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Gloria Rubiales - One of the best experts on this subject based on the ideXlab platform.
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the aza wittig reaction an efficient tool for the construction of carbon nitrogen double bonds
2007Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Domitila Aparicio, Jesus M De Los SantosAbstract:Abstract Recent advances in the aza-Wittig reaction of phosphazene derivatives with several carbonyl compounds are reviewed. Phosphazenes afford inter- and intramolecular aza-Wittig reactions with different compounds such as aldehydes, ketones, esters, thioesters, amides, anhydrides and sulfimides. One of the most important applications of this reaction is the synthesis of a wide range of acyclic and heterocyclic compounds, ranging from simple monocyclic compounds to complex polycyclic and macrocyclic systems.
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reaction of n vinylic Phosphazenes with α β unsaturated aldehydes azatriene mediated synthesis of dihydropyridines and pyridines derived from β amino acids
2006Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Esther Herran, Begona Lecea, Mirari Ayerbe, Fernando P CossioAbstract:Aza-Wittig reaction of N-vinylic Phosphazenes (1,2 addition), derived from diphenylmethylphosphine or derived from trimethylphosphine with alpha,beta-unsaturated aldehydes, leads to the formation of 3-azatrienes through a [2 + 2]-cycloaddition-cycloreversion sequence. The presence of an alkyl substituent in position 3 of N-vinylic Phosphazenes increases the steric interactions, and [4 + 2] periselectivity (1,4 addition) is observed. Reaction of azatrienes with alpha,beta-unsaturated aldehydes yields pyridines.
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mechanism and stereoselectivity of the aza wittig reaction between Phosphazenes and aldehydes
2006Co-Authors: Fernando P Cossio, Concepcion Alonso, Gloria Rubiales, Begona Lecea, Mirari Ayerbe, Francisco PalaciosAbstract:The mechanism of the aza-Wittig reaction between Phosphazenes and aldehydes has been studied computationally, using DFT methods (B3LYP/6-31G* level), and experimentally. It has been found that the reaction consists of a tandem [2+2] cycloaddition−cycloreversion sequence in which π and σ orbitals as well as lone pairs are involved. Both [2+2] processes take place via thermally allowed supra-supra mechanisms. P-trimethyl-λ5-Phosphazenes are predicted to be more reactive than their P-triphenyl analogues. The stereochemical outcome of the whole reaction depends only on the second step, because conformational changes in the intermediate 1,3,2-λ5-oxazaphosphazetidines have a much lower activation energy than the second [2+2] cycloreversion reaction. Preferential or exclusive formation of the corresponding (E)-imines is predicted.
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reactions of n vinylic Phosphazenes with azodicarboxylic and acetylenic esters
2004Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Jose Maria EzpeletaAbstract:N-Vinylic Phosphazenes react as enamines (1,4-addition) with azodicarboxylic esters, whereas different behavior is observed when these Phosphazenes react with dimethyl acetylenedicarboxylate (3,4-addition). A [2+2] cycloaddition reaction of the vinyl moiety of vinylic Phosphazenes with the acetylenic triple bond of the acetylenic esters followed by a ring opening leads to the formation of functionalized conjugated Phosphazenes.
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reaction of acetylenic esters and n functionalized Phosphazenes 1 2 versus 1 4 addition of n vinylic Phosphazenes
2003Co-Authors: Francisco Palacios, Concepcion Alonso, Jaione Pagalday, Ana Ochoa M De Retana, Gloria RubialesAbstract:Reaction of Phosphazenes derived from aminophosphonates with acetylenic esters leads to conjugated phosphorus ylides. The formation of these stabilized ylides is explained through a [2+2] cycloaddition reaction of the PN linkage of the phosphazene (1,2-addition) and the triple bond of the acetylenic ester followed by ring opening of the azaphosphete intermediate. However, in the case of N-vinylic Phosphazenes, the Phosphazenes derived from triphenyl- and trimethyl-phosphine react as enamines (1,4-addition) with diacetylenic esters, whereas in Phosphazenes derived from trimethylphosphine a 1,2-addition of ethyl propiolate to the PN linkage of the phosphazene is produced.
Francisco Palacios - One of the best experts on this subject based on the ideXlab platform.
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the aza wittig reaction an efficient tool for the construction of carbon nitrogen double bonds
2007Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Domitila Aparicio, Jesus M De Los SantosAbstract:Abstract Recent advances in the aza-Wittig reaction of phosphazene derivatives with several carbonyl compounds are reviewed. Phosphazenes afford inter- and intramolecular aza-Wittig reactions with different compounds such as aldehydes, ketones, esters, thioesters, amides, anhydrides and sulfimides. One of the most important applications of this reaction is the synthesis of a wide range of acyclic and heterocyclic compounds, ranging from simple monocyclic compounds to complex polycyclic and macrocyclic systems.
