Chemoenzymatic synthesis of chiral hydroxymethyl cycloalkenols

Şenocak, Deniz
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 bicyclic hydroxy ketones. Reduction of carbonyl group and cleavage of the ether functionality furnished the desired chiral cycloalkanols with hydroxymethyl group. This study is a model for the synthesis of these type of compounds.


Chemoenzymatic functionalization of cyclic 1,2-diketones
Biçer, Işıl; Akkaya, Engin Umut; Department of Chemistry (2006)
Chiral hydroxylated cyclopentane derivatives are important structural units in many biologically active compounds and are also important synthons for the asymmetric synthesis of natural products. Synthesis of these types of compounds in optically pure form found increased interest in pharmaceutical chemistry. For this purpose 5-acetoxy-3-methyl-2-methoxy-2-cyclopentene-1-one and 5-acetoxy-3-ethyl-2-methoxy-2-cyclopentene-1-one were acetoxylated using manganese (III) acetate at a’ positions. Enzyme catalyzed...
Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives
Atlı, Selin; Tanyeli, Cihangir; Department of Chemistry (2005)
a,β-Unsaturated cyclic ketones were selectively oxidized on a'- positions using Mn(OAc)3 and Pb(OAc)4, respectively. The resultant racemic a'-acetoxylated substrates were resolved into corresponding enantiomerically enriched a'-hydroxylated and a'-acetoxylated compounds via PLE hydrolysis. a'-Hydroxylated compounds are racemized quickly, so they were acetylated with acetyl chloride and pyridine in situ to give the corresponding a'-acetoxylated compounds. Resultant a'-acetoxy a,β-unsaturated cyclic ketones r...
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...
Synthesis of novel chiral N,N-dialkyl substituted 1,4-amino alcohols and applications in asymmetric transformation reactions
Çakır, Esen; Tanyeli, Cihangir; Department of Chemistry (2007)
Amino alcohols are valuable bioactive substances and frequently used as chiral catalyst in various asymmetric transformation reactions. In the synthetic route, the asymmetric synthesis of novel chiral N,N-dialkyl substituted chiral 1,4-amino alcohols are performed starting with meso-anhydride 38. Quinine-mediated desymmetrization of the anhydride with methanol afforded (2S,3R)-cis-monoester 39 with a high enantiomeric excess (up to 98% ee). Chemoselective amidation of hemiester with various N,N-dialkyl subs...
Novel studies on the chemoenzymatic synthesis of polychlorinated bicyclic systems and the synthesis of C2 and C3 symmetric chiral ligands
Türkmen, Yunus Emre; Tanyeli, Cihangir; Department of Chemistry (2006)
Optically active polychlorinated bicyclic systems are important starting materials for the synthesis of complex target molecules. In the first part of the study, the syntheses of several racemic and meso hexachloronorbornene derivatives were executed successfully, starting from hexachlorocyclopentadiene. The enantio-enriched acetoxymethyl derivative (-)-2 and the hemiester (-)-6 were synthesized in high e.e. values by using several hydrolase type enzymes. The absolute configuration of (-)-2 was determined b...
Citation Formats
D. Şenocak, “Chemoenzymatic synthesis of chiral hydroxymethyl cycloalkenols,” M.S. - Master of Science, Middle East Technical University, 2004.