627-32-7Relevant articles and documents
A "clickable" styryl dye for fluorescent DNA labeling by excitonic and energy transfer interactions
Rubner, Moritz M.,Holzhauser, Carolin,Bohlaender, Peggy R.,Wagenknecht, Hans-Achim
, p. 1299 - 1302 (2012)
In conclusion, we have shown that the CyIQ dye represents a promising covalently attached fluorescent label for DNA, since it shows good brightness and excellent photostability. In particular, the photochemical stability of CyIQ is significantly enhanced compared to the routinely applied fluoresceine. The dye is "clickable", that means it can be incorporated postsynthetically and therefore easily into oligonucleotides by using the cycloaddition between azides and acetylenes. In this study, the "click" reaction was performed representatively to 2'-propargylated uridines in DNA. This structural approach has the advantage that the preference for pairing between the modified uridine and adenine in the counterstrand is potentially maintained and thereby the DNA duplex conformation stays stable.[9a] One could envision that this experimentally simple labeling method can be extended to other acetylene-containing building blocks in RNA and DNA, which are either commercially or synthetically available. Beside the application as single internal DNA marker, the CyIQ label can be combined with itself and TR, all chromophors adjacent to each other as intra-strand fluorophore pairs. Excitonic interactions between the CyIQ dyes and energy transfer interactions between CyIQ and thiazole red provide interesting alternatives for fluorescence readouts for DNA hybridization, which are either fluorescence enhancement or fluorescence color change, respectively.
CO2 triggering and controlling orthogonally multiresponsive photochromic systems
Darwish, Tamim A.,Evans, Richard A.,James, Michael,Malic, Nino,Triani, Gerry,Hanley, Tracey L.
, p. 10748 - 10755 (2010)
We report a new generic method of reversibly controlling the photochromism of spiropyrans. It was found that the photochromic effect of spiropyrans can be reversibly switched on and off by addition and removal of carbon dioxide (CO2) to spiropyran in alcohol solutions containing an amidine (i.e., DBU) that acts as a CO2 sensitizer. Spiropyrans are not photochromic in the presence of DBU but photochromic when CO2 is subsequently added to the solution. The CO2 is readily removed by inert gas bubbling, thus allowing facile activation and deactivation of the photochromic effect. Carbon dioxide, without the presence of the sensitizing amidine, had no effect on photochromism of the spiropyrans. Other photochromic dyes classes such as spirooxazines and chromenes are not affected by this CO2/DBU stimulus. As a result, orthogonal activation of mixtures of spirooxazines and spiropyrans was achieved to provide four color states (clear, yellow, green, and blue) by varying the combinations of the stimuli of UV, visible light, CO 2, and CO2 depleted. This finding now permits the many applications using spiropyrans to be CO2 responsive.
Total Synthesis of Phenanthropiperidine Alkaloids by Sequential Alkylation of N,N-Dibenzylaminoacetonitrile
Bouvry, Christelle,Cupif, Jean-Fran?ois,Franzetti, Milène,Hurvois, Jean-Pierre
, p. 6037 - 6051 (2021/12/10)
Two representative members of the phenanthropiperidine alkaloid family, tylophorine (1) and cryptopleurine (2), were synthesized by a bidirectional alkylation strategy employing dibenzylaminoacetonitrile as a substrate. This approach relies on the unprecedented condensation of metallated α-aminonitriles with bromomethylphenanthrenes to provide fully substituted α-aminonitriles, which are subjected to a NaBH4-mediated reductive decyanation process to form homobenzylic amines. From these intermediates, a terminal leaving group was introduced by simple chemical manipulation, and its displacement by a free primary amine under two favorable cyclization processes led to the formation of the future E-ring of both alkaloids in high yields. Finally, a late Pictet-Spengler cyclization ensured the formation of a D-ring for the alkaloids 1 and 2.
Rhodium-Catalyzed Generation of Anhydrous Hydrogen Iodide: An Effective Method for the Preparation of Iodoalkanes
Zeng, Chaoyuan,Shen, Guoli,Yang, Fan,Chen, Jingchao,Zhang, Xuexin,Gu, Cuiping,Zhou, Yongyun,Fan, Baomin
, p. 6859 - 6862 (2018/10/25)
The preparation of anhydrous hydrogen iodide directly from molecular hydrogen and iodine using a rhodium catalyst is reported for the first time. The anhydrous hydrogen iodide generated was proven to be highly active in the transformations of alkenes, phenyl aldehydes, alcohols, and cyclic ethers to the corresponding iodoalkanes. Therefore, the present methodology not only has provided convenient access to anhydrous hydrogen iodide but also offers a practical preparation method for various iodoalkanes in excellent atom economy.
Development of indazolylpyrimidine derivatives as high-affine EphB4 receptor ligands and potential PET radiotracers
Ebert, Kristin,Wiemer, Jens,Caballero, Julio,K?ckerling, Martin,Steinbach, J?rg,Pietzsch, Jens,Mamat, Constantin
, p. 6025 - 6035 (2015/11/10)
Due to their essential role in the pathogenesis of cancer, members of the Eph (erythropoietin-producing hepatoma cell line-A2) receptor tyrosine kinase family represent promising candidates for molecular imaging. Thus, the development and preparation of novel radiotracers for the noninvasive imaging of the EphB4 receptor via positron emission tomography (PET) is described. First in silico investigations with the indazolylpyrimidine lead compound which is known to be highly affine to EphB4 were executed to identify favorable labeling positions for an introduction of fluorine-18 to retain the affinity. Based on this, reference compounds as well as precursors were developed and labeled with carbon-11 and fluorine-18, respectively. For this purpose, a protecting group strategy essentially had to be generated to prevent unwanted methylation and to enable the introduction of fluorine-18. Further, a convenient radiolabeling strategy using [11C]methyl iodide was established which afforded the isotopically labeled radiotracer in 30-35% RCY (d.c.) which is identical with the original inhibitor molecule. A spiro ammonium precursor was prepared for radiolabeling with fluorine-18. Unfortunately, the labeling did not lead to the desired 18F-radiotracer under the chosen conditions.