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reaction of n vinylic Phosphazenes with α β unsaturated aldehydes azatriene mediated synthesis of dihydropyridines and pyridines derived from β amino acids
2006Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Esther Herran, Begona Lecea, Mirari Ayerbe, Fernando P CossioAbstract:Aza-Wittig reaction of N-vinylic Phosphazenes (1,2 addition), derived from diphenylmethylphosphine or derived from trimethylphosphine with alpha,beta-unsaturated aldehydes, leads to the formation of 3-azatrienes through a [2 + 2]-cycloaddition-cycloreversion sequence. The presence of an alkyl substituent in position 3 of N-vinylic Phosphazenes increases the steric interactions, and [4 + 2] periselectivity (1,4 addition) is observed. Reaction of azatrienes with alpha,beta-unsaturated aldehydes yields pyridines.
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mechanism and stereoselectivity of the aza wittig reaction between Phosphazenes and aldehydes
2006Co-Authors: Fernando P Cossio, Concepcion Alonso, Gloria Rubiales, Begona Lecea, Mirari Ayerbe, Francisco PalaciosAbstract:The mechanism of the aza-Wittig reaction between Phosphazenes and aldehydes has been studied computationally, using DFT methods (B3LYP/6-31G* level), and experimentally. It has been found that the reaction consists of a tandem [2+2] cycloaddition−cycloreversion sequence in which π and σ orbitals as well as lone pairs are involved. Both [2+2] processes take place via thermally allowed supra-supra mechanisms. P-trimethyl-λ5-Phosphazenes are predicted to be more reactive than their P-triphenyl analogues. The stereochemical outcome of the whole reaction depends only on the second step, because conformational changes in the intermediate 1,3,2-λ5-oxazaphosphazetidines have a much lower activation energy than the second [2+2] cycloreversion reaction. Preferential or exclusive formation of the corresponding (E)-imines is predicted.
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reactions of n vinylic Phosphazenes with azodicarboxylic and acetylenic esters
2004Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Jose Maria EzpeletaAbstract:N-Vinylic Phosphazenes react as enamines (1,4-addition) with azodicarboxylic esters, whereas different behavior is observed when these Phosphazenes react with dimethyl acetylenedicarboxylate (3,4-addition). A [2+2] cycloaddition reaction of the vinyl moiety of vinylic Phosphazenes with the acetylenic triple bond of the acetylenic esters followed by a ring opening leads to the formation of functionalized conjugated Phosphazenes.
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reaction of acetylenic esters and n functionalized Phosphazenes 1 2 versus 1 4 addition of n vinylic Phosphazenes
2003Co-Authors: Francisco Palacios, Concepcion Alonso, Jaione Pagalday, Ana Ochoa M De Retana, Gloria RubialesAbstract:Reaction of Phosphazenes derived from aminophosphonates with acetylenic esters leads to conjugated phosphorus ylides. The formation of these stabilized ylides is explained through a [2+2] cycloaddition reaction of the PN linkage of the phosphazene (1,2-addition) and the triple bond of the acetylenic ester followed by ring opening of the azaphosphete intermediate. However, in the case of N-vinylic Phosphazenes, the Phosphazenes derived from triphenyl- and trimethyl-phosphine react as enamines (1,4-addition) with diacetylenic esters, whereas in Phosphazenes derived from trimethylphosphine a 1,2-addition of ethyl propiolate to the PN linkage of the phosphazene is produced.
Tuncer Hokelek - One of the best experts on this subject based on the ideXlab platform.
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phosphorus nitrogen compounds part 36 syntheses langmuir blodgett thin films and biological activities of spiro bino spiro trimeric Phosphazenes
2016Co-Authors: Nuran Asmafiliz, Zeynel Kilic, Leyla Acik, Betul Aydin, Mustafa Turk, Mehmet Civan, Orhan Avci, Yasemin L Gonder, Tuncer HokelekAbstract:The condensation reactions of hexachlorocyclotriphosphazene (N3P3Cl6, trimer) with the symmetric N2N2 or N2O2 donor type tetradentate bulky ligands (1–4) gave partly substituted spiro-bino-spiro (sbs) (5–8) trimeric Phosphazenes. Compounds 5–8 reacted with pyrrolidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) to give octapyrrolidino- (9–12), morpholino- (13–16) and DASD-substituted cyclotriPhosphazenes (17–20). The structures of the Phosphazenes have been elucidated using FTIR, MS, 1H, 13C{1H} and 31P{1H} NMR, and HSQC spectral data. The molecular and solid-state structures of 5, 6 and 12 were verified by single crystal X-ray diffraction techniques. On the other hand, the ultrathin and highly ordered Langmuir–Blodgett (LB) films of compounds 6, 7, 9 and 12 were also fabricated. The structural characterization of the LB films was made using p-polarized grazing angle (GAIR) and horizontal attenuated total reflectance (HATR) techniques. All the novel phosphazene derivatives were evaluated for antibacterial activities against Gram-positive (G+) and Gram-negative (G−) bacteria and for antifungal activities against yeast strains. In addition, the cytotoxic effects of compounds 9, 13, 15, 16, 19 and 20 were investigated against L929 fibroblast and MDA-MB-231 breast cancer cells. The most active one among these compounds was compound 9 at 6.25 μg mL−1 concentration. The interactions between compounds 5–20 and pBR322 plasmid DNA were determined by agarose gel electrophoresis.
