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141.
Nishiwaki N Nishida D Ohnishi T Hidaka F Shimizu S Tamura M Hori K Tohda Y Ariga M 《The Journal of organic chemistry》2003,68(22):8650-8656
The acyl group of an alpha-aryl-beta-keto ester was readily transferred to N-, O-, and S-nucleophiles. The transacylation from arylated diethyl 3-oxoglutarate to amines led to unsymmetrical malonic acid amide esters in high yields. The present reaction proceeded under mild conditions without formation of detectable byproducts. Only simple experimental manipulations were required. This reaction was also found to be sensitive to steric factors, which enabled the chemoselective monoacylation of diamines and amino alcohols without any modifications such as protection. 相似文献
142.
One-photon mass-analyzed threshold ionization (MATI) spectrum of CH2BrI was obtained using coherent vacuum-ultraviolet radiation generated by four-wave difference-frequency mixing in Kr. Unlike CH2ClI investigated previously, a very extensive bending (Br-C-I) progression was observed. Vibrational frequencies of CH2BrI+ were measured from the spectra and the vibrational assignments were made by utilizing frequencies calculated by the density-functional-theory (DFT) method using relativistic effective core potentials with and without the spin-orbit terms. A noticeable spin-orbit effect on the vibrational frequencies was observed from the DFT calculations, even though its influence was not so dramatic as in CH2ClI+. A simple explanation based on the bonding characteristics of the molecular orbitals involved in the ionization is presented to account for the above differences between the MATI spectra of CH2BrI and CH2ClI. The 0-0 band of the CH2BrI spectrum could be identified through the use of combined data from calculations and experiments. The adiabatic ionization energy determined from the position of this band was 9.5944+/-0.0006 eV, which was significantly smaller than the vertical ionization energy reported previously. 相似文献
143.
Lavinia L. Ruta Ileana C. Farcasanu Mihaela Bacalum Mina Rileanu Arpad Mihai Rostas Constantin Daniliuc Mariana Carmen Chifiriuc Luminia Mruescu Marcela Popa Mihaela Badea Emilia Elena Iorgulescu Rodica Olar 《Molecules (Basel, Switzerland)》2021,26(22)
Novel complexes of type [Cu(N-N)(dmtp)2(OH2)](ClO4)2·dmtp ((1) N-N: 2,2′-bipyridine; (2) L: 1,10-phenantroline and dmtp: 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine) were designed in order to obtain biologically active compounds. Complexes were characterized as mononuclear species that crystallized in the space group P-1 of the triclinic system with a square pyramidal geometry around the copper (II). In addition to the antiproliferative effect on murine melanoma B16 cells, complex (1) exhibited low toxicity on normal BJ cells and did not affect membrane integrity. Complex (2) proved to be a more potent antimicrobial in comparison with (1), but both compounds were more active in comparison with dmtp—both against planktonic cells and biofilms. A stronger antimicrobial and antibiofilm effect was noticed against the Gram-positive strains, including methicillin-resistant Staphylococcus aureus (MRSA). Both electron paramagnetic resonance (EPR) and Saccharomyces cerevisiae studies indicated that the complexes were scavengers rather than reactive oxygen species promoters. Their DNA intercalating capacity was evidenced by modifications in both absorption and fluorescence spectra. Furthermore, both complexes exhibited nuclease-like activity, which increased in the presence of hydrogen peroxide. 相似文献
144.
Sattar R. Majeed Mina A. Amin Fawzy A. Attaby Marta E. Alberto Ahmed A. Soliman 《Molecules (Basel, Switzerland)》2022,27(3)
Three new palladium complexes ([Pd(DABA)Cl2], [Pd(CPDA)Cl2], and [Pd(HZPY)Cl2]) bearing dinitrogen ligands (DABA: 3,4-diaminobenzoic acid; CPDA: 4-chloro–o-phenylenediamine; HZPY: 2-hydraziniopyridine) were synthesized, characterized, and tested against breast cancer (MCF-7), prostate carcinoma cell line (PC3) and liver carcinoma cell line (HEPG2). [Pd(DABA)Cl2] complex exhibited the highest inhibition percentage, lying between 68–71%. The hydrolysis mechanism of each palladium complex, the key step preceding the binding to the biological target, as well as their photophysical properties were explored by means of DFT and TDDFT computations. Results indicate a faster hydrolysis process for the Pd(DABA)Cl2 complex. The computed activation energies for the first and second hydrolysis processes suggest that all the compounds could reach DNA in their monohydrated form. 相似文献
145.
