فهرست مقالات diazotization

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  1 - A Synthetic Approach for Evaluation of Cytosinediazonium Susceptibility
  Kamahldin Haghbeen Shima Rezaeian Mehdi Bakavoli Fatemeh Mirazizi
  Reaction of a nucleobase with nitrosonium ion leads to its diazotization. Due to the instability,the nucleobase-diazonium assumingly falls in dediazotization and successive ring openingreactions. The resulting intermediate of the ring opening reaction is able to covalen چکیده کامل

  Reaction of a nucleobase with nitrosonium ion leads to its diazotization. Due to the instability,the nucleobase-diazonium assumingly falls in dediazotization and successive ring openingreactions. The resulting intermediate of the ring opening reaction is able to covalently cross-linkthe opposite strands of DNA. To examine this assumption for cytosine, some 4-amino-5-cyanopyrimidines were synthesized via [3+3] condensation of amidines with ethoxymethylenemalonitrile and successively converted to the corresponding 4-amino-5carboxyamido derivatives. These compounds were then exposed to nitrosonium ion under different conditions. Results of this study indicate that the diazonium of a 4-aminopyrimidine prefers deamination over the dediazotization. Therefore, the dediazotization and its successive ring-opening reactions of the pyrimidine cation would happen under some exceptionalconditions which deserve to be explored in more detailed studies. In view of the cytosinechemistry and cytotoxicity of NO, the results are presented and discussed. پرونده مقاله
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  2 - Convenient synthesis of tetrazolo[1,5-b]pyridazine derivatives
  Maryam Manasir Mohsen Nikpour
  Reaction of 3,6-dichloropyridazine with hydrazine gave 1-(6-chloropyridazin-3-yl) hydrazine in high yield in ethanol at room temperature. Diazotization of the latter compound converted it to 6-chlorotetrazolo[1,5-b]pyridazine quantitatively in ice bath. 6-Chlorotetrazol چکیده کامل

  Reaction of 3,6-dichloropyridazine with hydrazine gave 1-(6-chloropyridazin-3-yl) hydrazine in high yield in ethanol at room temperature. Diazotization of the latter compound converted it to 6-chlorotetrazolo[1,5-b]pyridazine quantitatively in ice bath. 6-Chlorotetrazolo[1,5-b]pyridazine underwent a chlorine substitution is ethanol with amines at room temperature.The reaction mechanism and spectral data is discussed. پرونده مقاله
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  3 - Investigation into the regioisomeric composition of some fused tetrazoles
  Paria Nasehi Omid Baravaye Sanaz Hafezi Birgani Mohsen Nikpour
  Treatment of 7-chloro-1-phenylpyrimido[4,5-e][1,3,4]thiadiazines with hydrazine in boiling ethanol gave corresponding7-hydrazinyl derivatives. Diazotization of the latter compounds acheived a mixture of 5H-tetrazolo[1',5':1,2]pyrimido[4,5-e][1,3,4]thiadiazine and 9H-tet چکیده کامل

  Treatment of 7-chloro-1-phenylpyrimido[4,5-e][1,3,4]thiadiazines with hydrazine in boiling ethanol gave corresponding7-hydrazinyl derivatives. Diazotization of the latter compounds acheived a mixture of 5H-tetrazolo[1',5':1,2]pyrimido[4,5-e][1,3,4]thiadiazine and 9H-tetrazolo[5',1':2,3]pyrimido[4,5-e][1,3,4]thiadiazines. Ratio of these two group of products determined by 1HNMR studies and no significant preference was observed for their formation. Efforts for separation of the products were unsuccessful and its reason is discussed. پرونده مقاله
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  4 - Polymer/HIO4 : An efficient catalyst for solvent-free synthesis of 2-naphthol azo dyes
  Abdolhamid Bamoniri Alireza Pourali Seyed Mohamad Reza Nazifi
  A convenient, one-pot method for the synthesis of diazonium salt has been developed by the sequential diazotization of aromatic amines with NaNO2, polymer- supported periodic acid (PPIA) and 2-naphthole under solvent-free conditions at room temperature. By using this me چکیده کامل

  A convenient, one-pot method for the synthesis of diazonium salt has been developed by the sequential diazotization of aromatic amines with NaNO2, polymer- supported periodic acid (PPIA) and 2-naphthole under solvent-free conditions at room temperature. By using this method, several types of aromatic amine, containing electron-withdrawing and electron-donating groups, were rapidly converted to the corresponding azo dyes in good to excellent yields. The ensuing aryl diazonium salts supported on polymer (aryl diazonium polymer), ArN2 +IO4 - were sufficiently stable to be kept at room temperature in the dry state. The use of mild reaction conditions and an inexpensive procedure are further advantages of this method. پرونده مقاله