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phosphorus nitrogen compounds part 33 in vitro cytotoxic and antimicrobial activities dna interactions syntheses and structural investigations of new mono 4 nitrobenzyl spirocyclotriPhosphazenes
2016Co-Authors: Aytug Okumus, Zeynel Kilic, Tuncer Hokelek, Leyla Acik, Huseyin Akbas, Yasemin L Koc, Betul Aydin, Mustafa Turk, Hakan DalAbstract:The condensation reactions of hexachlorocyclotriphosphazene, N3P3Cl6, with N-alkyl-N′-mono(4-nitrobenzyl)diamines (1–3), NO2PhCH2NH(CH2) n NHR1 (R1 = CH3 or C2H5), led to the formation of the mono(4-nitrobenzyl)spirocyclotriPhosphazenes (4–6). The tetra-pyrrolidino (4a–6a), piperidino (4b–6b), and 1,4-dioxa-8-azaspiro[4,5]decaPhosphazenes (4c–6c) were prepared from(for) the reactions of partly substituted compounds (4, 5, and 6) with excess pyrrolidine, piperidine, and 1,4-dioxa-8-azaspiro[4,5]decane (DASD), respectively. The partly substituted geminal (4d and 5d) and cis-morpholino (6d) Phosphazenes were isolated from the reactions of excess morpholine in boiling THF and o-xylene, but the expected fully substituted compounds were not obtained. The structures of all the phosphazene derivatives were determined by elemental analyses, MS, FTIR, 1H, 13C{1H}, 31P{1H} NMR, HSQC, and HMBC techniques. The crystal structures of 4, 6, 4a, and 5a were verified by X-ray diffraction analysis. In addition, in vitro cytotoxic activities of fully substituted Phosphazenes (4a–6c) against HeLa cervical cancer cell lines (ATCC CCL-2) and the compounds 4a and 4c against breast cancer cell lines (MDA-MB-231) and L929 fibroblast cells were evaluated, respectively. Apoptosis effect was determined by MDA-MB-231 cancer cell lines and fibroblast cells. The MIC values of the compounds were in the ranges of 9.8–19.5 µM. The compounds 6, 5a, 6a, 5b, and 6d have greater MIC activity against bacterial and yeast strain. The investigation of DNA binding with the Phosphazenes was studied using plasmid DNA. The phosphazene derivatives inhibit the restriction endonuclease cleavage of plasmid DNA by BamHI and HindIII enzymes. BamHI and HindIII digestion results demonstrate that the compounds bind with G/G and A/A nucleotides.
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phosphorus nitrogen compounds part 28 syntheses structural characterizations antimicrobial and cytotoxic activities and dna interactions of new Phosphazenes bearing vanillinato and pendant ferrocenyl groups
2013Co-Authors: Yasemin Tumer, Nuran Asmafiliz, Zeynel Kilic, Tuncer Hokelek, Leyla Acik, Yasemin L Koc, Mehmet Lutfi Yola, Ali Osman Solak, Yagmur OnerAbstract:Abstract The gradually Cl replacement reactions of spirocyclic mono ( 1 and 2 ) and bisferrocenyl cyclotriPhosphazenes ( 3 – 5 ) with the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) gave mono ( 1a – 5a ), geminal ( gem - 1b – 5b ), non-geminal ( cis - 1b , cis - 5b and trans - 2b – 5b ), tri ( 1c – 5c ) and tetra-substituted Phosphazenes ( 1d – 5d ). Some Phosphazenes have stereogenic P-center(s). The chirality of 4c was verified using chiral HPLC column. Electrochemical behaviors were influenced only by the number of ferrocene groups, but not the length of the amine chains and the substituent(s). The structures of the new Phosphazenes were determined by FTIR, MS, 1 H, 13 C and 31 P NMR, HSQC and HMBC spectral data. The solid-state structures of cis - 1b and 4d were examined by single crystal X-ray diffraction techniques. The twelve phosphazene derivatives were screened for antimicrobial activity and the compounds 5a , cis - 1b and 2c exhibited the highest antibacterial activity against G(+) and G(−) bacteria. In addition, it was found that overall gem - 1b inhibited the growth of Mycobacterium tuberculosis . The compounds 1d , 2d and 4d were tested in HeLa cancer cell lines. Among these compounds, 2d had cytotoxic effect on HeLa cell in the first 48 h. Moreover, interactions between compounds 2a , gem - 1b , gem - 2b , cis - 1b , 2c , 3c , 4c , 5c , 1d , 2d and 4d , and pBR322 plasmid DNA were investigated.
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syntheses spectroscopic properties crystal structures biological activities and dna interactions of heterocyclic amine substituted spiro ansa spiro and spiro bino spiro Phosphazenes
2013Co-Authors: Selen Bilge Kocak, Zeynel Kilic, Asli Ozturk, Tuncer Hokelek, Serhat Kocoglu, Aytug Okumus, Yagmur Oner, Leyla AcikAbstract:The heterocyclic amine e. g. pyrrolidine, piperidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) substituted spiro-ansa-spiro (sas) 5a-5d and spiro-bino-spiro (sbs) 6a-6d Phosphazenes were prepared by the replacement reactions of the Cl-atoms in 3 and 4 with heterocyclic amines in dry THF (Scheme 1). All of the phosphazene derivatives were characterized by elemental analysis, FTIR, MS, 1D H-1, C-13 and P-31 NMR and DEPT and 2D HSQC techniques. The crystal structures of fully morpholine substituted sas 5c and sbs 6c Phosphazenes were verified by X-ray diffraction analysis. The relationships between exocyclic OPN bond angles (alpha') and delta P-OPN shifts, and the correlation of Delta(P-N) values and Delta(delta P) or delta P-OPN shifts were presented. The phosphazene derivatives (3, 4, 5a-5d and 6a-6d) were subjected to antimicrobial activity against six pathojen bacteria and two yeast strains. Fully pyrrolidine substituted sbs 6a was found to be quite active against yeast strain Candida tropicalis. In addition, the nature of the interactions of these compounds with pBR322 plasmid DNA was investigated, and the results displayed that partly substituted sas 3 and sbs 4 caused to cleave the DNA. (C) 2013 Elsevier B.V. All rights reserved.
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phosphorus nitrogen compounds 21 syntheses structural investigations biological activities and dna interactions of new n o spirocyclic phosphazene derivatives the nmr behaviors of chiral Phosphazenes with stereogenic centers upon the addition of chir
2010Co-Authors: Muhammet Isiklan, Nuran Asmafiliz, Ezgi Elif Ozalp, Elif Ece Ilter, Zeynel Kilic, Buenyemin Cosut, Serkan Yesilot, Adem Kilic, Asli Ozturk, Tuncer HokelekAbstract:The reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6, with N/O-donor-type N-alkyl (or aryl)-o-hydroxybenzylamines (1a−1e) produce mono- (2a−2e), di- (3a−3d), and tri- (4a and 4b) spirocyclic Phosphazenes. The tetrapyrrolidino monospirocyclic Phosphazenes (2f−2i) are prepared from the reactions of partly substituted compounds (2a−2d) with excess pyrrolidine. The dispirodipyrrolidinoPhosphazenes (3e−3h) and trispiroPhosphazenes (3i−3k) are obtained from the reactions of trans-dispiroPhosphazenes with excess pyrrolidine and sodium (3-amino-1-propanoxide), respectively. Compounds 3a−3d have cis and trans geometric isomers. Only the trans isomers of these compounds are isolated. Compounds 3a−3h have two stereogenic P atoms. They are expected to be in cis (meso) and trans (racemic) geometric isomers. In the trans trispiro compounds (3i−3k), there are three stereogenic P atoms. They are expected to be in racemic mixtures. The stereogenic properties of 3a−3k are confirmed by 31P NMR spectroscopy upon the a...
Leyla Acik - One of the best experts on this subject based on the ideXlab platform.
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phosphorus nitrogen compounds part 36 syntheses langmuir blodgett thin films and biological activities of spiro bino spiro trimeric Phosphazenes
2016Co-Authors: Nuran Asmafiliz, Zeynel Kilic, Leyla Acik, Betul Aydin, Mustafa Turk, Mehmet Civan, Orhan Avci, Yasemin L Gonder, Tuncer HokelekAbstract:The condensation reactions of hexachlorocyclotriphosphazene (N3P3Cl6, trimer) with the symmetric N2N2 or N2O2 donor type tetradentate bulky ligands (1–4) gave partly substituted spiro-bino-spiro (sbs) (5–8) trimeric Phosphazenes. Compounds 5–8 reacted with pyrrolidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) to give octapyrrolidino- (9–12), morpholino- (13–16) and DASD-substituted cyclotriPhosphazenes (17–20). The structures of the Phosphazenes have been elucidated using FTIR, MS, 1H, 13C{1H} and 31P{1H} NMR, and HSQC spectral data. The molecular and solid-state structures of 5, 6 and 12 were verified by single crystal X-ray diffraction techniques. On the other hand, the ultrathin and highly ordered Langmuir–Blodgett (LB) films of compounds 6, 7, 9 and 12 were also fabricated. The structural characterization of the LB films was made using p-polarized grazing angle (GAIR) and horizontal attenuated total reflectance (HATR) techniques. All the novel phosphazene derivatives were evaluated for antibacterial activities against Gram-positive (G+) and Gram-negative (G−) bacteria and for antifungal activities against yeast strains. In addition, the cytotoxic effects of compounds 9, 13, 15, 16, 19 and 20 were investigated against L929 fibroblast and MDA-MB-231 breast cancer cells. The most active one among these compounds was compound 9 at 6.25 μg mL−1 concentration. The interactions between compounds 5–20 and pBR322 plasmid DNA were determined by agarose gel electrophoresis.
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phosphorus nitrogen compounds part 33 in vitro cytotoxic and antimicrobial activities dna interactions syntheses and structural investigations of new mono 4 nitrobenzyl spirocyclotriPhosphazenes
2016Co-Authors: Aytug Okumus, Zeynel Kilic, Tuncer Hokelek, Leyla Acik, Huseyin Akbas, Yasemin L Koc, Betul Aydin, Mustafa Turk, Hakan DalAbstract:The condensation reactions of hexachlorocyclotriphosphazene, N3P3Cl6, with N-alkyl-N′-mono(4-nitrobenzyl)diamines (1–3), NO2PhCH2NH(CH2) n NHR1 (R1 = CH3 or C2H5), led to the formation of the mono(4-nitrobenzyl)spirocyclotriPhosphazenes (4–6). The tetra-pyrrolidino (4a–6a), piperidino (4b–6b), and 1,4-dioxa-8-azaspiro[4,5]decaPhosphazenes (4c–6c) were prepared from(for) the reactions of partly substituted compounds (4, 5, and 6) with excess pyrrolidine, piperidine, and 1,4-dioxa-8-azaspiro[4,5]decane (DASD), respectively. The partly substituted geminal (4d and 5d) and cis-morpholino (6d) Phosphazenes were isolated from the reactions of excess morpholine in boiling THF and o-xylene, but the expected fully substituted compounds were not obtained. The structures of all the phosphazene derivatives were determined by elemental analyses, MS, FTIR, 1H, 13C{1H}, 31P{1H} NMR, HSQC, and HMBC techniques. The crystal structures of 4, 6, 4a, and 5a were verified by X-ray diffraction analysis. In addition, in vitro cytotoxic activities of fully substituted Phosphazenes (4a–6c) against HeLa cervical cancer cell lines (ATCC CCL-2) and the compounds 4a and 4c against breast cancer cell lines (MDA-MB-231) and L929 fibroblast cells were evaluated, respectively. Apoptosis effect was determined by MDA-MB-231 cancer cell lines and fibroblast cells. The MIC values of the compounds were in the ranges of 9.8–19.5 µM. The compounds 6, 5a, 6a, 5b, and 6d have greater MIC activity against bacterial and yeast strain. The investigation of DNA binding with the Phosphazenes was studied using plasmid DNA. The phosphazene derivatives inhibit the restriction endonuclease cleavage of plasmid DNA by BamHI and HindIII enzymes. BamHI and HindIII digestion results demonstrate that the compounds bind with G/G and A/A nucleotides.
