|
Diazinane
Diazinanes, Hexahydrodiazines are a class of nitrogen-containing heterocycles consisting of a saturated four-carbon/two-nitrogen ring. They exist in three isomeric forms depending on the relative position of the two nitrogen atoms, with 1,4-diazinanes being common. Structure The diazinanes have six-membered cyclohexane-like ring but with two carbons replaced by nitrogens. The three isomers of triazinane are distinguished by the positions of their nitrogen atoms, and are referred to as 1,2-diazinane, 1,3-diazinane, and 1,4-diazinane (more commonly called piperazine). References * ''Heterocyclic Chemistry'' T.L. Gilchrist 1985 (1997, ) See also * 6-membered saturated rings with one nitrogen atom: Piperidine * 6-membered saturated rings with two nitrogen atoms: Diazinane ** Piperazine ** Hexahydropyrimidine ** Hexahydropyridazine * 6-membered aromatic rings with two nitrogen atoms: Diazine ** Pyrazine ** pyrimidine ** pyridazine * 6-membered saturated rings with three nitr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocycle
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different chemical element, elements as members of its ring(s). Heterocyclic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of these heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles. 59% of US FDA-approved drugs contain nitrogen heterocycles. Classification The study of heterocyclic chemistry focuses especially on unsaturated derivatives, and the preponderance of work and applications involves unstrained 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of pyridine, thiophene, pyrrole, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocyclic Compounds With 1 Ring
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of these heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles. 59% of US FDA-approved drugs contain nitrogen heterocycles. Classification The study of heterocyclic chemistry focuses especially on unsaturated derivatives, and the preponderance of work and applications involves unstrained 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of pyridine, thiophene, pyrrole, and furan are quinol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperazine
Piperazine () is an organic compound that consists of a six-membered ring containing two nitrogen atoms at opposite positions in the ring. Piperazine exists as small alkaline deliquescent crystals with a saline taste. The piperazines are a broad class of chemical compounds, many with important pharmacological properties, which contain a core piperazine functional group. Origin and naming Piperazines were originally named because of their chemical similarity with piperidine, part of the structure of piperine in the black pepper plant (''Piper nigrum''). The -az- infix added to "piperazine" refers to the extra nitrogen atom, compared to piperidine. It is important to note, however, that piperazines are ''not'' derived from plants in the '' Piper'' genus. Chemistry Piperazine is freely soluble in water and ethylene glycol, but insoluble in diethyl ether. It is a weak base with two pKb of 5.35 and 9.73 at 25 °C.; the pH of a 10% aqueous solution of piperazine is 10.8–11.8. Pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperazine
Piperazine () is an organic compound that consists of a six-membered ring containing two nitrogen atoms at opposite positions in the ring. Piperazine exists as small alkaline deliquescent crystals with a saline taste. The piperazines are a broad class of chemical compounds, many with important pharmacological properties, which contain a core piperazine functional group. Origin and naming Piperazines were originally named because of their chemical similarity with piperidine, part of the structure of piperine in the black pepper plant (''Piper nigrum''). The -az- infix added to "piperazine" refers to the extra nitrogen atom, compared to piperidine. It is important to note, however, that piperazines are ''not'' derived from plants in the '' Piper'' genus. Chemistry Piperazine is freely soluble in water and ethylene glycol, but insoluble in diethyl ether. It is a weak base with two pKb of 5.35 and 9.73 at 25 °C.; the pH of a 10% aqueous solution of piperazine is 10.8–11.8. Pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triazinane
Triazinanes are a class of nitrogen-containing heterocycles. The parent molecules' molecular formula is . They exist in three isomeric forms, 1,3,5-triazinanes being common. The triazinanes have six-membered cyclohexane-like ring but with three carbons replaced by nitrogens. Most commonly, the amines are tertiary. References * ''Heterocyclic Chemistry'' T.L. Gilchrist 1985 (1997, ) See also * 6-membered rings with one nitrogen atom: Piperidine * 6-membered rings with two nitrogen atoms: Diazinane ** Hexahydropyrimidine ** Hexahydropyridazine * Triazine Triazines are a class of nitrogen-containing heterocycles. The parent molecules' molecular formula is . They exist in three isomeric forms, 1,3,5-triazines being common. Structure The triazines have planar six-membered benzene-like ring but ... {{Authority control Heterocyclic compounds with 1 ring Nitrogen heterocycles Six-membered rings Polyamines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrimidine
