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Malek T. Maghsoodlou Nourallah Hazeri Sayed M. Habibi-Khorassani Reza Heydari Ghasem Marandi Mojtaba Lashkari Khatereh Bagherpour Zahra Gharechaei 《Monatshefte für Chemie / Chemical Monthly》2010,39(5):351-356
Abstract
Synthesis of five phosphonato esters has been accomplished via reaction between dimethyl acetylenedicarboxylate and triphenyl phosphite in the presence of biological compounds such as theophylline, 4-hydroxypyrimidine, 2H-3,1-benzoxazine-2,4(1H)-dione, 2-chloroaniline, or 3-nitroaniline at ambient temperature. The configuration of the compounds was determined on the basis of coupling constants emerging from the Karplus equation. 相似文献3.
Razieh Doostmohammadi Malek Taher Maghsoodlou Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani 《中国化学快报》2013,24(10):901-903
A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed. 相似文献
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Maghsoodlou Malek Taher Habibi-Khorassani Sayyed Mostafa Heydari Reza Hazeri Nourollah Sajadikhah Seyed Sajad Rostamizadeh Mohsen 《中国化学》2010,28(2):285-288
Synthesis of α‐amino phosphonates is described under solvent‐free conditions at 100°C from reaction between aldehydes and amines in the presence of trialkyl phosphites using Al(H2PO4)3 as an efficient and reusable heterogeneous catalyst. The advantages of this procedure are short reaction time, flexibility and having high to excellent yields. 相似文献
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Malek Taher Maghsoodlou Sayyed Mostafa Habibi-Khorassani Zahra Shahkarami Nariman Maleki Mohsen Rostamizadeh 《中国化学快报》2010,21(6):686-689
<正>2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl chloride catalysts the reaction is limited to give only 1,8-dioxo-octahydroxanthenes 3a-k in very good yields. 相似文献
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Malek Taher Maghsoodlou Ghasem Marandi Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani Ali Akbar Mirzaei 《Molecular diversity》2011,15(1):227-231
5-Aryl-6-(alkyl- or aryl-amino)-1,3-dimethylfuro [2,3-d]pyrimidine derivatives were obtained by in situ reaction alkyl or aryl isocyanides and pyridinecarbaldehyde derivatives in
the presence of 1,3-dimethylbarbituric acid in dichloromethane without any prior activation or modifications. 相似文献
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Mehdi Shahraki Sayyed Mostafa Habibi-Khorassani Ali Ebrahimi Malektaher Maghsoodlou Younes Ghalandarzehi 《Structural chemistry》2013,24(2):623-635
The chemoselectivity of geometrically ylide compounds is often hard to assign from experimental techniques, particular system with intramolecular hydrogen bonding (IHB) are even more challenging. Herein, theoretical calculations were performed to investigate whether theoretical results would provide consistent evidence for the existence of IHB to confirm experimental data and to evaluate strength of the N–H···O IHB from geometrical synthesized 2-substituted pyrrole stable phosphorus ylide (dimethyl 2-(1H-pyrrol-2-yl)-3-(triphenylphosphoranylidene) butanedioate in a single chemoselective compound. Topological parameters at the bond critical points (BCP) of intramolecular hydrogen bonds from Bader’s atoms in molecules (AIM) theory and Winhold’s natural bond orbital (NBO) calculations were analyzed at the B3LYP/6-311++g** level in details. A series of gage-including atomic orbital chemical shift (GIAO c.s.) calculations at the HF and DFT levels of theory were carried out to assign the 1H NMR chemical shifts. The best prediction of the experimental 1H NMR values was obtained at the mPW1PW91 levels using the 6-31G** basis set. Theoretical results, in agreement with the experimental data, were confirmed the N–H···O IHB was caused the deshielding of the proton to lower field. The barriers in double bond and single bond rotation were theoretically estimated in detailed and the AIM and NPA approaches were confirmed the loss of charge of the hydrogen atom involving in intramolecular N–H···O hydrogen bonding. The geometrical and topological parameters from AIM and NBO analyses were indicated the medium N–H···O IHB. 相似文献
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Maghsoodlou MT Habibi-Khorassani SM Heydari R Hassankhani A Marandi G Nassiri M Mosaddeg E 《Molecular diversity》2007,11(2):87-91
A new one-pot, simple and effective procedure is presented for the preparation of O-containing phosphorus ylides by the Michael
addition reaction of N-methylpyrrole-2-carbaldehydoxime, pyridin-2-carbaldehydoxime or acetophenonoxime with acetylenic esters. 相似文献
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Ebrahimi A Habibi-Khorassani M Bazzi S 《Physical chemistry chemical physics : PCCP》2011,13(8):3334-3343
The enzyme-substrate contacts that are believed to be involved in depurination by proton transfer have been modelled by protonation and deprotonation of 3-methyl-2'-deoxyadenosine (3-MDA) using quantum mechanical calculations in the gas-phase and solution media. The change in the charge distribution on the sugar ring and nucleobase that is introduced by the protonation and deprotonation strongly affects the N-glycosidic bond length. The unimolecular cleavage and hydrolysis of the N-glycosidic bond, involving D(N)*A(N) and A(N)D(N) pathways, have been considered at several levels of theory. The trend in the energy barriers is A(N)D(N) > cleavage > D(N)*A(N). All probable proton transfer reactions resulting from enzyme-substrate contacts do not facilitate the N-glycosidic bond cleavage of 3-MDA. The deprotonation of 3-MDA that may result from the interaction between H6 and enzyme do not facilitate bond cleavage. The protonation at N7 induces more positive charge on the sugar ring and further facilitates the depurination relative to the protonation at N1. The changes in the charges calculated on the ribose and nucleobase are in good relationship with the C1'-C2', C1'-O4', and N-glycosidic bond lengths along the cleavage. The change in energy barrier ΔE of glycosidic bond cleavage from the gas-phase to solution media strongly depends on the charge of the species. 相似文献
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