43003-15-2Relevant academic research and scientific papers
Efficient and Flexible Synthesis of Highly Functionalised 4-Aminooxazoles by a Gold-Catalysed Intermolecular Formal [3+2] Dipolar Cycloaddition
Gillie, Andrew D.,Jannapu Reddy, Raju,Davies, Paul W.
supporting information, p. 226 - 239 (2016/02/14)
Oxazoles are important motifs within bioactive and functional materials. Complex, fully substituted and functionalised 4-aminooxazoles are accessed by an efficient intermolecular reaction between an ynamide and an N-acylpyridinium N-aminide in the presence of a gold catalyst. The formal [3+2] dipolar cycloaddition employs a nucleophilic nitrenoid approach to access the 1,3-N,O-dipole character in a controllable fashion. The selectivity for a cycloaddition pathway provides a stark contrast against the indiscriminate reactivity of electrophilic acyl nitrenes. Protocols for the formation of acyl-functionalised aminides are reported from accessible precursors including carboxylic esters and acids. The function of these aminides in the oxazole-forming reaction has been explored and it is shown that substantial elaboration is accommodated despite proximity to the reactive centre. As a result functional oxazole-based motifs, such as chiral oxazoles with biologically pertinent substitution patterns, are readily accessible. The use of ynamide types that are unexplored or little used in gold catalysis has been evaluated. Unusual all-heteroatom substitution patterns around the oxazole are shown to be accessible using thio-ynamides. The study shows that a close stoichiometry of reactants is suitable alongside relatively low loadings of the bench-stable precatalysts in practically straightforward multi-mmol scale reactions. The efficiency and flexibility of this regioselective intermolecular preparation is demonstrated in the ready synthesis of oxazoles with substantial structural and functional group variation.
Synthesis and antimuscarinic activity of some N-(4-dimethylaminomethyl- 2-phenyl-[1,3]dioxolan-2-ylmethyl)lactam methiodides
Malmusi, Luca,Franchini, Silvia,Mucci, Adele,Angeli, Piero,Gulini, Ugo,Marucci, Gabriella,Brasili, Livio
, p. 499 - 509 (2007/10/03)
A series of 1,3-dioxolane-based ligands, having a lactam function were synthesized and tested as potential muscarinic antagonists. The compounds display moderate affinity for the three receptor subtypes M1-M3, with significant selectivity for the M1-M3 over the M2 subtype.
α-Nitrogenated organolithium compounds from α-amidomethyl and α-aminomethyl sulfones
Alonso, Diego A.,Alonso, Emma,Najera, Carmen,Ramon, Diego J.,Yus, Miguel
, p. 4835 - 4856 (2007/10/03)
Successive reaction of α-amidomethyl sulfones 7a,b, derived from primary amides, with n-butyllithium and primary alkyl bromides (CH2 = CHCH2Br, CH2 = CMeCH2Br, CH2 = CBrCH2Br, CH ≡ CCH
α-Nitrogenated organolithium compounds from N-(tosylmethyl)amides
Alonso, Diego A.,Alonso, Emma,Nájera, Carmen,Yus, Miguel
, p. 491 - 492 (2007/10/03)
Deprotonation of α-amido sulfones 7 with BunLi at -90°C followed by reaction with electrophiles leads, depending on the substitution on the amidic nitrogen to enamides 10 (secondary amides 7a,b) or functionalised α-amido sulfones 12 (tertiary amides 7c,d). Naphthalene-catalysed lithiation of tertiary α-amido sulfones 7c,d in the presence of electrophiles (Barbier conditions) at -78°C affords functionalised amides 13.
Hydroxylations microbiologiques de pyrrolidinones-2 (note de laboratoire)
Srairi, Driss,Maurey, Georges
, p. 297 - 301 (2007/10/02)
Microbial hydroxylations of various pyrrolidin-2 ones, especially N-acylated, with Beauveria sulfurescens have been carried out.The regioselectivity depends on the nature of the substituent on the nitrogen atom and the hydroxylation may occur at position 3,4 or 5 of the heterocycle.Hydroxylations at position 3 or 4 occur with low enantioselectivity.
