54986-94-6Relevant articles and documents
Single-step microwave-mediated synthesis of oxazoles and thiazoles from 3-oxetanone: A synthetic and computational study
Orr, David,Tolfrey, Alexandra,Percy, Jonathan M.,Frieman, Joanna,Harrison, Zo? A.,Campbell-Crawford, Matthew,Patel, Vipulkumar K.
, p. 9655 - 9662 (2013/07/26)
The direct microwave-mediated condensation between 3-oxetanone and primary amides and thioamides has delivered moderate to good yields of (hydroxymethyl)oxazoles and (hydroxymethyl)thiazoles. The reactions use a sustainable solvent and only require short reaction times. These are highly competitive methods for the construction of two classes of valuable heteroarenes, which bear a useful locus for further elaboration. Electronic structure calculations have shown that the order of events involves chalcogen atom attack at sp3 carbon and alkyl-oxygen cleavage. The critical role of acid catalysis was shown clearly, and the importance of acid strength was demonstrated. The calculated barriers were also fully consistent with the observed order of thioamide and amide reactivity. Spontaneous ring opening involves a modest degree of C-O cleavage, moderating the extent of strain relief. On the acid-catalysed pathway, C-O cleavage is less extensive still, but proton transfer to the nucleofuge is well advanced with the carboxylic acid catalysts, and essentially complete with methanesulfonic acid. Open sesame: The direct microwave-mediated condensation between 3-oxetanone and primary amides and thioamides has delivered moderate to good yields of oxazoles and thiazoles. The reactions use a sustainable solvent, require only short reaction times and represent a highly competitive method for the construction of two classes of valuable heteroarenes. Electronic structure calculations have been used to probe a range of potential reaction mechanisms (see figure). Copyright
Erythromycin derivatives with antibiotic activity
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, (2008/06/13)
Erythromycin derivatives with antibiotic activity and pharmaceutically acceptable salts thereof. A process for preparing such erythromycin derivatives and pharmaceutical compositions containing them as the active principle.
Heterocyclic compounds, their production and use
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, (2008/06/13)
Heterocyclic compounds represented by the general formula (I) wherein R stands for an optionally substituted aromatic heterocyclic group; X stands for oxygen atom, an optionally oxidated sulfur atom, —C(═O)— or —CH(OH)—; Y stands for CH or N; m denotes an integer of 0 to 10: n denotes an integer of 1 to 5: cyclic group ?stands for an optionally substituted aromatic azole group; and ring A is optionally further substituted, or salts thereof. The compound (I) possesses action of inhibiting tyrosine kinase and useful as antitumor agents.