Development of new synthetic methodologies for aminocyclitols

Ekmekçi, Zeynep
Aminocyclitols are cyclitols in which at least one of the hydroxyl groups is exchanged with an amino functional group. In turn, they constitute a wide group of natural products with interesting biological properties and are widely distributed throughout. In particular, antibiotics containing an aminocyclitol unit have stimulated the development of synthetic methodologies in the search for analogues with enhanced pharmacological profiles. In this study, three different methods were applied to synthesize diaminoconduritol derivative 202. In the first method, 1,2,3,6-tetraphthalic anhydrate (196), derived from Diels-Alder reaction between of maleic anhydride and 3-sulfolene, was used as a starting compound. Starting with the opening of anhydride group with trimethyl silylazide, tetrazolinone derivative 205 instead of bisamino cyclohexane derivative 201 was obtained. v In the second method, we started the synthesis of target compound 202 by the Birch reduction of benzene. Lactame 218 was synthesized as a key compound. Functionalization of lactame 218 was started with the cleavage of bond between nitrogen and carbonyl group in 218. At the end of the method, imidazole derivative 215 was obtained instead of target compound 202. Diaminoconduritol 242 was synthesized successfully by bishydrazide method. In this strategy, 1,2,3,6-tetraphthalic anhydrate (196) was used as a starting material. After conversion of bisurethane 223 to acylazide derivative 230, Curtius degradation and phtooxygenation reactions were used to introduce the amine and oxygen functionalities into the cyclohexene ring.


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Şenocak, Deniz; Demir, Ayhan Sıtkı; Department of Chemistry (2004)
Chiral cyclic alkenols with hydroxymethyl functionality are important structural units in many biologically active natural compouds such as prostaglandins, sesquiterpene antiviral agents, pentenomycins, xanthocidin, sarkomycin, etc. 1,3-cycloalkanediones are converted into bicyclic polyoxo derivatives with formaldehyde and trioxane in the presence of Lewis acid. Selective oxidation of the bicyclic compounds by using manganese(III)acetate followed by enzyme-catalyzed kinetic resolution afforded chiral bicycl...
Enantioselective Michael Addition of Nitroalkanes to Nitroalkenes Catalyzed by Chiral Bifunctional Quinine-Based Squaramides
Kanberoğlu, Esra; Tanyeli, Cihangir (Wiley, 2015-10-26)
A family of chiral bifunctional acid-/base-type quinine/squaramide organocatalysts is shown to be highly active promoters of the conjugate addition of 1-nitropropane to various trans-β-nitroalkenes. The cooperation of the quinine and the sterically encumbered squaramide moieties catalyzed the Michael addition reactions at 0 °C by using a catalyst loading of only 2 mol % to afford the 1,3-dinitro Michael adducts with excellent enantioselectivity and diastereoselectivity (up to 95 % ee and syn/anti isomers
DEMIR, AS; Tanyeli, Cihangir; URKMEZKARAASLAN, R; SAYRAC, T (Informa UK Limited, 1991-01-01)
Short simple synthesis of alkenoic acid esters and their intramolecular cyclization products, 2H-Pyran-2-ones from enolates of carbonyl compounds and enaminoesters are described.
Synthesis of heterocyclic amine substituted novel 1,4-Aminoalcohols and applications in various asymmetric transformations
Keskin, Eda; Tanyeli, Cihangir; Department of Chemistry (2007)
Aminoalcohols are very important compounds used in various asymmetric transformations as chiral ligands or chiral auxiliaries. In this thesis, four novel heterocyclic amine substituted chiral 1,4-aminoalcohols were synthesized. In the synthetic strategy, amide esters were synthesized from (2S, 3R)-3-methoxycarbonylbicyclo[2.2.1]hept-5-ene-2-carboxylic acid by DCC coupling method. Subsequent reduction of these amide esters lead to target 1,4-aminoalcohols. The activities of these novel chiral 1,4-aminoalcoho...
Novel enantioselective synthesis of both enantiomers of furan-2-yl Amines and amino acids
Demir, Ayhan Sıtkı; Sesemoglu, O; Ulku, D; Arici, C (Wiley, 2003-01-01)
A new enantioselective synthesis of furan-2-yl amines and amino acids is described, in which the key step is the oxazaborolidine-catalyzed enantioselective reduction of O-benzyl (E)- and (Z)-furan-2-yl ketone oximes to the corresponding chiral amines. The chirality of the furan-2-yl amines is fully controlled by the appropriate choice of the geometrical isomer of the O-benzyl oxime. Oxidation of the furan ring furnished amino acids in high yields.
Citation Formats
Z. Ekmekçi, “Development of new synthetic methodologies for aminocyclitols,” Ph.D. - Doctoral Program, Middle East Technical University, 2011.