191330-98-0Relevant articles and documents
Efficient construction of polycyclic alkaloid synthetic precursors by a xanthate free radical addition and Mannich cyclisation cascade
Tate, Edward W.,Zard, Samir Z.
, p. 4683 - 4686 (2002)
Routes to synthetic precursors of Lupin and Eburna alkaloids have been developed, featuring the rapid construction of highly functionalised intermediates by the intermolecular radical coupling of xanthates and alkenes, followed by acid-mediated condensation-cyclisation.
Synthetic approach to gain insight into antigenic determinants of cephalosporins: In vitro studies of chemical structure-IgE molecular recognition relationships
Montanez, Maria Isabel,Mayorga, Cristobalina,Torres, Maria Jose,Ariza, Adriana,Blanca, Miguel,Perez-Inestrosa, Ezequiel
scheme or table, p. 706 - 717 (2012/03/11)
Cephalosporins, after penicillins, are the most widely used antibacterial agents in infectious diseases and the cause of adverse immune reactions in the world. Whether a patient with a suspected allergy to a β-lactam can safely take a cephalosporin is often a matter of debate. However, there are no tests with enough sensitivity to detect allergy to cephalosporins. Understanding the way in which the drug metabolizes after protein conjugation is important if we are to make advances in the diagnosis of clinical allergy. Structural studies of cephalosporin-protein adducts have never been addressed successfully and are difficult to investigate. Our approach to determine the requirements involved in antigenic determinant structures consisted of designing and synthesizing a proposed skeleton that remains linked to the carrier protein after chemical degradation in cephalosporin conjugated to carrier proteins. In this study, a series of proposed epitopes were efficiently synthesized following a versatile methodology, involving the condensation of the R1 acyl side chains of native cephalosporins, with the nuclear fragment structures (derived from amino acids or other aminofunctionalized molecules). The final well-defined structures 1-4 (a-f), representing a fragment from the proposed cephalosporin-Lys(protein) adduct intermediate, consist of closely related low-molecular-weight molecules, differing only in the functional group at C-3 and the R1 side chains. They were assessed with sera from patients allergic to cephalosporins to study structure-IgE molecular recognition relationships. These IgE showed an enhanced recognition to proposed new skeleton epitopes with adequate functionality at C-3, with the specifities mainly related to the R1 acyl side chain. Thus, this study led us to refine the model haptenic structures of cephalosporins and gain insight into the chemical mechanism of epitope formation.
Novel methods for the synthesis of 5-substituted-3-carboxy-2,5- and 4,5-dihydrothiophenes and 5-substituted 2- and 3-sulfolenes
Wilkinson, James A.,Ardes-Guisot, Nicolas,Ducki, Sylvie,Leonard, John
, p. 1065 - 1073 (2007/10/03)
Various approaches to the syntheses of 5-substituted-3-carbomethoxy-2,5-dihydrothiophenes and their product sulfolenes, required as synthetic precursors for tangutorine, are described. An efficient route to 3,5-disubstituted-4,5-dihydrothiophenes and henc
Towards the total synthesis of tangutorine by intramolecular Diels-Alder reaction
Wilkinson, James A.,Ardes-Guisot, Nicolas,Ducki, Sylvie,Leonard, John
, p. 8053 - 8056 (2007/10/03)
The syntheses of 3,5-disubstituted-2-sulfolenes, and their participation in Pictet-Spengler reactions to give precursors of tangutorine, are described.
A chemoselective, acid mediated conversion of amide acetal to oxazole: The key step in the synthesis of cardiovascular drug, ifetroban sodium
Swaminathan, Shankar,Singh, Ambarish K.,Li, Wen-Sen,Venit, John J.,Natalie Jr., Kenneth J.,Simpson, James H.,Weaver, Raymond E.,Silverberg, Lee J.
, p. 4769 - 4772 (2007/10/03)
The cyclization of acetal amide was carried out with trimethylsilyl trifluoromethanesulfonate, followed by elimination using sodium methoxide to give 2,5-disubstituted oxazole, thus completing a new route to the cardiovascular drug ifetroban sodium.