- A one-pot synthesis of 5,5-disubstituted hydantoin derivatives using magnetic Fe3O4 nanoparticles as a reusable heterogeneous catalyst
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A facile and rapid method for the one-pot synthesis of 5,5-disubstituted hydantoins in the presence of magnetic Fe3O4 nanoparticles has been developed. The multicomponent reactions of carbonyl compounds (aldehydes and ketones), potassium cyanide and ammonium carbonate were carried out under solvent-free conditions to obtain various hydantoin derivatives. The magnetic catalyst could be readily separated by an external magnet from the reaction mixture. This procedure has many advantages, such as the use of a reusable magnetic catalyst, high yields, short reaction times, simplicity and very easiness with implementing the methodology.
- Safari, Javad,Javadian, Leila
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p. 1165 - 1171
(2013/12/04)
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- Potent and specific inhibition of human leukocyte elastase, cathepsin G and proteinase 3 by sulfone derivatives employing the 1,2,5-thiadiazolidin-3-one 1,1 dioxide scaffold
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This paper describes the results of structure-activity relationship studies in a series of heterocyclic mechanism-based inhibitors based on the 1,2,5-thiadiazolidin-3-one 1,1 dioxide scaffold I and capable of interacting with the S(n) and S(n)' subsites of a serine proteinase. Sulfone derivatives of I were found to be highly effective, time-dependent inhibitors of human leukocyte elastase (HLE), cathepsin G (Cat G) and proteinase 3 (PR 3). The judicious selection of an R1 group (accommodated at the primary specificity site S1) that is based on the known substrate specificity of a target serine proteinase, was found to yield highly selective inhibitors. The presence of a benzyl group (R2=benzyl) at the S2 subsite was found to lead to a pronounced enhancement in inhibitory potency. Furthermore, the effective use of computer graphics and modeling has led to the design of potent, water-soluble inhibitors. The results of these studies demonstrate that the 1,2,5-thiadiazolidin-3-one 1,1, dioxide platform provides an effective means for appending recognition elements in a well-defined vector relationship, and in fashioning highly-selective and potent inhibitors of serine proteinases. Copyright (C) 1998 Elsevier Science Ltd.
- Groutas, William C.,Kuang, Rongze,Ruan, Sumei,Epp, Jeffrey B.,Venkataraman, Radhika,Truong, Tien M.
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p. 661 - 671
(2007/10/03)
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- Preparation of α-aminothioamides from aldehydes
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The conversion of aldehydes into α-aminonitriles and thence into imidazolidin-4-thiones has been studied.Hydrolysis of the appropriate imidazolidin-4-thiones gave thioamides of nine naturally occuring α-amino acids.The possible pre-biotic significance of these compounds is discussed.
- Paventi, Martino,Edward, John T.
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p. 282 - 289
(2007/10/02)
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