Материалы II студенческой межфакультетсткой конференции первокурсников по биоорганической химии
Barbituric Acid Ahmad Taha, group 9. Scientific adviser is Tishakova Tatyana
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- Бұл бет үшін навигация:
- Thiophene
- TRYPTOPHAN
Barbituric AcidAhmad Taha, group 9. Scientific adviser is Tishakova Tatyana.Barbituric acid or malonylurea is an organic compound based on a pyrimidine heterocyclic skeleton. Barbituric acid is the parent compound of barbiturate drugs, although barbituric acid itself is not pharmacologically active. The compound was discovered by the German chemist Adolf von Baeyer on December 4, 1864, the feast of Saint Barbara (who gave the compound its namesake), by combining urea and malonic acid in a condensation reaction. 
Barbiturates are derivatives of barbituric acid. They can be used as hypnotics, sedatives, anticonvulsants and anesthetics, although they are probably most familiar as 'sleeping pills'. The different properties of the various barbiturates depend upon the side groups attached to the ring. Barbiturates are drugs that act as central nervous system depressants, and can therefore produce a wide spectrum of effects, from mild sedation to total anesthesia. The primary mechanism of action of barbiturates is inhibition of the central nervous system. It causes central nervous system depression. This is brought about by stimulating the inhibitory neurotransmitter system in the brain called the [gamma]-amino butyric acid (GABA) system. Barbiturates that are used in controlling seizures include phenobarbitone. These are found to be effective in partial, complex partial and secondarily generalized seizures. Also have interesting applications in the field of psychology, since they can provide access to levels of consciousness not normally attainable except in dreams or trances. ThiopheneAhmed Mahamud, group 9. Scientific adviser is Tishakova Tatyana.Thiophene, also commonly called thiofuran, is a heterocyclic compound with the formula C4H4S. Consisting of a flat five-membered ring, it is aromatic as indicated by its extensive substitution reactions. Related to thiophene are benzothiophene anddibenzothiophene, containing the thiophene ring fused with one and two benzene rings, respectively. Compounds analogous to thiophene include furan (C4H4O) and pyrrole (C4H4NH). At room temperature, thiophene is a colorless liquid with a mildly pleasant odor reminiscent of benzene, with which thiophene shares some similarities. The high reactivity of thiophene toward sulfonation is the basis for the separation of thiophene from benzene, which are difficult to separate by distillation due to their similar boiling points (4 °C difference at ambient pressure). Like benzene, thiophene forms an azeotrope with ethanol. The molecule is flat; the bond angle at the sulphur is around 93 degrees, the C-C-S angle is around 109, and the other two carbons have a bond angle around 114 degrees. The C-C bonds to the carbons adjacent to the sulphur are about 1.34A, the C-S bond length is around 1.70A, and the other C-C bond is about 1.41A Thiophene is considered aromatic, although theoretical calculations suggest that the degree of aromaticity is less than that of benzene. The "electron pairs" on sulfur are significantly delocalized in the pi electron system. As a consequence of its aromaticity, thiophene does not exhibit the properties seen for conventional thioethers. For example the sulfur atom resists alkylation and oxidation. However, oxidation of a thiophene ring is thought to play a crucial role in the metabolic activation of various thiophene-containing drugs, such as tienilic acid and the investigational anticancer drug OSI-930. In these cases oxidation can occur both at sulfur, giving a thiophene S-oxide, as well as at the 2,3-double bond, giving the thiophene 2,3-epoxide, followed by subsequent NIH shift rearrangement TRYPTOPHANElifra Paidamoyo Muchengwa, group 9. Scientific adviser is Tishakova Tatyana.Tryptophan is an aromatic, hydrophobic, amino acid. Its molecular formula is C11H12N2O2.Tryptophan in the Body: Tryptophan is an essential amino acid, tryptophan is found in many common foods, including meats, seeds, nuts, eggs and dairy products. . It is a common misperception that vegetarians are at risk for insufficient tryptophan intake, but there are several excellent plant sources for this amino acid. Foods that are naturally high in protein, either from plants or animals, typically contain the highest levels of tryptophan per serving. The body uses tryptophan to make proteins, the B-vitamin niacin and the neurotransmitters serotonin and melatonin. However, in order to make niacin and serotonin, it also needs to have sufficient iron, riboflavin and vitamin B6. Only the L-stereoisomer of tryptophan is used by the human body. The D-stereoisomer is much less common in nature, though it does occur, as in the marine venom contryphan. Tryptophan as a Dietary Supplement and Drug: Tryptophan is sold as a prescription drug to treat mood disorders. It is usually used with other medicines. It works to make the mood more stable and reduce extremes in behaviour by restoring the balance of certain natural substances (serotonin, melatonin) in the brain. It has been used to support mood, relaxation, and restful sleep. Tryptophan is also available as a dietary supplement, although its use has not been demonstrated to affect levels of tryptophan in the blood. These effects may be related to the role of tryptophan in the synthesis of serotonin. . If you are taking other medications that may affect serotonin (such as many antidepressants), do not take tryptophan without talking with your doctor first. A very serious (possibly fatal) drug interaction may occur. Your doctor should closely monitor you. Some supplement products have been found to contain possibly harmful impurities/additives. Eating large amounts of foods high in tryptophan, such as turkey, has not been shown to cause drowsiness. This effect typically is associated with eating carbohydrates, which trigger the release of insulin. A metabolite of tryptophan, 5-hydroxytryptophan (5-HTP), may have application in the treatment of depression and epilepsy. While you need tryptophan to live, animal research indicates eating too much of it may be bad for your health. Studies in rats correlate a diet low in tryptophan with an extended lifespan. Research in pigs shows too much tryptophan may lead to organ damage and increased insulin resistance. Although L-tryptophan and its metabolites are available for sale as supplements and prescription medications, the FDA has warned that it is not categorically safe to take and may cause illness. Research into the health risks and benefits of tryptophan is ongoing. жүктеу/скачать 3.18 Mb. Достарыңызбен бөлісу:
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