 1 and 4
• Pyridazine, an analog with the nitrogen atoms in positions 1 and 2
• Simple aromatic rings
• ANRORC mechanism

References

The Journal of the American Chemical Society (usually abbreviated as J A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.

© 2009 citizendia.org; parts available under the terms of GNU Free Documentation License, from http://en.wikipedia.org
Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic