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Preparation, Characterization, And Potentiometric Titrations Of Some New Di-[3-(3-Alkyl/Aryl-4,5-Dihydro-1h-1,2,4-Triazol-5-One-4-Yl)-Azomethinphenyl] Isophthalate/Terephthalate Derivatives, Haydar Yüksek, Özlem Gürsoy Kol
Preparation, Characterization, And Potentiometric Titrations Of Some New Di-[3-(3-Alkyl/Aryl-4,5-Dihydro-1h-1,2,4-Triazol-5-One-4-Yl)-Azomethinphenyl] Isophthalate/Terephthalate Derivatives, Haydar Yüksek, Özlem Gürsoy Kol
Turkish Journal of Chemistry
3-Alkyl(Aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) reacted with di-(3-formylphenyl) isophthalate (3) and di-(3-formylphenyl) terephthalate (6) to afford the corresponding 6 novel di-[3-(3-alkyl/aryl-4,5-dihydro-1H-1,2,4-triazol-5-one-4-yl)- azomethinphenyl] isophthalates (4) and 6 novel di-[3-(3-alkyl/aryl-4,5- dihydro-1H-1,2,4-triazol-5-one-4-yl)-azomethinphenyl] terephthalates (7), respectively. The acetylation reactions of compounds 4 and 7 were investigated, and 5 and 8 type compounds were obtained, respectively. The new compounds synthesized were characterized by using IR, ^1H-NMR, ^{13}C-NMR, and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 4 and 7 were titrated potentiometrically with tetrabutylammonium hydroxide in 5 non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide, acetone, …
Compounds Isolated From Tannacetum Polycephalum, . Azizuddin, Muhammad Iqbal Choudhary
Compounds Isolated From Tannacetum Polycephalum, . Azizuddin, Muhammad Iqbal Choudhary
Turkish Journal of Chemistry
Several known secondary metabolites, namely lupeol (1), \beta-sitosterol (2), stigmasterol (3), and 2,6-dimethoxy-4-hydroxy acetophenone (4) were isolated from a folkloric medicinal plant, Tannacetum polycephalum. The structures of these compounds were elucidated on the basis of various spectroscopic methods.
Synthesis And Characterizations Of Some New 4h-1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şule Ceylan, Deni̇z Şahi̇n
Synthesis And Characterizations Of Some New 4h-1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şule Ceylan, Deni̇z Şahi̇n
Turkish Journal of Chemistry
3-[(5-Amino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-alkyl-4H-1,2,4-triazoles (2a,b) were obtained from the reaction of 3-cyanomethyl-5-alkyl-4-ethoxycarbonylamino-4H-1,2,4-triazoles (1a,b) with thiosemicarbazide in the presence of trifluoroacetic acid. The treatment of the obtained compounds (2a,b) with acetic anhydride for 1 h afforded 3-[(5-acetylamino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-alkyl-4H-1,2,4-triazoles (3a,b). The synthesis of 4-ethoxycarbonylamino-3-[(2,3-dihydro-1,3-benzoxazol-2-yl)methyl]-5-(4-methylbenzyl)-4H-1,2,4-triazole (4) was performed by the treatment of 3-[(5-acetylamino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-(4-methylbenzyl)-4H-1,2,4-triazole (3a) with o-aminophenol under nitrogen atmosphere for 50 h. The reaction of compounds 1a,b with salicylaldehyde in the presence of sodium ethoxide yielded 2-{4-[(ethoxycarbonyl)amino]-5-alkyl-4H-1,2,4-triazol-3-yl}-3-(2-hydroxyphenyl)-acrylonitriles (5a,b). The acetylations of compounds 5a,b with acetic anhydride for 5 h resulted in the formation of 2-{4-[acetyl(ethoxycarbonyl)amino]-5-alkyl-4H-1,2,4-triazol-3-yl}-3-[2-(acetyloxy)phenyl]-acrylic acids (6a,b). On the other hand, the treatment of compounds 5a,b with …
The Synthesis And Anticonvulsant Activity Of 1-Substituted-7-Methoxy-1,2,4-Triazolo [4,~3-A]Quinoline, Li-Ping Guan, Xian-Yu Sun, Guan-Rong Tian, Kyu-Yun Chai, Zhe-Shan Quan
The Synthesis And Anticonvulsant Activity Of 1-Substituted-7-Methoxy-1,2,4-Triazolo [4,~3-A]Quinoline, Li-Ping Guan, Xian-Yu Sun, Guan-Rong Tian, Kyu-Yun Chai, Zhe-Shan Quan
Turkish Journal of Chemistry
A new series of 1-substituted-7-methoxy-5-phenyl-1,2,4-triazolo [4,3-a]quinolines were synthesized using ethyl-3-oxo-3-phenylpropanoate and 4-methoxybenzenamine as the starting material. Their anticonvulsant activity was evaluated by the maximal electroshock (MES) test and 7-methoxy-5-phenyl-1,2,4-triazolo[4,3-a]quinoline (4a) was identified as the most potent compound, with an ED_{50} value of 9.2 mg kg^{-1}, which is comparable to the reference drug phenytoin (ED_{50} = 9.9 mg kg^{-1}). To explore the possible mechanism of its anticonvulsant activity, compound 4a was tested with the rotarod neurotoxicity test, pentylenetetrazole (sc-PTZ) test, and isoniazid test. Compound 4a had a higher protective index (PI = TD_{50}/ED_{50}) value (16.6) than phenytoin (PI = 7.0), and …
Synthesis And Characterization Of New Tridentate Iminooxime Ligands And Their Co(Iii) Complexes, Hasene Mutlu, Gazi̇ İrez
Synthesis And Characterization Of New Tridentate Iminooxime Ligands And Their Co(Iii) Complexes, Hasene Mutlu, Gazi̇ İrez
Turkish Journal of Chemistry
In this study, (hydroxyimino)(2-phenyl(1,2,3,4-tetrahydroquinazolin- 2-yl))methane (H_2L^1) and (hydroxyimino)(2-(2-thienyl)(1,2,3,4- tetrahydroquinazolin-2-yl))methane (H_2L^2) were synthesized by the condensation of 2-(hydroxyimino)-1-phenylethan-1-one (INAP) and 2-(hydroxyimino)-1-(2-thienyl)ethan-1-one (INAT) with 2-aminobenzylamine (2-ABA). Complexes of these ligands with Co^{3+} were prepared with a metal:ligand ratio of 1:2. The ligands and their complexes were elucidated on the basis of elemental analyses, AAS, FT-IR, ^1H- and ^{13}C-NMR spectra, mass spectra, magnetic susceptibility measurements, and molar conductivity.
A New And Convenient Method Of Generating Alkyl Isocyanates From Alcohols, Thiols, And Trimethylsilyl Ethers Using A 2,4,6-Trichloro[1,3,5] Triazine/N-Bu_4nocn, Batool Akhlaghinia, Sima Samiei
A New And Convenient Method Of Generating Alkyl Isocyanates From Alcohols, Thiols, And Trimethylsilyl Ethers Using A 2,4,6-Trichloro[1,3,5] Triazine/N-Bu_4nocn, Batool Akhlaghinia, Sima Samiei
Turkish Journal of Chemistry
Alkyl isocyanates are prepared in good to excellent yields by treatment of alcohols, thiols, and trimethylsilyl ethers with 2,4,6-trichloro[1,3,5] triazine/n-Bu_4NOCN in acetonitrile. This method is highly selective for conversion of 1° alcohols to alkyl isocyanates in the presence of 2° and 3° alcohols, thiols, and trimethylsilyl ethers.
Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi
Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi
Turkish Journal of Chemistry
Alcohols and phenols were tetrahydropyranylated in the presence of 2,4,6-trichloro[1,3,5]triazine in good to excellent yields in acetonitrile.
Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle
Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle
Turkish Journal of Chemistry
The reaction of amidrazones 1 with \alpha-haloesters 2 formed 1,3,5-substituted 4,5-dihydro-1,2,4-triazin-6-ones (4a-z) rather than 1,2,4-triazin-5-one derivatives (5a-z). The microanalysis and spectral data of the synthesized compounds are in full agreement with their molecular structure.
Synthesis And Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, . Lutfullah, Ahmad Umar, Mohammed Muzibur Rahman, Mohammad Mansoob Khan, Yoon Bong Hahn
Synthesis And Physico-Chemical And Spectroscopic Investigations Of Sodium Dihydrobis(1,2,3-Benzotriazolyl)Borate Ligand And Its Transition Metal Complexes, . Lutfullah, Ahmad Umar, Mohammed Muzibur Rahman, Mohammad Mansoob Khan, Yoon Bong Hahn
Turkish Journal of Chemistry
The title ligand, sodium dihydrobis(1,2,3-benzotriazolyl)borate, Na[H_2B(BTz)_2], was synthesized by refluxing 1 mole of sodium borohydride with 2 moles of 1,2,3- benzotriazole in toluene. The ligand shows ample reactivity towards Cr(III), Mn(II), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ions and forms stable complexes. The ligand and its metal complexes were characterized by physico-chemical and spectroscopic techniques. All the complexes of divalent metal ions are tetrahedral except for Cu(II), which has been proposed to have a square-planar geometry. The complexes of Cr(III) and Fe(III) appear to have an octahedral geometry. The magnitude of molar conductance of 10^{-3} M …
Synthesis Of Some New 1-Acylthiosemicarbazides And 1,2,4-Triazol-5-Thiones, And Their Analgesic And Anti-Inflammatory Activities, Yasemi̇n Dündar, Bi̇lge Çakir, Esra Küpeli̇, M. Fethi̇ Şahi̇n, Ni̇ngur Noyanalpan
Synthesis Of Some New 1-Acylthiosemicarbazides And 1,2,4-Triazol-5-Thiones, And Their Analgesic And Anti-Inflammatory Activities, Yasemi̇n Dündar, Bi̇lge Çakir, Esra Küpeli̇, M. Fethi̇ Şahi̇n, Ni̇ngur Noyanalpan
Turkish Journal of Chemistry
We synthesized new 1-[3-(2-oxobenzothiazolin-3-yl)propanoyl]-4- substituted-thiosemicarbazides and their corresponding cyclized 3-[2-(2-oxobenzothiazoline-3-yl)ethyl]-4-substituted-1,2,4-triazol-5-thione ana-logs in which position 4 of the triazole ring was substituted by cyclohexyl, methyl, allyl, phenyl, p-methylphenyl, p-methoxyphenyl, p-chlorophenyl, p-nitrophenyl, benzyl, and phenylethyl to screen their analgesic and anti-inflammatory activities as well as gastric ulceration potential in test animals. None of the compounds, except 5a, 5e, and 5h, caused gastric lesions or bleeding. Compound 5g was found to have higher analgesic and anti-inflammatory activity among the synthesized compounds.
Synthesis Of Some Novel 3,5-Diaryl-1,2,4-Triazole Derivatives And Investigation Of Their Antimicrobial Activities, Mevlut Serdar, Nurhan Gümrükçüoğlu, Şengül Alpay Karaoğlu, Nesli̇han Demi̇rbaş
Synthesis Of Some Novel 3,5-Diaryl-1,2,4-Triazole Derivatives And Investigation Of Their Antimicrobial Activities, Mevlut Serdar, Nurhan Gümrükçüoğlu, Şengül Alpay Karaoğlu, Nesli̇han Demi̇rbaş
Turkish Journal of Chemistry
A series of acylhydrazones (2a-d) was synthesized from the reactions of iminoester hydrochlorides (1a-e) with acyl hydrazines. 2,5-Dialkyl 1,3,4-oxadiazoles (3a-d) were obtained in the same reaction media. The treatment of acylhydrazones with hydrazine hydrate afforded 4-amino-3,5-dialkyl-1,2,4-triazoles (4a-c). The acetylation of 4-amino-3-(4-hydroxyphenyl)-5-phenyl-4H-1,2,4-triazole (4a) produced 4-amino-5-(4-acetoxyphenyl)-3-phenyl-4H-1,2,4-triazole (9), while the acetylation of 4-amino-3-(4-tolyl)-5-phenyl-4H-1,2,4-triazole (4b) gave 4-acetylamino-3-phenyl-5-(4-tolyl)-4H-1,2,4-triazole (10). The treatment of compound 4b with various aromatic aldehydes or acetophenone and 4-nitroacetophenone resulted in the formation of 4-arylidenamino-3,5-dialkyl-4H-1,2,4-triazoles (5a-e and 7a,b). Sodium borohydride reduction of 4-arylidenamino derivatives of 1,2,4-triazoles afforded 4-alkylamino-3,5-dialkyl-4H-1,2,4-triazoles (6a-e and 8a,b). All newly synthesized compounds were screened for their antimicrobial and antifungal …
Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nurhan Gümrükçüoğlu, Mevlut Serdar, Eli̇f Çeli̇k, Ali̇ Sevi̇m, Nesli̇han Demi̇rbaş
Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nurhan Gümrükçüoğlu, Mevlut Serdar, Eli̇f Çeli̇k, Ali̇ Sevi̇m, Nesli̇han Demi̇rbaş
Turkish Journal of Chemistry
A series of acylhydrazones (2a-f) were synthesized by the condensation of iminoester hydrochlorides (1a-f) with acyl hydrazines. 2,5-Dialkyl 1,3,4-oxadiazoles (3a,c,e) were obtained in the same reaction media. The treatment of acylhydrazones with hydrazine hydrate afforded 4-amino-3,5-dialkyl-1,2,4-triazoles (4a-c). The acetylation of 4-amino-3,5-dialkyl-1,2,4-triazoles produced N-[3,5-dialkyl-4H-1,2,4-triazol-4-yl] acetamides (5-7). The treatment of compounds 4a and 4c with various aromatic aldehydes resulted in the formation of 4-arylidenamino-3,5-dialkyl-1,2,4-triazoles (8a,d, e, and 10a-e). Sodium borohydride reduction of 4-arylidenamino derivatives afforded 4-alkylamino-3,5-dialkyl-1,2,4-triazoles (9a,d, e, and 11a-e). Compounds 4b, 4c, 7, 8d, and 11c showed good antifungal activity only against yeast-like fungi, while compounds 3e, 6, 8e, and 9e …
Synthesis And Anticancer Evaluation Of Some New Unsymmetrical 3,5-Diaryl-4h-1,2,4-Triazole Derivatives, Olcay Beki̇rcan, Bahi̇tti̇n Kahveci̇, Murat Küçük
Synthesis And Anticancer Evaluation Of Some New Unsymmetrical 3,5-Diaryl-4h-1,2,4-Triazole Derivatives, Olcay Beki̇rcan, Bahi̇tti̇n Kahveci̇, Murat Küçük
Turkish Journal of Chemistry
A series of 4-arylidenamino-4H-1,2,4-triazole derivatives (3-11) were synthesized from the treatment of 4-amino-4H-1,2,4-triazoles (2) with certain aldehydes. Compounds 3-11 were reduced with NaBH_4 to afford the corresponding 4-arylmethylenamino-4H-1,2,4-triazoles (12-20). Compounds 1-10 and 12-19 were characterized by elemental analyses and ^1H NMR, ^{13}C NMR, IR and UV spectral data. Compounds 11 and 20 were characterized by ^1H NMR, ^{13}C NMR, IR and mass spectral data. Compounds 14, 16, 17, and 18 were tested for anticancer activities. Compound 17, chosen for its higher anticancer activity in the preliminary tests with the cancer cell lines of MCF7, NCI-H460, and SF-268, exhibited remarkable anticancer …
Synthesis Of Mannich Bases Of Some 2,5-Disubstituted 4-Thiazolidinones And Evaluation Of Their Antimicrobial Activities, Handan Altintaş, Öznur Ateş, Seher Bi̇rteksöz, Gülten Ötük, Meltem Uzun, Di̇lek Şanata
Synthesis Of Mannich Bases Of Some 2,5-Disubstituted 4-Thiazolidinones And Evaluation Of Their Antimicrobial Activities, Handan Altintaş, Öznur Ateş, Seher Bi̇rteksöz, Gülten Ötük, Meltem Uzun, Di̇lek Şanata
Turkish Journal of Chemistry
4-Carbethoxymethyl-2-[(\alpha -chloropropionyl/\alpha -bromobutyryl/\alpha-chloro-(\alpha-phenyl)acetyl)amino]thiazoles (2a-c) were synthesized by the reaction of 4-carbethoxymethyl-2-aminothiazole (1) with \alpha-chloropropionyl chloride, \alpha-bromobutyryl bromide and \alpha-chloro-\alpha -phenylacetyl chloride, respectively, which were then refluxed with ammonium thiocyanate to obtain 5-substituted 2-[(4-carbethoxymethylthiazol-2-yl)imino]-4-thiazolidinones (3a-c). 3a-c were stirred with formaldehyde and various secondary amines to gain 15 novel compounds with the structure 5-substituted 5-(N,N-disubstituted aminomethyl)-2-[(4-carbethoxymethylthiazol-2-yl)imino]-4- thiazolidinones (4a-o). The antibacterial activities of the compounds against S. aureus ATCC 6538, S. epidermidis ATCC 12228, E. coli ATCC 8739, K. pneumoniae ATCC 4352, P. aeruginosa ATCC 1539, S. typhi, Sh. flexneri and Pr. mirabilis ATCC 14153 were tested using disk diffusion, while the antifungal …
