140840-39-7Relevant academic research and scientific papers
Practical Synthesis of Enantiomerically Pure myo-Inositol Derivatives
Bruzik, Karol S.,Myers, Jeffrey,Tsai, Ming-Daw
, p. 1009 - 1012 (1992)
The synthesis of enantiomerically pure myo-inositol derivatives is accomplished using a mandelic acid-derived acyl protecting group.
Synthesis of 4-quinolones via cyclocondensation of substituted ortho-amidoacetophenones: A refit to the camps cyclization by applying trimethylsilyl trifluoromethanesulfonate/triethylamine
Eidamshaus, Christian,Triemer, Therese,Reissig, Hans-Ulrich
, p. 3261 - 3266 (2011/11/30)
A modification of the classical Camps cyclization is described. A series of substituted 4-quinolone derivatives is prepared via trimethylsilyl trifluoromethanesulfonate/triethylamine induced cyclocondensation of substituted ortho-amidoacetophenones. The process shows a broad substrate scope and allows selective preparation of 2-aryl- and 2-alkyl-substituted 4-quino-lones. Enantiopure starting materials react without loss of optical purity using the modified conditions. Subsequent transformations of the products involving preparation of a 4-quinolyl nonaflate and O-selective methylation are also described. Georg Thieme Verlag Stuttgart · New York.
A chiral pool strategy for the synthesis of enantiopure hydroxymethyl-substituted pyridine derivatives
Eidamshaus, Christian,Reissig, Hans-Ulrich
, p. 6056 - 6069 (2011/12/15)
A simple procedure for the synthesis of enantiopure hydroxymethyl- substituted pyridine derivatives is presented. The developed method is based on TMSOTf-promoted cyclocondensations of β-ketoenamides, leading to differently substituted 4-hydroxypyridine/4-pyridone derivatives. The required β-ketoenamides were prepared by acylation ofeasily available enamino ketones with suitably protected enantiopure carboxylic chlorides. Most of the experiments were performed with D-mandelic acid as starting material. It has been shown that all steps occur essentially without racemisation. Several of the prepared 4-pyridone derivatives were transformed into the corresponding pyrid-4-yl nonaflates and subjected to a series of palladium-catalysed transformations, such as Suzuki, Heck or Sonogashira reactions. In addition, regioselective side-chain functionalisation of unsymmetrically 2,6-disubstituted pyridine derivatives was accomplished by application of Boekelheide rearrangements of the corresponding pyridine N-oxides. The presented methods allow a flexible, rapid and scalable approach to highly substituted, enantiopure pyridine derivatives. A new route to hydroxymethyl-substituted pyridine derivatives, starting from enantiopure α-hydroxy carboxylic acids, is described. The synthetic value of the method is demonstrated by multifaceted functionalisation reactions of the prepared pyridine derivatives, leading to a series of highly substituted enantiopure pyridine derivatives.
Serendipitous discovery of α-hydroxyalkyl esters as β-lactamase substrates
Pelto, Ryan B.,Pratt
experimental part, p. 10496 - 10506 (2011/10/18)
O-(1-Carboxy-1-alkyloxycarbonyl) hydroxamates were found to spontaneously decarboxylate in aqueous neutral buffer to form O-(2-hydroxyalkylcarbonyl) hydroxamates. While the former molecules do not react rapidly with serine β-lactamases, the latter are quite good substrates of representative class A and C, but not D, enzymes, and particularly of a class C enzyme. The enzymes catalyze hydrolysis of these compounds to a mixture of the α-hydroxy acid and hydroxamate. Analogous compounds containing aryloxy leaving groups rather that hydroxamates are also substrates. Structure-activity experiments showed that the α-hydroxyl group was required for any substantial substrate activity. Although both d- and l-α-hydroxy acid derivatives were substrates, the former were preferred. The response of the class C activity to pH and to alternative nucleophiles (methanol and d-phenylalanine) suggested that the same active site functional groups participated in catalysis as for classical substrates. Molecular modeling was employed to explore how the α-hydroxy group might interact with the class C β-lactamase active site. Incorporation of the α-hydroxyalkyl moiety into novel inhibitors will be of considerable interest.