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phosphorus nitrogen compounds part 28 syntheses structural characterizations antimicrobial and cytotoxic activities and dna interactions of new Phosphazenes bearing vanillinato and pendant ferrocenyl groups
2013Co-Authors: Yasemin Tumer, Nuran Asmafiliz, Zeynel Kilic, Tuncer Hokelek, Leyla Acik, Yasemin L Koc, Mehmet Lutfi Yola, Ali Osman Solak, Yagmur OnerAbstract:Abstract The gradually Cl replacement reactions of spirocyclic mono ( 1 and 2 ) and bisferrocenyl cyclotriPhosphazenes ( 3 – 5 ) with the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) gave mono ( 1a – 5a ), geminal ( gem - 1b – 5b ), non-geminal ( cis - 1b , cis - 5b and trans - 2b – 5b ), tri ( 1c – 5c ) and tetra-substituted Phosphazenes ( 1d – 5d ). Some Phosphazenes have stereogenic P-center(s). The chirality of 4c was verified using chiral HPLC column. Electrochemical behaviors were influenced only by the number of ferrocene groups, but not the length of the amine chains and the substituent(s). The structures of the new Phosphazenes were determined by FTIR, MS, 1 H, 13 C and 31 P NMR, HSQC and HMBC spectral data. The solid-state structures of cis - 1b and 4d were examined by single crystal X-ray diffraction techniques. The twelve phosphazene derivatives were screened for antimicrobial activity and the compounds 5a , cis - 1b and 2c exhibited the highest antibacterial activity against G(+) and G(−) bacteria. In addition, it was found that overall gem - 1b inhibited the growth of Mycobacterium tuberculosis . The compounds 1d , 2d and 4d were tested in HeLa cancer cell lines. Among these compounds, 2d had cytotoxic effect on HeLa cell in the first 48 h. Moreover, interactions between compounds 2a , gem - 1b , gem - 2b , cis - 1b , 2c , 3c , 4c , 5c , 1d , 2d and 4d , and pBR322 plasmid DNA were investigated.
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syntheses spectroscopic properties crystal structures biological activities and dna interactions of heterocyclic amine substituted spiro ansa spiro and spiro bino spiro Phosphazenes
2013Co-Authors: Selen Bilge Kocak, Zeynel Kilic, Asli Ozturk, Tuncer Hokelek, Serhat Kocoglu, Aytug Okumus, Yagmur Oner, Leyla AcikAbstract:The heterocyclic amine e. g. pyrrolidine, piperidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) substituted spiro-ansa-spiro (sas) 5a-5d and spiro-bino-spiro (sbs) 6a-6d Phosphazenes were prepared by the replacement reactions of the Cl-atoms in 3 and 4 with heterocyclic amines in dry THF (Scheme 1). All of the phosphazene derivatives were characterized by elemental analysis, FTIR, MS, 1D H-1, C-13 and P-31 NMR and DEPT and 2D HSQC techniques. The crystal structures of fully morpholine substituted sas 5c and sbs 6c Phosphazenes were verified by X-ray diffraction analysis. The relationships between exocyclic OPN bond angles (alpha') and delta P-OPN shifts, and the correlation of Delta(P-N) values and Delta(delta P) or delta P-OPN shifts were presented. The phosphazene derivatives (3, 4, 5a-5d and 6a-6d) were subjected to antimicrobial activity against six pathojen bacteria and two yeast strains. Fully pyrrolidine substituted sbs 6a was found to be quite active against yeast strain Candida tropicalis. In addition, the nature of the interactions of these compounds with pBR322 plasmid DNA was investigated, and the results displayed that partly substituted sas 3 and sbs 4 caused to cleave the DNA. (C) 2013 Elsevier B.V. All rights reserved.
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phosphorus nitrogen compounds 18 syntheses stereogenic properties structural and electrochemical investigations biological activities and dna interactions of new spirocyclic mono and bisferrocenylphosphazene derivatives
2009Co-Authors: Nuran Asmafiliz, Zeynel Kilic, Asli Ozturk, Tuncer Hokelek, Leyla Acik, Yasemin L Koc, Ozgul Kisa, Ali Albay, Zafer Ustundag, Ali Osman SolakAbstract:The reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6, with mono- (1 and 2) and bisferrocenyldiamines (3−5), FcCH2NH(CH2)nNHR1 (R1 = H or FcCH2−), produce mono- (6 and 7) and spirocyclic bisferrocenylPhosphazenes (8−10). The fully substituted Phosphazenes (11−15 and 18−21) are obtained from the reactions of corresponding partly substituted Phosphazenes (6−10) with excess pyrrolidine and NH2(CH2)3ONa, respectively. The reactions of 6 with 1-aza-12-crown-4 afford geminal (16) and tris (17) crown ether-substituted Phosphazenes. The structural investigations of the compounds have been verified by elemental analyses, mass spectrometry, Fourier transform IR, 1H, 13C, and 31P NMR, and DEPT, COSY, HETCOR, and HMBC techniques. The crystal structures of 7, 10, 11, and 15 have been determined by X-ray crystallography. In 16 and 17, there are one and two stereogenic P atoms, respectively, and they are expected to be in enantiomeric mixtures. The structures of 18−21 look similar to a propeller. In 20 and 21, the...
Zeynel Kilic - One of the best experts on this subject based on the ideXlab platform.