Synthesis And Characterization Of New Triheterocyclic Compounds Consisting Of 1,2,4-Triazol-3-One, 1,3,4-Thiadiazole And 1,3,4-Oxadiazole Rings, Nesli̇han Demi̇rbaş
Synthesis And Characterization Of New Triheterocyclic Compounds Consisting Of 1,2,4-Triazol-3-One, 1,3,4-Thiadiazole And 1,3,4-Oxadiazole Rings, Nesli̇han Demi̇rbaş
Turkish Journal of Chemistry
A series of acetic acid derivatives (2a-c) was synthesized by the condensation of compounds 1a-c with chloroacetic acid. The treatment of carboxylic acid derivatives with thiosemicarbazide in phosphorus oxychloride and subsequent diazotation of the products (3a-c) afforded 5-alkyl-2-[(5-chloro-1,3,4-thiadiazol-2-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (4a-c). The treatment of compounds 4a-c with thiourea produced 5-alkyl-2-[(5-mercapto-1,3,4- thiadiazol-2-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (5a-c). Subsequently, compounds 5a-c were converted to acid hydrazides by treatment with hydrazine hydrate after esterification (7a-e). Moreover, the reaction of compounds 7a-c with carbon disulfite in the presence of KOH afforded 5-alkyl-2-[(5-\{[(5- mercapto-1,3,4-oxadiazol-2-yl)methyl]thio\}-1,3,4-thiadiazol-2-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-ones (8a-c).
Synthesis Of Novel 4-Alkylidene- And 4-Alkylamino-5-Oxo-4,5-Dihydro-[1,2,4] Triazole Derivatives And Investigation Of Their Antitumor Activities, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu
Synthesis Of Novel 4-Alkylidene- And 4-Alkylamino-5-Oxo-4,5-Dihydro-[1,2,4] Triazole Derivatives And Investigation Of Their Antitumor Activities, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu
Turkish Journal of Chemistry
A series of novel 3-alkyl-4-cyclohexylmethylenamino-5-oxo-4,5-dihydro-[1,2,4]triazoles (6a-e) and 3-alkyl-4-hexylidenamino-5-oxo-4,5-dihydro-[1,2,4]triazoles (7b-e) were synthesized from the reaction of corresponding 3-alkyl-4-amino-5-oxo-4,5-dihydro-[1,2,4]triazoles (1) with cyclohexancarboxaldehyde and capronaldehyde. The acetylation of compounds 6e and 7b resulted in the formation of 1-acetyl-4- cyclohexylmethylenamino-5-oxo-3-(p-tolyl)-4,5-dihydro-[1,2,4]triazole (10) and 3-benzyl-4-hexylidenamino-5-oxo-4,5-dihydro-[1,2,4]triazole (11). 3-Alkyl-4-cyclohexylmethylamino-5-oxo-4,5-dihydro-[1,2,4]triazoles (8a-e) and 3-alkyl-4-hexylamino-5-oxo-4,5-dihydro-[1,2,4]triazoles (9b-e) were obtained from the selective reduction of compounds 6a-e and 7b-e with NaBH_4. The in vitro antitumor activity of some selected compounds was screened by the National Cancer Institute (USA) against several human tumor cell lines, and compounds 8c, 9d and 11c were found to be active.
Synthesis And Antitumor Activities Of Some New 4-(1-Naphthylidenamino)- And 4-(1-Naphthylmethylamino)-1,2,4-Triazol-5-One Derivatives, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu
Synthesis And Antitumor Activities Of Some New 4-(1-Naphthylidenamino)- And 4-(1-Naphthylmethylamino)-1,2,4-Triazol-5-One Derivatives, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu
Turkish Journal of Chemistry
A series of 4-(1-naphthylidenamino)-1,2,4-triazol-5-one derivatives (3a-e) were synthesized by condensation of corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones with 1-naphthaldehyde. Acetylation and alkylation of these compounds gave 4a-e and 5a-e, respectively. Sodium borohydride reduction of 1-naphthylidenamino derivatives afforded naphthylmethylamino derivatives, which were subsequently acetylated. Depending on the duration of the acetylation, mono or bis acetamide derivatives were obtained. The in vitro antitumor activities of some selected compounds were screened and compounds 3e, 5c, 6e and 9c} were found to be active.
Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat
Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat
Turkish Journal of Chemistry
1,3-Dipolar cycloaddition of imidazoline 3-oxides 1 with methylisothiocyanate proceeds regio- and diastereoselectively to give tetrahydroimidazo[1,5-b][1,2,4]oxadiazol-2(1H)-thiones 3 in high yields. The cis configuration of the adducts was proved by our double cis elimination test as well as by NOESY experiments. Adducts 3a-c undergo ring opening at reflux in acetonitrile to give imidazoles while 3d-e undergo retro dipolar cycloaddition to give the starting nitrones 1d-e. The imidazooxadiazol-2-thiones 3a-e were treated with concentrated HCl in ethanol at 50 °C to give the corresponding 4H-[1,2,4]oxadiazole-5-thione only in cases in which the substituent at C-6 is an aryl.
A Convenient Synthesis Of 3,6-Disubstituted-1,4-Dihydro-[1,2,4,5]Tetrazines And Preparation Of New Acetic Acid Derivatives Containing 5-Oxo-4-Phenylamino- 4,5-Dihydro-[1,2,4]Triazole, Ahmet Demi̇rbaş
Turkish Journal of Chemistry
A series of compounds 8a-e, was synthesized by condensation of compounds 7a-e with ethyl bromoacetate. The treatment of compounds 8a-e with hydrazine hydrate afforded the corresponding hydrazide derivatives (9a-e). Subsequently, compounds 9a-e were converted to alkylidene hydrazides (10a-e). Moreover, upon heating in the presence of carboxylic acids, compounds 9a-e unexpectedly gave 1,4-dihydro-[1,2,4,5]tetrazine derivatives (11a-e).
Phenolic, Megastigmane, Nucleotide, Acetophenon And Monoterpene Glycosides From Phlomis Samia And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher
Phenolic, Megastigmane, Nucleotide, Acetophenon And Monoterpene Glycosides From Phlomis Samia And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher
Turkish Journal of Chemistry
Phytochemical investigations on the aerial parts of Phlomis samia resulted in the isolation of a simple phenolic glucoside, 2,6-dimethoxy-4-hydroxyphenol-1-O-\beta -D-glucopyranoside (1); a megastigmane glucoside, phlomuroside (=3-hydroxy-5,6-epoxy-\beta -ionol-9-O-\beta -D-glucopyranoside) (2); and a nucleotide glycoside, uridine (3). From the aerial parts of P. carica, the same phenolic glucoside, 2,6-dimethoxy-4-hydroxyphenol-1-O-\beta -D-glucopyranoside (1); as well as an acetophenon glucoside, picein (4); and 2 monoterpenoid glucosides, - betulalbuside A (5) and 1-hydroxylinaloyl-6-O-\beta -D-glucopyranoside (6) - were isolated and identified. The structure elucidation of the isolates was based on spectroscopic evidence.
Synthesis And Characterization Of Some 3-Alkyl-4-Amino-5-Cyanomethyl-4h-1,2,4-Triazoles, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Kemal Sancak
Synthesis And Characterization Of Some 3-Alkyl-4-Amino-5-Cyanomethyl-4h-1,2,4-Triazoles, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Kemal Sancak
Turkish Journal of Chemistry
The preparation and characterization of some 3-alkyl-4-amino-5-cyanomethyl-4H-1,2,4-triazoles with active methylene groups are described and their structural properties using NMR and IR spectra and elemental analyses are given.
A Quantum-Chemical Investigation On 5,5'-Bi(1h-1.2,4-Triazole)), A. A. İki̇zler, R. Abbasoğlu, N. Saltek, M. Şeri̇fova
A Quantum-Chemical Investigation On 5,5'-Bi(1h-1.2,4-Triazole)), A. A. İki̇zler, R. Abbasoğlu, N. Saltek, M. Şeri̇fova
Turkish Journal of Chemistry
The conformational analysis of flexible 5,5'-bi(1H-1,2,4-triazole) molecule containing various reaction centers has been performed by the semiempirical methods MNDO,AM1 and PM3, and the internal rotation barrier calculated. The most stable conformation of the molecule has been determined to be the planar trans conformation. According to the three methods, 5,5'-bi(1H-1,2,4-triazole) molecule (C) has been found to be relatively more stable than its tautomer 3,3'-bi(1H-1,2,4-triazole)(B) and to be less stable than its other tautomer 3,3'-bi(4H-1,2,4-triazole)(A). Moreover, the electronic properties of 5,5'-bi(1H-1,2,4-triazole) molecule and the effect of conformational changing on electronic and geometric properties have also been investigated. To determine the protonation sites …