Rhodium-catalyzed denitrogenative thioacetalization of N-sulfonyl-1,2,3-triazoles with disulfides: an entry to diverse transformation of terminal alkynes
A Transition-Metal-Free and Base-Mediated Carbene Insertion into Sulfur-Sulfur and Selenium-Selenium Bonds: An Easy Access to Thio- and Selenoacetals
作者:Dhanarajan Arunprasath、Govindasamy Sekar
DOI:10.1002/adsc.201600855
日期:2017.2.20
A transition‐metal‐free and base‐mediated carbene insertion across sulfur‐sulfur and selenium‐selenium bonds has been developed by employing N‐tosylhydrazone as a stable and safe carbene precursor. The ylide formation from carbene followed by Stevens rearrangement are considered to be the key steps. This thiol and selenol‐free protocol delivers thioacetals and selenoacetals in good to excellent yields
Cerium Triflate: An Efficient and Recyclable Catalyst for Chemoselective Thioacetalization of Carbonyl Compounds under Solvent-Free Conditions
作者:Anil Kumar、M. Sudershan Rao、V. Kameshwara Rao
DOI:10.1071/ch09296
日期:——
A simple and efficient chemoselectivethioacetalization of carbonylcompounds has been achieved using Ce(OTf)3 (10 mol-%) as a catalystunder solvent-free conditions. Advantages of the methodology include very short reaction times, excellent yields, the catalytic use of a water tolerant Lewis acid, and simple recovery and reuse of the catalyst.
Dioxabicyclooctanyl Naphthalenenitriles as Nonredox 5-Lipoxygenase Inhibitors: Structure−Activity Relationship Study Directed toward the Improvement of Metabolic Stability
作者:Daniel Delorme、Yves Ducharme、Christine Brideau、Chi-Chung Chan、Nathalie Chauret、Sylvie Desmarais、Daniel Dubé,、Jean-Pierre Falgueyret、Réjean Fortin、Jocelyne Guay、Pierre Hamel、Tom R. Jones、Carole Lépine、Chun Li、Malia McAuliffe、Cyril S. McFarlane、Deborah A. Nicoll-Griffith、Denis Riendeau、James A. Yergey、Yves Girard
DOI:10.1021/jm960301c
日期:1996.1.1
Naphthalenic lignan lactone 3a (L-702,539), a potent and selective 5-lipoxygenase (5-LO) inhibitor, is extensively metabolized at two different sites: the tetrahydropyran and the lactone rings. Early knowledge of the metabolic pathways triggered and directed a structure-activity relationship study aimed toward the improvement of metabolic stability in this series. The best modifications discovered, i.e., replacement of the lactone ring by a nitrile group, replacement of the tetrahydropyran ring by a 6,8-dioxabicydo[3.2.1]octanyl moiety, and replacement of the pendant phenyl ring by a 3-furyl ring, were incorporated in a single molecule to produce inhibitor 9ac (L-708,780). Compound 9ac inhibits the oxidation of arachidonic acid to 5-hydroperoxy-eicosatetraenoic acid by 5-LO (IC50 = 190 nM) and the formation of leukotriene B-4 in human polymorphonuclear leukocytes (IC50 = 3 nM) as well as in human whole blood (IC50 = 150 nM). The good inhibitory profile shown by naphthalenenitrile 9ac is accompanied by an improved resistance to oxidative metabolism. In addition, 9ac is orally active in the functional model of antigen-induced bronchoconstriction in allergic squirrel monkeys (95% inhibition at 0.1 mg/kg).
Pelter, Andrew; Ward, Robert S.; Satyanarayana, Panchagnula, Journal of the Chemical Society. Perkin transactions I, 1983, p. 643 - 647
作者:Pelter, Andrew、Ward, Robert S.、Satyanarayana, Panchagnula、Collins, Peter
DOI:——
日期:——
A convergent mercury mediated lignan synthesis
作者:Andrew Pelter、Robert S. Ward、Panchagnula Satyanarayana、Peter Collins