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phosphorus nitrogen compounds part 36 syntheses langmuir blodgett thin films and biological activities of spiro bino spiro trimeric Phosphazenes
2016Co-Authors: Nuran Asmafiliz, Zeynel Kilic, Leyla Acik, Betul Aydin, Mustafa Turk, Mehmet Civan, Orhan Avci, Yasemin L Gonder, Tuncer HokelekAbstract:The condensation reactions of hexachlorocyclotriphosphazene (N3P3Cl6, trimer) with the symmetric N2N2 or N2O2 donor type tetradentate bulky ligands (1–4) gave partly substituted spiro-bino-spiro (sbs) (5–8) trimeric Phosphazenes. Compounds 5–8 reacted with pyrrolidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) to give octapyrrolidino- (9–12), morpholino- (13–16) and DASD-substituted cyclotriPhosphazenes (17–20). The structures of the Phosphazenes have been elucidated using FTIR, MS, 1H, 13C{1H} and 31P{1H} NMR, and HSQC spectral data. The molecular and solid-state structures of 5, 6 and 12 were verified by single crystal X-ray diffraction techniques. On the other hand, the ultrathin and highly ordered Langmuir–Blodgett (LB) films of compounds 6, 7, 9 and 12 were also fabricated. The structural characterization of the LB films was made using p-polarized grazing angle (GAIR) and horizontal attenuated total reflectance (HATR) techniques. All the novel phosphazene derivatives were evaluated for antibacterial activities against Gram-positive (G+) and Gram-negative (G−) bacteria and for antifungal activities against yeast strains. In addition, the cytotoxic effects of compounds 9, 13, 15, 16, 19 and 20 were investigated against L929 fibroblast and MDA-MB-231 breast cancer cells. The most active one among these compounds was compound 9 at 6.25 μg mL−1 concentration. The interactions between compounds 5–20 and pBR322 plasmid DNA were determined by agarose gel electrophoresis.
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phosphorus nitrogen compounds part 33 in vitro cytotoxic and antimicrobial activities dna interactions syntheses and structural investigations of new mono 4 nitrobenzyl spirocyclotriPhosphazenes
2016Co-Authors: Aytug Okumus, Zeynel Kilic, Tuncer Hokelek, Leyla Acik, Huseyin Akbas, Yasemin L Koc, Betul Aydin, Mustafa Turk, Hakan DalAbstract:The condensation reactions of hexachlorocyclotriphosphazene, N3P3Cl6, with N-alkyl-N′-mono(4-nitrobenzyl)diamines (1–3), NO2PhCH2NH(CH2) n NHR1 (R1 = CH3 or C2H5), led to the formation of the mono(4-nitrobenzyl)spirocyclotriPhosphazenes (4–6). The tetra-pyrrolidino (4a–6a), piperidino (4b–6b), and 1,4-dioxa-8-azaspiro[4,5]decaPhosphazenes (4c–6c) were prepared from(for) the reactions of partly substituted compounds (4, 5, and 6) with excess pyrrolidine, piperidine, and 1,4-dioxa-8-azaspiro[4,5]decane (DASD), respectively. The partly substituted geminal (4d and 5d) and cis-morpholino (6d) Phosphazenes were isolated from the reactions of excess morpholine in boiling THF and o-xylene, but the expected fully substituted compounds were not obtained. The structures of all the phosphazene derivatives were determined by elemental analyses, MS, FTIR, 1H, 13C{1H}, 31P{1H} NMR, HSQC, and HMBC techniques. The crystal structures of 4, 6, 4a, and 5a were verified by X-ray diffraction analysis. In addition, in vitro cytotoxic activities of fully substituted Phosphazenes (4a–6c) against HeLa cervical cancer cell lines (ATCC CCL-2) and the compounds 4a and 4c against breast cancer cell lines (MDA-MB-231) and L929 fibroblast cells were evaluated, respectively. Apoptosis effect was determined by MDA-MB-231 cancer cell lines and fibroblast cells. The MIC values of the compounds were in the ranges of 9.8–19.5 µM. The compounds 6, 5a, 6a, 5b, and 6d have greater MIC activity against bacterial and yeast strain. The investigation of DNA binding with the Phosphazenes was studied using plasmid DNA. The phosphazene derivatives inhibit the restriction endonuclease cleavage of plasmid DNA by BamHI and HindIII enzymes. BamHI and HindIII digestion results demonstrate that the compounds bind with G/G and A/A nucleotides.
