Development of new synthetic methodologies for the synthesis of unusual isocoumarin and indole derivatives:The chemistry of homophthalic acid

Özcan, Sevil
Many heterocyclic compounds containing nitrogen, oxygen and sulfur show wide range of physiological activities and their synthesis has always been attracted the interest of chemists. The aim of this research is to develop new synthetic methodologies leading to the synthesis of new derivatives of isocoumarines, indoles, isoquinolines, benzodiazepinones and quinazolines, which have been found to show important biological activities. Starting from homophthalic acid and bishomophthalic acid the corresponding acyl azides were proposed to be synthesized, which then would be used for the synthesis of various heterocycles. The proposed diazide from homophthalic was not formed due to the tendency of the ortho-positioned acid to undergo cyclization. Instead, new unusual benzochromen and isocoumarin derivatives have been synthesized in a single step, for which reasonable mechanisms have been proposed. The half ester produced from homophthalic acid was an important key compound for the synthesis of new highly substituted indole derivatives, which are expected to be biologically active. The diisocyanate derived from was synthesized directly from ortho-bromo xylene was treated with alcohols and hydrazine to produce seven membered rings. Instead of the intramolecular cyclization reaction, they underwent polymerization to form new polymers. Furthermore, new synthetic method for the synthesis of pyrazoles has been developed.


Development of novel asymmetric catalysts for various transformations and investigation of a rearrangement reaciıon
Yazıcıoğlu, Emre Yusuf; Tanyeli, Cihangir; Department of Chemistry (2010)
A new class of pyridine and sulfur containing chiral compounds are synthesized. Camphor sulfonyl chloride is chosen as a valuable chiral starting compound. In our synthetic strategy, sulfonylchloride moiety is first reduced to corresponding thiol compound by using triphenylphosphine and then the resultant thiol will be converted to various alkyl, aryl substituted derivatives. The second part of our strategy includes the pyridine ring construction on the carbonyl side of camphor with the formation of β-hydro...
Chemoenzymatic synthesis of chiral hydroxymethyl cycloalkenols
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...
Tanyeli, Cihangir (Informa UK Limited, 1989-01-01)
Some phenolic biphenyl compounds have been synthesised via the annulation reactions of 4-methoxy-2- pyrone with various active methyl compounds.
Studies on the reaction of acyl phosphonates with aldehydes in the presence of proline
Yalçınkaya, Hatice; Demir, Ayhan Sıtkı; Department of Chemistry (2009)
Acyl phosphonates are interesting precursors for the synthesis of biologically active compounds. In the first part, the acyl phosphonates are synthesized starting from the corresponding acyl chloride. The acyl chlorides are converted into acyl phosphonates by using trialkylphosphites. The reaction of acyl phosphonates with aldehydes in the presence of proline furnished not the suggested aldol products via proline catalyzed aldol reaction but bicyclic products via one pot tricomponent 1,3-dipolar cycloadditi...
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...
Citation Formats
S. Özcan, “Development of new synthetic methodologies for the synthesis of unusual isocoumarin and indole derivatives:The chemistry of homophthalic acid,” Ph.D. - Doctoral Program, Middle East Technical University, 2007.