Synthesis and Identification of Small Molecules that Potently Induce Apoptosis in Melanoma Cells through G1 Cell Cycle Arrest
摘要:
Late-stage malignant melanoma is a cancer that is refractory to current chemotherapeutic treatments. The average survival time for patients with such a diagnosis is 6 months. In general, the vast majority of anticancer drugs operate through induction of cell cycle arrest and cell death in either the DNA synthesis (S) or mitosis (M) phase of the cell cycle. Unfortunately, the same mechanisms that melanocytes possess to protect cells from DNA damage often confer resistance to drugs that derive their toxicity from S or M phase arrest. Described herein is the synthesis of a combinatorial library of potential proapoptotic agents and the subsequent identification of a class of small molecules (triphenyl methylamides, TPMAs) that arrest the growth of melanoma cells in the G1 phase of the cell cycle. Several of these TPMAs are quite potent inducers of apoptotic death in melanoma cell lines (IC50 similar to 0.5 mu M), and importantly, some TPMAs are comparatively nontoxic to normal cells isolated from the bone marrow of healthy donors. Furthermore, the TPMAs were found to dramatically reduce the level of active nuclear factor kappa-B (NF kappa B) in the cell; NF kappa B is known to be constitutively active in melanoma, and this activity is critical for the proliferation of melanoma cells and their evasion of apoptosis. Compounds that reduce the level of NF kappa B and arrest cells in the G1 phase of the cell cycle can provide insights into the biology of melanoma and may be effective antimelanoma agents.
Amine Activation:<i>N</i>-Arylamino Acid Amide Synthesis from Isothioureas and Amino Acids
作者:Yan-Ping Zhu、Pieter Mampuys、Sergey Sergeyev、Steven Ballet、Bert U. W. Maes
DOI:10.1002/adsc.201700134
日期:2017.7.17
functional group compatibility, with respect to side chain functionality of the amino acid (e. g. aliphatic and aromatic OH, (hetero)aromatic NH, amide NH, thioether), and the chiral amino acids do not undergo epimerization. The mechanism of the new amidesynthesis has been studied.
Nickel-Catalyzed Reductive Addition of Aryl/Benzyl Halides and Pseudohalides to Carbodiimides for the Synthesis of Amides
作者:Farhad Panahi、Fereshteh Jamedi、Nasser Iranpoor
DOI:10.1002/ejoc.201501349
日期:2016.2
A Nickel-catalyzed reductive process is described for the directamidation of benzyl and aryl halides using carbodiimides as the amidating agent. Moreover, aryl and benzyl C–O electrophiles such as triflate, acetate, tosylate, trityl ether, and pivalate were converted into amides using this method. The in-situ-generated Ni0 acts as a catalyst for the reaction at room temperature for benzylic substrates
Indifference to Hydrogen Bonding in a Family of Secondary Amides
作者:D. Tyler McQuade、Sonya L. McKay、Douglas R. Powell、Samuel H. Gellman
DOI:10.1021/ja9711019
日期:1997.9.1
N-H stretch region IR spectroscopy has been used to probe the hydrogen bond-donating properties of six structurally related secondary amides in which the amide group is flanked by sterically bulky groups. For three of the compounds, solid state IR analysis reveals N-R stretch bands >3400 cm(-1), which suggests the absence of intermolecular N-H-O=C hydrogen bonds. Crystallographic data for these three amides confirm the absence of a standard N-H-O=C interaction. For the other three amides, N-H stretch bands in the range 3370-3290 cm(-1) suggest the occurrence of intermolecular N-H-O=C hydrogen bonds in the solid state, but high quality crystals could not be grown. Steric hindrance to hydrogen bond donation by these amides is manifested in IR data obtained in DMSO: although this solvent is a strong hydrogen bond acceptor, N-H stretch bands are observed for both solvent-hydrogen bonded and non-hydrogen bonded amide groups. The amides described here and related compounds should be useful for calibrating spectroscopic methods that are intended to detect hydrogen bond formation.