[EN] NOVEL PEROXIDE DERIVATIVES, THEIR PROCESS OF PREPARATION AND THEIR USE IN HUMAN MEDICINE AND IN COSMETICS FOR THE TREATMENT OR PREVENTION OF ACNE [FR] NOUVEAUX DÉRIVÉS DE PEROXYDE, LEUR PROCÉDÉ DE PRÉPARATION ET LEUR UTILISATION EN MÉDECINE HUMAINE ET DANS DES COSMÉTIQUES POUR LE TRAITEMENT OU LA PRÉVENTION DE L'ACNÉ
A Mild Anionic Method for Generating <i>o-</i>Quinone Methides: Facile Preparations of <i>Ortho</i>-Functionalized Phenols
作者:Ryan M. Jones、Ryan W. Van De Water、Christopher C. Lindsey、Christophe Hoarau、Thay Ung、Thomas R. R. Pettus
DOI:10.1021/jo001752e
日期:2001.5.1
A low-temperature method for generating o-quinone methides is described which permits facile introduction of assorted R substituents onto the aryl ring system at low temperature. The method is useful for the efficient preparation of ortho-ring-alkylated phenols.
Organocatalytic Methods for Chemoselective <i>O</i>-<i>tert</i>-Butoxycarbonylation of Phenols and Their Regeneration from the <i>O</i>-<i>t</i>-Boc Derivatives
作者:Sunay V. Chankeshwara、Rajesh Chebolu、Asit K. Chakraborti
DOI:10.1021/jo8013325
日期:2008.11.7
without any side reactions (bromination, addition of CBr3 to a double bond, and formation of symmetrical diaryl carbonates, cycliccarbonates, or carbonic-carbonic anhydrides). The parent phenols are regenerated from the O-t-Boc derivatives by the catalyst system CBr4-PPh3 without affecting other protecting groups (aryl alkyl ether, alkyl ester, and thioacetal) or competitive side reaction such as bromination
Oxyphosphonium Enolate Equilibria in a (4+1)‐Cycloaddition Approach toward Quaternary C3‐Spirooxindole Assembly
作者:Eva M. Gulotty、Kevin X. Rodriguez、Erin E. Parker、Brandon L. Ashfeld
DOI:10.1002/chem.202100355
日期:2021.7.16
convergent (4+1)-cycloaddition strategy toward the construction of spirooxindole benzofurans that involves the intermediacy of an isatin-derived oxyphosphonium enolate is presented. Mechanistic investigations employing in situ NMR analysis of the reaction mixture revealed a correlation between phosphonium enolate structure and product distribution that was heavily influenced by the solvent and reaction temperature
The present invention is a method for synthesizing furanosteroids. The method involves intramolecular Diels-Alder/retro-Diels-Alder reaction and tautomerization of a functionalized alkyne oxazole to produce a furo[2,3-b]phenol derivative which is elaborated by intermolecular and intramolecular condensations to generate ring-A of the furanosteroid. Furanosteroids and pharmaceutical compositions containing the same are also provided.
Chemoselective synthesis of tetrasubstituted furans via intramolecular Wittig reactions: mechanism and theoretical analysis
作者:Yu-Ting Lee、Yen-Te Lee、Chia-Jui Lee、Chia-Ning Sheu、Bo-Yu Lin、Jeng-Han Wang、Wenwei Lin
DOI:10.1039/c3ob40858b
日期:——
An efficientsynthesis of tetrasubstitutedfurans was achieved from the corresponding α,β-unsaturated ketone derivatives, acid chlorides, and Bu3P in the presence of Et3N via a chemoselective intramolecular Wittig reaction as the key step. The presence of an additional electron-withdrawing group in the α-position of Michael acceptors controlled the chemoselectivities of presumable phosphorus ylides