1655-07-8Relevant articles and documents
Facile carbethoxylation and carbamoylation of ketones
Pazdera, Pavel,Simbera, Jan
, p. 297 - 301 (2011)
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Stork et al.
, p. 2029 (1954)
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Phosphate tricyclic coumarin analogs as steroid sulfatase inhibitors: Synthesis and biological activity
Kozak, Witold,Dasko, Mateusz,Maslyk, Maciej,Pieczykolan, Jerzy S.,Gielniewski, Bartlomiej,Rachon, Janusz,Demkowicz, Sebastian
, p. 44350 - 44358 (2014)
In the present work, we report convenient methods for the synthesis and biological evaluation of phosphate tricyclic coumarin derivatives as potential steroid sulfatase inhibitors. The described synthesis includes the straightforward preparation of 7-hydroxy-2,3-dihydro-1H-cyclopenta[c]chromen-4-one, 3-hydroxy-7,8,9,10-tetrahydro-6H-benzo[c]chromen-6-one and 3-hydroxy-8,9,10,11-tetrahydro-7H-cyclohepta[c]chromen-6-one modified with various phosphate moieties. The inhibitory effects of the synthesized compounds were tested on STS isolated from human placenta as well as the MCF-7, MDA-MB-231 and MDA-MB-435S cancer cell lines. Most of the new STS inhibitors possessed IC50 values between 21 to 159 μM. In the course of our investigation, the largest inhibitory effects in the STS enzyme assays were observed for the three compounds 9p, 9r and 9s, with IC50 values of 36.4, 37.8 and 21.5 μM, respectively (IC50 value of 1.0 μM for the 665-COUMATE used as a reference). The compound 9r, exhibited the highest potency against MCF-7, an estrogen receptor positive (ER+) cell line, with a GI50 value of 24.7 μM. The structure-activity relationships of the synthesized coumarin derivatives with the STS enzyme are discussed.
Enantioselective α-Amination of Acyclic 1,3-Dicarbonyls Catalyzed by N-Heterocyclic Carbene
Santra, Surojit,Maji, Ujjwal,Guin, Joyram
supporting information, p. 468 - 473 (2020/02/04)
Herein, we describe a method for the catalytic enantioselective α-amination of α-substituted acyclic 1,3-ketoamides and 1,3-amidoesters that affords the products possessing N-substituted quaternary stereocenters with a chiral N-heterocyclic carbene (NHC). The reaction is based on the utilization of an intrinsic Br?nsted base characteristic of NHC that enables the catalytic formation of a chiral ion pair comprising the enolate and the azolium ion. A series of challenging open-chain α-substituted 1,3-dicarbonyls are aminated via this method with ee's of ≤99%.
Cobalt-Catalyzed Cross-Couplings between Alkenyl Acetates and Aryl or Alkenyl Zinc Pivalates
Li, Jie,Knochel, Paul
supporting information, p. 11436 - 11440 (2018/08/11)
CoBr2 (5 mol %) in the presence of 2,2′-bipyridyl (5 mol %) enables electrophilic alkenylations between easily accessible alkenyl acetates or tosylates and various functionalized aryl zinc pivalates at ambient temperature. This cobalt-catalyzed
Regioselective catalytic asymmetric C-alkylation of isoxazolinones by a base-free palladacycle-catalyzed direct 1,4-addition
Hellmuth, Tina,Frey, Wolfgang,Peters, Ren
supporting information, p. 2788 - 2791 (2015/03/04)
Isoxazolinones constitute a class of heterocycles utilized for the development of novel drug candidates. The cyclic oxime ester motif is also synthetically useful as it contains functional handles which have previously been used to provide access to an assortment of valuable compound classes not easily accessible by alternative approaches. However, asymmetric methods towards isoxazolinones are notoriously scarce. Herein we report the first catalytic asymmetric alkylations of isoxazolinones forming all-C-substituted quaternary stereocenters. The present studies were driven by the question of how to control the regioselectivity in the competition of different nucleophilic positions. The investigation of a direct 1,4-addition uncovered that a sterically demanding palladacycle catalyst directs the reactivity in the absence of a base nearly exclusively to the nucleophilic C atom, while at the same time it allows for high enantioselectivity and TONs up to 1900.