My Hang V. Huynh Jennifer Smyth Modi Wetzler Brendan Mort Paul K. Gong Laura M. Witham Donald L. Jameson David K. Geiger Joanne M. Lasker Mina Charepoo Michelle Gornikiewicz Jose M. Cintron Gretchen Imahori Roberto R. Sanchez Amy C. Marschilok Lynn M. Krajkowski David G. Churchill Melvyn Rowen Churchill Kenneth J. Takeuchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2001,113(23):4601-4605
146.
Hossein Reza Darabi Marjan Azimzadeh Arani Mohsen Tafazzoli Mina Ghiasi 《Monatshefte für Chemie / Chemical Monthly》2008,139(10):1185-1189
The existence of a short C–H ⋯ π (alkyl–alkyne) interaction in the structure of a strained and relatively rigid tolanophane
is expected to hinder the rotation about the C–C sp3 single bond. Variable-temperature NMR experiments (performed in three solvents, CDCl3, THF-d8, and acetone-d6) and ab initio density functional calculations were carried out to investigate its dynamic nature. An energy barrier of 48.6 kJ/mol is determined
at coalescence (210 K) with acetone-d6 which is in good agreement with calculation result (54 kJ/mol).
Correspondence: Hossein Reza Darabi, Chemistry and Chemical Engineering Research Center of Iran, Pajoohesh Blvd., km 17, Karaj
Hwy, 14968-13151 Tehran, Iran. 相似文献
147.
148.
Mina Teicher 《Israel Journal of Mathematics》1987,57(1):49-67
Using combinatorial methods, we classify all birational morphisms blowingm ≦ 5 divisors down to a point. Those which do not factor through the blowing up of a point are treated in the body of the
paper, and the factorizable morphisms are computed in an appendix. The relevance of this classification to the determination
of the nature of the “general” toric morphism is discussed. 相似文献
149.
Nishiwaki N Ogihara T Takami T Tamura M Ariga M 《The Journal of organic chemistry》2004,69(24):8382-8386
beta-Nitroenamines having a formyl group at the beta-position behave as the synthetic equivalent of unstable nitromalonaldehyde, which is a useful synthon for syntheses of versatile nitro compounds. High solubility of the nitroenamines into general organic solvents enables us to conduct reactions in the organic media accompanied by easy experimental manipulations and considerable safety. When nitroenamines are treated with 1,2-bifunctional nucleophiles such as hydrazines, hydroxylamine and glycine ester, nitrated pyrazoles, isoxazole and pyrrole-2-carboxylate were readily prepared. This methodology was also applicable to guanidines and 1,2-diamines, leading to pyrimidines and 1,4-diazepines, respectively. 相似文献
150.
Mina Ouahman Najate Ben Sari-Zizi Guy Guelachvili Claude Alamichel 《Molecular physics》2013,111(6):1477-1488
The 22 K sub-bands, belonging to the v 1 + v ±1 6, v 3 + v ± 5 + 2v 0 6 and v 3 + v ±1 5 + 2v ±2 6 rovibrational bands of monoisotopic CH3 79Br, have been identified. An RMS standard deviation of about 0·020 cm-1 has been achieved by a least squares fit over 619 lines belonging to these 22 sub-bands. For this purpose, a model taking into account (a) anharmonic resonances between (i) v 1 + v ±1 6, and v 3 + v ±1 5 + 2v 0 6, (ii) v 1 + v ±1 6 and v 3 + v ?1 5 + 2v ±2 6 and (iii) v 3 + v ±1 5 + 2v 0 6 and v 2 + 2v 3 + v ±1 5 and (b) Coriolis resonances between the v 2 and v 5 modes, was used. 相似文献