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61.
62.
Cerium(III) nitrate hexahydrate efficiently catalyzes the three-component Biginelli reaction under solvent-free conditions of an aldehyde, a beta-keto ester or beta-diketone and urea or thiourea to afford the corresponding 3,4-dihydropyrimidin-2(1H)-ones or -thiones in excellent yields. 相似文献
63.
64.
Fariba Peytam Mehdi Adib Reihaneh Shourgeshty Mahmoud Rahmanian-Jazi Mehdi Jahani Bagher Larijani Mohammad Mahdavi 《Tetrahedron letters》2019,60(47):151257
An efficient, one-pot and three-component synthesis of a new series of 2-acyl-3,4,6-triaryl-1,4-dihydropyrazines is described. This two-step strategy involves treatment of phenacyl bromides and anilines to give the nucleophilic substitution intermediate followed by Michael-addition-cyclization to α-azidochalcones to afford the title compounds in high yields. 相似文献
65.
66.
Mehdi Adib MohammadHosein Sayahi Niusha Mahmoodi HamidReza Bijanzadeh 《Helvetica chimica acta》2006,89(6):1176-1180
The reactive 1 : 1 zwitterionic intermediate formed by the addition of isocyanides to dialkyl acetylenedicarboxylates was trapped with 4‐arylurazoles to produce the highly functionalized pyrazolo[1,2‐a][1,2,4]triazoles 5 in good yields (Table). The structures of the products 5a – h were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR), by EI‐MS, and elemental analysis. A possible mechanism for this reaction is proposed (Scheme). 相似文献
67.
Issa Yavari Mehdi Adib Hamid R. Bijanzadeh Majid M. M. Sadegi Hossein Logmani-Khouzani Javad Safari 《Monatshefte für Chemie / Chemical Monthly》2002,11(4):1109-1113
A dynamic NMR effect is observed in the 13C NMR spectra of anhydrous quinophthalone (quinoline yellow) and its monohydrate in the vicinity of 47°C and 0°C, respectively, and is attributed to a restricted rotation around the polarized carbon–carbon double bond. The free energy of activation for this process in anhydrous quinophthalone and the monohydrate is 65±2 and 55±2 kJ · mol−1, respectively, in CDCl3. 相似文献
68.
A catalyst-free and convenient protocol is described for the preparation of 3-aminoimidazo[1,2-a]pyridines and 5-aminoimidazo[2,1-b][1,3]thiazoles via three-component reactions between 2-aminopyridines or 2-aminothiazoles, aldehydes, and isocyanides in water in good to excellent yields. 相似文献
69.
Issa Yavari Mehdi Adib Shahrzad Abdolmohammadi Mansoreh Aghazadeh 《Monatshefte für Chemie / Chemical Monthly》2003,10(2):1093-1098
Protonation of the reactive 1:1 intermediate produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates with ethyl 2-(1-naphthylamino)-2-oxoacetate, leads to a vinylphosphonium salt, which undergoes intramolecular Wittig reaction to produce dialkyl 4-ethoxy-1-(1-naphthyl)-5-oxo-4,5-dihydro-1H-pyrrole-2,3-dicarboxylates in excellent yields. A dynamic NMR effect is observed in the 1H NMR spectra of the title compounds as a result of restricted rotation around the single bond linking the naphthalene moiety and the heterocyclic system, which is attributed to the peri interaction between the pyrrole residue and the peri CH group. The free energy of activation (G
) for this process is 58±2kJmol–1. 相似文献
70.
M. Shekarchi M. Pirali-Hamedani L. Navidpour N. Adib A. Shafiee 《Journal of the Iranian Chemical Society》2008,5(1):150-158
A new series of 3-aryl-5-(pyridin-3-yl)-1-thiocarbamoyl-2-pyrazoline derivatives (4a-j) were prepared by the reaction of azachalcons 3a-j with thiosemicarbazide in ethanolic sodium hydroxide. The structure of synthesized compounds were confirmed by 1H NMR and Mass spectral data. Their antibacterial activities against Escherichia coli (CTP 7624), Staphylococcus aureus (ATCC 6538), Staphylococcus epidermidis (ATCC 12229), Pseudomonas aeruginosa (ATCC 9027), Bacillus subtilis (ATCC 1156) and Micrococcus luteus (ATCC 9341) were investigated. Antifungal activity of compounds against Candida albicans and Candida globrata were found to be inactive. Compounds 4a-j were also evaluated for antituberculosis activity against Mycobacterium tuberculosis H 37 Rv (ATCC 27294) in BACTEC 12B using a broth microdilution assay and Microplate Alamar Blue Assay (MABA). The preliminary results showed that compounds 4e, 4d and 4g had 87%, 93% and 92% inhibitory effect respectively. 相似文献