[EN] COMPOUNDS, COMPOSITIONS, AND METHODS FOR MODULATING CALCIUM ION HOMEOSTASIS [FR] COMPOSÉS, COMPOSITIONS ET PROCÉDÉS DE MODULATION DE L'HOMÉOSTASIE DES IONS CALCIUM
Desymmetrizing reductive aldol cyclizations of enethioate derivatives of 1,3-diones catalyzed by a chiral copper hydride
作者:Jun Ou、Wing-Tak Wong、Pauline Chiu
DOI:10.1039/c2ob25206f
日期:——
A range of enethioate derivatives of 1,3-diones underwent reductive aldol cyclizations catalyzed by a chiral copper hydride generated in situ from 5 mol% TaniaPhos (SL-T001-1), 5 mol% Cu(OAc)2·H2O, 5 mol% bipyridine and 2.0 equiv. of PhSiH3, to furnish polycyclic β-hydroxythioester products bearing three newly established contiguous stereocenters, with >98 : 2 dr and in up to 94% yield and 98% ee.
Reductive aldol cyclizations of unsaturated thioester derivatives of 1,3-cyclopentanedione catalyzed by chiral copper hydrides
作者:Jun Ou、Wing-Tak Wong、Pauline Chiu
DOI:10.1016/j.tet.2011.07.057
日期:2012.4
and enantioselectivity (up to 90% ee). With the related indanedione enethioate derivatives, the reductive aldol cyclization could attain up to 96% ee. These results demonstrate that enethioates have a significantly different reactivity and selectivity profile compared to enoate derivatives in the copper-catalyzed reductive aldol cyclization.
Intramolecular Baylis−Hillman and Morita Reactions Using Unsaturated Thiol Ester Substrates Containing Enolizable Aldehydes
作者:Gary E. Keck、Dennie S. Welch
DOI:10.1021/ol026638s
日期:2002.10.1
[reaction: see text] Previously unknown intramolecular Baylis-Hillman and Morita reactions involving cyclization of an unsaturated thiolester onto a pendant aldehyde function are reported. These can be used successfully for the preparation of both cyclopentenols and cyclohexenols, but the results are very sensitive to substrate and precise reaction conditions.
Formal Synthesis of the Anti-Angiogenic Polyketide (−)-Borrelidin under Asymmetric Catalytic Control
作者:Ashoka V. R. Madduri、Adriaan J. Minnaard
DOI:10.1002/chem.201001284
日期:——
potent anti‐angiogenesis activity. This paper describes its formal totalsynthesis by the most efficient route to date. This modular approach takes optimal benefit of asymmetric catalysis and permits the synthesis of analogues; in addition, the high yields and selectivities obtained eliminate the need for separation of stereoisomers. The upper half of borrelidin has been accessed by iterative copper‐catalysed
An Iterative Catalytic Route to Enantiopure Deoxypropionate Subunits: Asymmetric Conjugate Addition of Grignard Reagents to α,β-Unsaturated Thioesters
作者:Renaud Des Mazery、Maddalena Pullez、Fernando López、Syuzanna R. Harutyunyan、Adriaan J. Minnaard、Ben L. Feringa
DOI:10.1021/ja053020f
日期:2005.7.1
A highly enantioselective (up to 96% ee) conjugate addition of Grignard reagents, in particular, MeMgBr, to alpha,beta-unsaturated thioesters is provided as well as its application to a diastereo- and enantioselective iterative route to syn- and anti-1,3-dimethyl arrays and deoxypropionate subunits. The versatility of the method is illustrated in the synthesis of (-)-lardolure, a multimethyl-branched