Pyrimidine (; ) is an aromatic, heterocyclic, organic compound similar to pyridine (). One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring. The other diazines are pyrazine (nitrogen atoms at the 1 and 4 positions) and pyridazine (nitrogen atoms at the 1 and 2 positions). In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U). Occurrence and history The pyrimidine ring system has wide occurrence in nature as substituted and ring fused compounds and derivatives, including the nucleotides cytosine, thymine and uracil, thiamine (vitamin B1) and alloxan. It is also found in many synthetic compounds such as barbiturates and the HIV drug, zidovudine. Although pyrimidine derivatives such as alloxan were known in the early 19th century, a laboratory synthesis of a pyrimidine was not carried out until 1879, when Grimaux reported the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Heterocycles
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N2, a colorless and odorless diatomic gas. N2 forms about 78% of Earth's atmosphere, making it the most abundant uncombined element. Nitrogen occurs in all organisms, primarily in amino acids (and thus proteins), in the nucleic acids ( DNA and RNA) and in the energy transfer molecule adenosine triphosphate. The human body contains about 3% nitrogen by mass, the fourth most abundant element in the body after oxygen, carbon, and hydrogen. The nitrogen cycle describes the movement of the element from the air, into the biosphere and organic compounds, then back into the atmosphere. Many industrially importa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexahydro-1,3,5-triazine
In chemistry, hexahydro-1,3,5-triazine is a class of heterocyclic compounds with the formula (CH2NR)3. They are reduced derivatives of 1,3,5-triazine, which have the formula (CHN)3, a family of aromatic heterocycles. They are often called triazacyclohexanes or TACH's but this acronym is also applied to cis,cis-1,3,5-triaminocyclohexane. Preparation The parent hexahydro-1,3,5-triazine ((CH2NH)3) has been detected as an intermediate in the condensation of formaldehyde and ammonia, a reaction that affords hexamethylene tetraamine. The N-substituted derivatives are more stable. These N,N',N''-trisubstituted hexahydro-1,3,5-triazines arise from the condensation of the amine and formaldehyde as illustrated by the route to 1,3,5-trimethyl-1,3,5-triazacyclohexane: : 3 CH2O + 3 H2NMe → (CH2NMe)3 + 3 H2O The C-substituted derivatives are obtained by reaction of aldehydes and ammonia: :3 RCHO + 3 NH3 → (RCHNH)3 + 3 H2O Known as aldehyde ammonias, these compounds charact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridazine
Pyridazine is an aromatic, heterocyclic, organic compound with the molecular formula . It contains a six-membered ring with two adjacent nitrogen atoms. It is a colorless liquid with a boiling point of 208 °C. It is isomeric with two other diazine () rings, pyrimidine and pyrazine. Occurrence Pyridazines are rare in nature, possibly reflecting the scarcity of naturally occurring hydrazines, common building blocks for the synthesis of these heterocycles. The pyridazine structure is a popular pharmacophore which is found within a number of herbicides such as credazine, pyridafol and pyridate. It is also found within the structure of several drugs such as cefozopran, cadralazine, minaprine, pipofezine, and hydralazine. Synthesis In the course of his classic investigation on the Fischer indole synthesis, Emil Fischer prepared the first pyridazine via the condensation of phenylhydrazine and levulinic acid. The parent heterocycle was first prepared by oxidation of benzocinnol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazine
In organic chemistry, diazines are a group of organic compounds having the molecular formula . Each contains a benzene ring in which two of the C-H fragments have been replaced by isolobal nitrogen. There are three structural isomers: * pyridazine (1,2-diazine) 55px * pyrimidine (1,3-diazine) 45px * pyrazine (1,4-diazine) 50px See also * 6-membered rings with one nitrogen atom: pyridines * 6-membered rings with three nitrogen atoms: triazines * 6-membered rings with four nitrogen atoms: tetrazines * 6-membered rings with five nitrogen atoms: pentazines * 6-membered rings with six nitrogen atoms: hexazine Hexazine (also known as hexaazabenzene) is a hypothetical allotrope of nitrogen composed of 6 nitrogen atoms arranged in a ring-like structure analogous to that of benzene. It would be the final member of the azabenzene (azine) series, in which al ...s References {{Reflist Simple aromatic rings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrazine
Pyrazine is a heterocyclic aromatic organic compound with the chemical formula C4H4N2. It is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. It is a ''"deliquescent crystal or wax-like solid with a pungent, sweet, corn-like, nutty odour"''. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes. Synthesis Many methods exist for the organic synthesis of pyrazine and its derivatives. Some of these are among the oldest synthesis reactions still in use. In the Staedel–Rugheimer pyrazine synthesis (1876), 2-chloroacetophenone is reacted with ammonia to the amino ketone, then condensed and then oxidized to a pyrazine. A variation is the Gutknecht pyrazine synthesis (1879) also based on this selfcondensation, but diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
