3984-53-0Relevant articles and documents
Investigation of carbon-2 substituted imidazoles and their corresponding ionic liquids
Liao, Chen,Zhu, Xiang,Sun, Xiao-Guang,Dai, Sheng
supporting information; experimental part, p. 5308 - 5310 (2011/10/30)
The functionality at the C-2 position of the imidazole ring plays a key role in defining the chemical properties of the imidazoles and their corresponding ionic liquids. Imidazoles 1-6 with different C-2 functionality were synthesized and their corresponding ionic liquids were systematically investigated. Based on their physical properties the six imidazoles can be divided into three groups. (1) The imidazoles 2 and 3 are capable of self-polymerization to form poly(ionic liquid)s, and they are characterized with a strong leaving group at the C-2 position. (2) The imidazoles 4 and 5 can form ionic liquids, but they are very sensitive to moisture. (3) The imidazoles 1 and 6 can form stable ionic liquids, and their stabilities were influenced by the electronic effects of the substituents at the C-2 position.
A direct synthetic approach to novel quadrupolar [14]azolophanes
Alcalde, Ermitas,Alemany, Montserrat,Gisbert, Maria
, p. 15171 - 15188 (2007/10/03)
A convergent '3+1' synthesis allowed a simple entrance to the first examples of [14]metaazolophanes 1 and [14l(meta-ortho)2azolophanes 2 built up from heterocyclic betaine subunits, illustrating a prototype of phanes constructed by both highly π-excessiveand highly π-deficient heteroaromatic moieties linked in a 1,3-alternating fashion.
Phosphotriesters Approach to the Synthesis of Oligonucleotides: A Reappraisal
Reese, Colin B.,Pei-Zhuo, Zhang
, p. 2291 - 2302 (2007/10/02)
The phosphotriester approach to the synthesis of oligodeoxyribo- and oligoribo-nucleotides in solution has been reinvestigated.The efficacy of mesitylene-2-sulfonyl chloride (MSCl) 15a, 2,4,6-triisopropylbenzenesulfonyl chloride (TrisCl) 15b, 4-bromobenzenesulfonyl chloride 15c, naphthalene-1-sulfonyl chloride 39, and 2- and 4-nitrobenzenesulfonyl chlorides 40a and 40b, respectively, as activating agents has been examined.The latter arenesulfonyl chlorides have been used in conjunction with the following nucleophilic catalysts: 1-methylimidazole, 3-nitro-1H-1,2,4-triazole 19, 5-(3-nitrophenyl)-1H-tetrazole 20a, 5-(3,5-dinitrophenyl)-1H-tetrazole 20b, 5-(1-methylimidazol-2-yl)-1H-tetrazole 21, 5--1H-tetrazole 22, 4-ethoxypyridine 1-oxide 14a, 4,6-dinitro-1-hydroxybenzotriazole 29a, 1-hydroxy-4-nitro-6-(trifluoromethyl)benzotriazole 29b, 1-hydroxy-5-phenyltetrazole 30a and 1-hydroxy-5-(3-nitrophenyl)tetrazole 30b.The rates of formation and yields of the fully protected dideoxyribonucleoside and diribonucleoside phosphates 37 and 47, respectively, were determined using various combinations of activating agents and nucleophilic catalysts.Although 2- and 4-nitrobenzenesulfonyl chlorides 40a and 40b, respectively, proved to be the most powerful activating agents, their use in the deoxy-series led to the formation of by-products and hence to unsatisfactory isolated yields of the dideoxyribonucleoside phosphate 37.
Substituted thiazoles as immunoregulants
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, (2008/06/13)
Thiazole derivatives have been made, for example, by reacting a 2-aryl-2,2-dialkoxyethylamine with an appropriately substituted aryl acetyl halide followed by treating the resulting amide with diphosphoryl pentasulfide. The thiazole derivatives are found to be effective immunoregulants.