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phosphorus nitrogen compounds part 28 syntheses structural characterizations antimicrobial and cytotoxic activities and dna interactions of new Phosphazenes bearing vanillinato and pendant ferrocenyl groups
2013Co-Authors: Yasemin Tumer, Nuran Asmafiliz, Zeynel Kilic, Tuncer Hokelek, Leyla Acik, Yasemin L Koc, Mehmet Lutfi Yola, Ali Osman Solak, Yagmur OnerAbstract:Abstract The gradually Cl replacement reactions of spirocyclic mono ( 1 and 2 ) and bisferrocenyl cyclotriPhosphazenes ( 3 – 5 ) with the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) gave mono ( 1a – 5a ), geminal ( gem - 1b – 5b ), non-geminal ( cis - 1b , cis - 5b and trans - 2b – 5b ), tri ( 1c – 5c ) and tetra-substituted Phosphazenes ( 1d – 5d ). Some Phosphazenes have stereogenic P-center(s). The chirality of 4c was verified using chiral HPLC column. Electrochemical behaviors were influenced only by the number of ferrocene groups, but not the length of the amine chains and the substituent(s). The structures of the new Phosphazenes were determined by FTIR, MS, 1 H, 13 C and 31 P NMR, HSQC and HMBC spectral data. The solid-state structures of cis - 1b and 4d were examined by single crystal X-ray diffraction techniques. The twelve phosphazene derivatives were screened for antimicrobial activity and the compounds 5a , cis - 1b and 2c exhibited the highest antibacterial activity against G(+) and G(−) bacteria. In addition, it was found that overall gem - 1b inhibited the growth of Mycobacterium tuberculosis . The compounds 1d , 2d and 4d were tested in HeLa cancer cell lines. Among these compounds, 2d had cytotoxic effect on HeLa cell in the first 48 h. Moreover, interactions between compounds 2a , gem - 1b , gem - 2b , cis - 1b , 2c , 3c , 4c , 5c , 1d , 2d and 4d , and pBR322 plasmid DNA were investigated.
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syntheses spectroscopic properties crystal structures biological activities and dna interactions of heterocyclic amine substituted spiro ansa spiro and spiro bino spiro Phosphazenes
2013Co-Authors: Selen Bilge Kocak, Zeynel Kilic, Asli Ozturk, Tuncer Hokelek, Serhat Kocoglu, Aytug Okumus, Yagmur Oner, Leyla AcikAbstract:The heterocyclic amine e. g. pyrrolidine, piperidine, morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) substituted spiro-ansa-spiro (sas) 5a-5d and spiro-bino-spiro (sbs) 6a-6d Phosphazenes were prepared by the replacement reactions of the Cl-atoms in 3 and 4 with heterocyclic amines in dry THF (Scheme 1). All of the phosphazene derivatives were characterized by elemental analysis, FTIR, MS, 1D H-1, C-13 and P-31 NMR and DEPT and 2D HSQC techniques. The crystal structures of fully morpholine substituted sas 5c and sbs 6c Phosphazenes were verified by X-ray diffraction analysis. The relationships between exocyclic OPN bond angles (alpha') and delta P-OPN shifts, and the correlation of Delta(P-N) values and Delta(delta P) or delta P-OPN shifts were presented. The phosphazene derivatives (3, 4, 5a-5d and 6a-6d) were subjected to antimicrobial activity against six pathojen bacteria and two yeast strains. Fully pyrrolidine substituted sbs 6a was found to be quite active against yeast strain Candida tropicalis. In addition, the nature of the interactions of these compounds with pBR322 plasmid DNA was investigated, and the results displayed that partly substituted sas 3 and sbs 4 caused to cleave the DNA. (C) 2013 Elsevier B.V. All rights reserved.
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phosphorus nitrogen compounds 21 syntheses structural investigations biological activities and dna interactions of new n o spirocyclic phosphazene derivatives the nmr behaviors of chiral Phosphazenes with stereogenic centers upon the addition of chir
2010Co-Authors: Muhammet Isiklan, Nuran Asmafiliz, Ezgi Elif Ozalp, Elif Ece Ilter, Zeynel Kilic, Buenyemin Cosut, Serkan Yesilot, Adem Kilic, Asli Ozturk, Tuncer HokelekAbstract:The reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6, with N/O-donor-type N-alkyl (or aryl)-o-hydroxybenzylamines (1a−1e) produce mono- (2a−2e), di- (3a−3d), and tri- (4a and 4b) spirocyclic Phosphazenes. The tetrapyrrolidino monospirocyclic Phosphazenes (2f−2i) are prepared from the reactions of partly substituted compounds (2a−2d) with excess pyrrolidine. The dispirodipyrrolidinoPhosphazenes (3e−3h) and trispiroPhosphazenes (3i−3k) are obtained from the reactions of trans-dispiroPhosphazenes with excess pyrrolidine and sodium (3-amino-1-propanoxide), respectively. Compounds 3a−3d have cis and trans geometric isomers. Only the trans isomers of these compounds are isolated. Compounds 3a−3h have two stereogenic P atoms. They are expected to be in cis (meso) and trans (racemic) geometric isomers. In the trans trispiro compounds (3i−3k), there are three stereogenic P atoms. They are expected to be in racemic mixtures. The stereogenic properties of 3a−3k are confirmed by 31P NMR spectroscopy upon the a...
