Материалы II студенческой межфакультетсткой конференции первокурсников по биоорганической химии
Dmitriy Mendeleev Priscilla-Mary Adarwah Tetteh, group 2. Scientific adviser is Tishakova Tatyana
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- Бұл бет үшін навигация:
- TETRACYCLINE
- RIBOFLAVIN AND ITS DERIVATIVES
Dmitriy MendeleevPriscilla-Mary Adarwah Tetteh, group 2. Scientific adviser is Tishakova Tatyana.Dmitri Ivanovich Mendeleev 8 February 1834 – 2 February 1907 O.S. 27 January 1834 – 20 January 1907) was a Russian chemist and inventor. He formulated the Periodic Law, created his own version of the periodic table of elements, and used it to correct the properties of some already discovered elements and also to predict the properties of elements yet to be discovered. Though Mendeleev was widely honored by scientific organizations all over Europe, including (in 1882) the Davy Medal from the Royal Society of London (which later also awarded him the Copley Medal in 1905), he resigned from Saint Petersburg University on 17 August 1890. In 1893, he was appointed Director of the Bureau of Weights and Measures. It was in this role that he was directed to formulate new state standards for the production of vodka. Mendeleev also investigated the composition of petroleum, and helped to found the first oil refinery in Russia. He recognized the importance of petroleum as a feedstock for petrochemicals. He is credited with a remark that burning petroleum as a fuel "would be akin to firing up a kitchen stove with bank notes."[10] In 1905, Mendeleev was elected a member of the Royal Swedish Academy of Sciences. The following year the Nobel Committee for Chemistry recommended to the Swedish Academy to award the Nobel Prize in Chemistry for 1906 to Mendeleev for his discovery of the periodic system. The Chemistry Section of the Swedish Academy supported this recommendation. The Academy was then supposed to approve the Committee choice as it has done in almost every case. Unexpectedly, at the full meeting of the Academy, a dissenting member of the Nobel Committee, Peter Klason, proposed the candidacy of Henri Moissan whom he favored. Svante Arrhenius, although not a member of the Nobel Committee for Chemistry, had a great deal of influence in the Academy and also pressed for the rejection of Mendeleev, arguing that the periodic system was too old to acknowledge its discovery in 1906. According to the contemporaries, Arrhenius was motivated by the grudge he held against Mendeleev for his critique of Arrhenius's dissociation theory. After heated arguments, the majority of the Academy voted for Moissan. The attempts to nominate Mendeleev in 1907 were again frustrated by the absolute opposition of Arrhenius.[11] In 1907, Mendeleev died at the age of 72 in Saint Petersburg from influenza. The crater Mendeleev on the Moon, as well as element number 101, the radioactive mendelevium, are named after him. TETRACYCLINEPungame Magano Ndapewa Amadhila, group 2. Scientific adviser is Tishakova Tatyana.Tetracycline is a broad spectrum polypetide antibiotic produced by the Steptomyces genus of Actibacteria, indicated for use against many bacterial infections. It is a protein synthesis inhibitor. It is commonly used to treat acne today and more recently rosacea, and is historically important in reducing the number of deaths from cholera. Tetracycline is marketed under the brand name Sumycin, Tetracyn and Panmycin, among others. Actinide is a thread- like fiber formulation used in dental application. It is also used to produce several semisynthetic derivatives, which together are known as the tetracycline antibiotics. the term tetracycline is also used to denote the four ring system of this compound "tetracycline" are related substances that contain the same four ring system. Tetracycline have a broad spectrum of antibiotic action. Originally they possesed some level of bacteriostatic activity against almost all medically relevant aerobic and anaerobic bacterial general, both Gram positive and negative with a few exceptions such as Pseudomonas aeroginosa and proteus spp, which display intrinsic resistance. Since tetracycline is absorbed into bones, it is used as marker of bone growth for biopsies in humans. Tetracycline labelling is used to determine the amount of bone growth within a certain period of time usually a period of approximately 21 days. Tetracycline is incorporated into mineralizing bone and can be detected by its fluorescence. REFERENCES (1) Klajn. Rafal, chemistry and chemical biology of tetracycline . (2)Kenneth Todal, Antimicrobial Agents in treatment of infectious disease online textbook.
Riboflavin, also called vitamin B2, a yellow, water-soluble organic compound that occurs abundantly in whey (the watery part of milk) and in egg white. An essential nutrient for animals, it can be synthesized by green plants and by most bacteria and fungi. The greenish yellow fluorescence of whey and egg white is caused by the presence of riboflavin, which was isolated in pure form in 1933 and was first synthesized in 1935. It has the following chemical structure: 
Riboflavin functions as part of metabolic systems concerned with the oxidation of carbohydrates and amino acids, the constituents of proteins. Like thiamin (vitamin B1), it is active not in the free form but in more complex compounds known as coenzymes, such as flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), or flavoprotein. Riboflavin is widely distributed in both plants and animals, but its abundance varies considerably. Milk, eggs, leafy vegetables, kidney, and liver are good dietary sources. An adult human needs 1.0 to 1.3 mg (1 mg = 0.001 gram) of the vitamin per day. A dietary lack of riboflavin is characterized by variable symptoms that may include reddening of the lips with cracks at the corners of the mouth (cheilosis); inflammation of the tongue (glossitis); ocular disturbances, such as vascularization of the eyeball with eyestrain and abnormal intolerance of light; and a greasy, scaly inflammation of the skin. Some disagreement persists as to the characteristic syndrome of riboflavin deficiency in humans because it tends to be associated with a deficiency of other vitamins, notably niacin (see pellagra). PENICILLIN жүктеу/скачать 3.18 Mb. Достарыңызбен бөлісу:
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