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91.
Yang T He H Ang W Yang YH Yang JZ Lin YN Yang HC Pi WY Li ZC Zhao YL Luo YF Wei Y 《Molecules (Basel, Switzerland)》2012,17(3):2351-2366
A series of N-3-substituted 7-aminopyrido[2,3-d]pyrimidin-6-carbonitrile derivatives was readily synthesized and their anti-proliferative activities on five types of tumor cells were evaluated through a cell-based phenotypic screening approach. Compound 3k was found to be potent on human colon cancer SW620 cells with an IC(50) value of 12.5 mM. Structural optimization of compound 3k led to compound 4a with improved anti-proliferative potency on SW620 cells with an IC(50) value of 6.9 mM. Further cell-cycle analyses suggested that compound 4a induced apoptosis of SW620 cells in a concentration-dependent manner. 相似文献
92.
Perez-Delgado Y Barroso JZ Garofalo LA Manzanares CE 《The journal of physical chemistry. A》2012,116(9):2071-2079
The vibrational overtone spectra of the acetylenic (Δυ = 4, 5) and methyl (Δυ = 5, 6) C-H stretch transitions of tert-butyl acetylene [(CH(3))(3)C-C≡C-H] were obtained using the phase shift cavity ring down (PS-CRD) technique at 295 K. The C-H stretch fundamental and overtone absorptions of the acetylenic (Δυ = 2 and 3) and methyl (Δυ = 2-4) C-H bonds have been obtained using a Fourier transform infrared and near-infrared spectrophotometer. Harmonic frequency ω(ν(1)) and anharmonicities x(ν(1)) and x(ν(1), ν(24)) are reported for the acetylenic C-H bond. Molecular orbital calculations of geometry and vibrational frequencies were performed. A harmonically coupled anharmonic oscillator (HCAO) model was used to determine the overtone energy levels and assign the absorption bands to vibrational transitions of methyl C-H bonds. Band strength values were obtained experimentally and compared with intensities calculated in terms of the HCAO model where only the C-H modes are considered. No adjustable parameters were used to get order of magnitude agreement with experimental intensities for all pure local mode C-H transitions. 相似文献
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Bai JZ Bian JG Chen GP Chen HF Chen SJ Chen SM Chen Y Chen YQ Chen YB Cheng BS Cui XZ Ding HL Ding WY Du ZZ Fan XL Fang J Gao CS Gao ML Gao SQ Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y He J He M Hu GY Hu T Hu XQ Huang DQ Huang T Huang YZ Jiang CH Jin S Jin Y Kang SH Ke ZJ Lai YF Lan HB Lang PF Li F Li J Li PQ Li Q Li RB Li W Li WD Li WG Li XH Li XN Lin SZ Liu HM Liu J Liu JH Liu Q Liu RG Liu Y Liu ZA Lu JG Luo SQ Luo Y Ma AM 《Physical review letters》1996,76(19):3502-3505
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