61449-01-2Relevant academic research and scientific papers
Straightforward transformation of isoxazoles into pyrazoles: renewed and improved
Sviridov, Sergey I.,Vasil'ev, Andrei A.,Shorshnev, Sergey V.
, p. 12195 - 12201 (2007)
Isoxazoles bearing alkyl or carbamoyl groups were transformed into the corresponding pyrazoles in high yields by the treatment with hydrazine in methanol in the presence of a hydrogenation catalyst, e.g., Raney nickel, at ambient temperature. For the synthesis of N-substituted pyrazoles, hydrogenolysis of isoxazole followed by the treatment with substituted hydrazine was required. 3(5)-Aryl- or acylamido-substituted isoxazoles are less suitable for such transformations.
Reductive ring opening of 3,5-bis(2-arylethenyl)isoxazoles with molybdenum hexacarbonyl: A novel route to symmetrical and unsymmetrical curcumin derivatives
Hahnvajanawong, Viwat,Thaima, Thanaphat,Tearavarich, Ruchanok,Theramongkol, Parinya
, p. 127 - 135 (2016/05/09)
Curcumin derivatives were successfully synthesized from 3,5-dimethylisoxazole by lateral metalation and condensation with various aromatic aldehydes sequentially at C5- and C3-methyl groups. After dehydration, further transformation of isoxazole ring to β-diketone moiety was accomplished by reductive ring opening using molybdenum hexacarbonyl [Mo(CO)6] and subsequent simple acidic hydrolysis.
Synthesis of optically active β'-hydroxy-β-enaminoketones via enzymatic resolution of carbinols derived from 3,5-disubstituted isoxazoles
Fuentes, Jose Antonio,Maestro, Alicia,Testera, Ana Ma,Banez, Jose Manuel
, p. 2565 - 2577 (2007/10/03)
The preparation of several enantiomerically pure β'-hydroxy-β-enaminoketones from the corresponding isoxazolic carbinols, which have been obtained by enzymatic kinetic resolution of the racemic β-hydroxyisoxazoles catalyzed by lipases, is described. The enzymatic transesterification of racemic (±)-5-(2-hydroxypropyl)-3-methylisoxazole 3a, and racemic (±)-5-(2-hydroxy-2-p-tolylethyl)-3-methylisoxazole 3d, has been studied with respect to the influence of experimental variables such as the used enzyme, the acylating agent or the solvent on the enantioselectivity of the reaction. After the reductive cleavage of the isoxazolic ring of the enantiopure carbinols, (R)- and (S)-2-amino-4-oxo-2-hepten-6-ol, (R)- and (S)-5, and (R)-2-amino-6-p-tolyl-4-oxo-2-hexen-6-ol, (R)-7 with an enantiomeric excess >98% were obtained. Copyright (C) 2000 Elsevier Science Ltd.
