Carbohydrate Antibiotics

Amino acids and peptides Antibiotics Carbohydrates Cyanides and isothiocyanates Estrogens Glycerides Sapogenins Silicones... 

S. Amann, G. Drager, C. Rupprath, A. Kirschning, and L. Elling, (Chemo)enzymatic synthesis of dTDP-activated 2,6-dideoxysugars as building blocks of polyketide antibiotics, Carbohydr. Res., 335 (2001) 23-32. 

Amino acids, peptides, and proteins Asymmetric synthesis and induction Beta-lactam antibiotics Carbohydrates (chemical aspects) Natural product synthesis New antibiotics... 

Work in our laboratories has demonstrated that free-radicals can be harnessed to provide beneficial products and chemical technologies. This paper highlights some of our recent quests for the Holy Grail of free-radical chemistry and includes the preparation of selenium-containing antibiotics, carbohydrates, antioxidants and anti-inflammatory agents and the development of reagents for use in enantioselective synthesis. 

Celluloses Amines, amino acids, antibiotics, carbohydrates, glycosides, hydrocarbons, inorganic ions, nucleic acids, organic acids, peptides, urea derivatives, vitamins... 

KirKhning A. Bergon P, Wang JJ, Floss HG. Synthesis of 4-ami no-3,4-dideoxy-D-arobino-heptulosonic acid 7-pho hate, the biosynthetic precursor of C N units in ansamycin antibiotics- Carbohydr Res 1994 256 245-256. 

Lactic Acid B cteri. The lactic acid bacteria are ubiquitous in nature from plant surfaces to gastrointestinal tracts of many animals. These gram-positive facultative anaerobes convert carbohydrates (qv) to lactic acid and are used extensively in the food industry, for example, for the production of yogurt, cheese, sour dough bread, etc. The sour aromatic flavor imparted upon fermentation appears to be a desirable food trait. In addition, certain species produce a variety of antibiotics. 

Chapman and Hall Chemical Database Chapman and Hall, Ltd. Dialog Dictiona of Organic Compounds (5th ed.), Dictiona of Organometallic Compounds, Carbohydrates, Mmino Mcids, Peptides, Dictionay of Antibiotics and Eelated Compounds, and Dictionay of Organophosphorus Compounds... 

Experimental procedures have been described in which the desired reactions have been carried out either by whole microbial cells or by enzymes (1—3). These involve carbohydrates (qv) (4,5) steroids (qv), sterols, and bile acids (6—11) nonsteroid cycHc compounds (12) ahcycHc and alkane hydroxylations (13—16) alkaloids (7,17,18) various pharmaceuticals (qv) (19—21), including antibiotics (19—24) and miscellaneous natural products (25—27). Reviews of the microbial oxidation of aUphatic and aromatic hydrocarbons (qv) (28), monoterpenes (29,30), pesticides (qv) (31,32), lignin (qv) (33,34), flavors and fragrances (35), and other organic molecules (8,12,36,37) have been pubflshed (see Enzyp applications, industrial Enzyt s in organic synthesis Elavors AND spices). 

Lincomycin. The liacomycias and celesticetins are a small family of antibiotics that have carbohydrate-type stmctures. Clindamycin, a chemical modification of lincomycin, is clinically superior. Antibiotics ia this family inhibit gram-positive aerobic and anaerobic bacteria by interfering with proteia biosyathesis. 

Application of NMR spectroscopy to heterocyclic chemistry has developed very rapidly during the past 15 years, and the technique is now used almost as routinely as H NMR spectroscopy. There are four main areas of application of interest to the heterocyclic chemist (i) elucidation of structure, where the method can be particularly valuable for complex natural products such as alkaloids and carbohydrate antibiotics (ii) stereochemical studies, especially conformational analysis of saturated heterocyclic systems (iii) the correlation of various theoretical aspects of structure and electronic distribution with chemical shifts, coupling constants and other NMR derived parameters and (iv) the unravelling of biosynthetic pathways to natural products, where, in contrast to related studies with " C-labelled precursors, stepwise degradation of the secondary metabolite is usually unnecessary. 

Oligosaccharides also occur widely as components (via glycosidic bonds) of antibiotics derived from various sources. Figure 7.20 shows the structures of a few representative carbohydrate-containing antibiotics. Some of these antibiotics also show antitumor activity. One of the most important of this type is bleomycin A2, which is used clinically against certain tumors. 

Total syntheses of pyrrole alkaloids, furanoterpenes, macrolide antibiotics, and carbohydrates based on transformations catalyzed by transition metals 99SL1523. 

A low stereoselection is also reported for an Ugi reaction which is the central step in the total synthesis of the antibiotic ( + )-furanomycin80. The carbohydrate-derived intermediate, formed from the following acetal and (+ )-a-methyIbenzylamine, reacts with benzoic acid and tert-butyl isocyanide to deliver the precursor 2 of the antibiotic and its diastcreomer 3 in equal amounts80. 

A batch process is customary for producing antibiotics. Submerged culture is used to propagate fungus with suitable carbohydrate resources. This assumption is based on simplicity in calculations and the normal use of penicillin in die pharmaceutical industry. Assume we... 

Carbohydrate Components of Antibiotics. Part II. Alkaline Degradation of Mycaminose and Synthesis of 3,6-Dideoxy-3-dimethylammo-L-altrose and Derivatives Therefrom, A. B. Foster, J. Lehmann, and M. Stacey, /. Chem. Soc., (1962) 1396-1401. 

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