- Catalytic Asymmetric Synthesis of Quaternary Barbituric Acids
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The catalytic asymmetric α-functionalization of prochiral barbituric acids, a subtype of pseudosymmetric 1,3-diamides, to yield the corresponding 5,5-disubstituted (quaternary) derivatives remains essentially unsolved. In this study 2-alkylthio-4,6-dioxopirimidines are designed as key 1,3-diamide surrogates that perform exceedingly in amine-squaramide catalyzed C-C bond forming reactions with vinyl ketones or Morita-Baylis-Hillmann-type allyl bromides as electrophiles. Mild acid hydrolysis of adducts affords barbituric acid derivatives with an in-ring quaternary carbon in unprecedented enantioselectivity, offering valuable materials for biological evaluations.
- Del Pozo, Sandra,Vera, Silvia,Oiarbide, Mikel,Palomo, Claudio
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supporting information
p. 15308 - 15311
(2017/11/06)
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- Synthesis and antitumor evaluation of 5-(benzo[: D] [1,3]dioxol-5-ylmethyl)-4-(tert -butyl)- N -arylthiazol-2-amines
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A series of novel N-aryl-5-(benzo[d][1,3]dioxol-5-ylmethyl)-4-(tert-butyl)thiazol-2-amines (C1-C31) were synthesized and evaluated for their antitumor activities against HeLa, A549 and MCF-7 cell lines. Some tested compounds showed potent growth inhibition properties with IC50 values generally below 5 μM against the three human cancer cells lines. Compound C27 showed potent activities against HeLa and A549 cell lines with IC50 values of 2.07 ± 0.88 μM and 3.52 ± 0.49 μM, respectively. Compound C7 (IC50 = 2.06 ± 0.09 μM) was the most active compound against A549 cell line, while compound C16 (IC50 = 2.55 ± 0.34 μM) showed the best inhibitory activity against the MCF-7 cell line. The preliminary mechanism of the inhibitory effect was investigated via further experiments, such as morphological analysis by dual AO/EB staining and Hoechst 33342 staining, and cell apoptosis and cycle assessment by FACS analysis. The results illustrated that compound C27 could induce apoptosis and cause both S-phase and G2/M-phase arrests in HeLa cell line. Therefore, compound C27 could be developed as a potential antitumor agent.
- Wu,Fang,Tang,Xiao,Ye,Li,Hu
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p. 1768 - 1774
(2016/09/28)
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- Multi-dimensional target profiling of N,4-diaryl-1,3-thiazole-2-amines as potent inhibitors of eicosanoid metabolism
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Eicosanoids like leukotrienes and prostaglandins play a considerable role in inflammation. Produced within the arachidonic acid (AA) cascade, these lipid mediators are involved in the pathogenesis of pain as well as acute and chronic inflammatory diseases like rheumatoid arthritis and asthma. With regard to the lipid cross-talk within the AA pathway, a promising approach for an effective anti-inflammatory therapy is the development of inhibitors targeting more than one enzyme of this cascade. Within this study, thirty N-4-diaryl-1,3-thiazole-2- amine based compounds with different substitution patterns were synthesized and tested in various cell-based assays to investigate their activity and selectivity profile concerning five key enzymes involved in eicosanoid metabolism (5-, 12-, 15-lipoxygenase (LO), cyclooxygenase-1 and -2 (COX-1/-2)). With compound 7, 2-(4-phenyl)thiazol-2-ylamino)phenol (ST-1355), a multi-target ligand targeting all tested enzymes is presented, whereas compound 9, 2-(4-(4-chlorophenyl)thiazol-2-ylamino)phenol (ST-1705), represents a potent and selective 5-LO and COX-2 inhibitor with an IC50 value of 0.9 ± 0.2 μM (5-LO) and a residual activity of 9.1 ± 1.1% at 10 μM (COX-2 product formation). The promising characteristics and the additional non-cytotoxic profile of both compounds reveal new lead structures for the treatment of eicosanoid-mediated diseases.
- R?dl, Carmen B.,Vogt, Dominik,Kretschmer, Simon B.M.,Ihlefeld, Katja,Barzen, Sebastian,Brüggerhoff, Astrid,Achenbach, Janosch,Proschak, Ewgenij,Steinhilber, Dieter,Stark, Holger,Hofmann, Bettina
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p. 302 - 311
(2014/08/05)
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- Design, synthesis and evaluation of 2-aminothiazole derivatives as sphingosine kinase inhibitors
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Sphingosine kinases (SphK1, SphK2) are main regulators of sphingosine-1-phosphate (S1P), which is a pleiotropic lipid mediator involved in numerous physiological and pathophysiological functions. SphKs are targets for novel anti-cancer and anti-inflammatory agents that can promote cell apoptosis and modulate autoimmune diseases. Herein, we describe the design, synthesis and evaluation of an aminothiazole class of SphK inhibitors. Potent inhibitors have been discovered through a series of modifications using the known SKI-II scaffold to define structure-activity relationships. We identified N-(4-methylthiazol-2-yl)-(2,4′-bithiazol)-2′-amine (24, ST-1803; IC50values: 7.3 μM (SphK1), 6.5 μM (SphK2)) as a promising candidate for further in vivo investigations and structural development.
- Vogt, Dominik,Weber, Julia,Ihlefeld, Katja,Brüggerhoff, Astrid,Proschak, Ewgenij,Stark, Holger
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p. 5354 - 5367
(2014/12/11)
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- Continuous-flow processing of gaseous ammonia using a Teflon AF-2400 tube-in-tube reactor: Synthesis of thioureas and in-line titrations
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A simple tube-in-tube reactor based on the gas-permeable membrane Teflon AF-2400 was used in the continuous flow reaction of gaseous ammonia with isothiocyanates and one isocyanate. A colourimetric in-line titration technique is also reported as a simple method to quantify the amount of ammonia taken up by the solvent in the system. Georg Thieme Verlag Stuttgart · New York.
- Browne, Duncanl.,O'Brien, Matthew,Koos, Peter,Cranwell, Philippa B.,Polyzos, Anastasios,Ley, Steven V.
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scheme or table
p. 1402 - 1406
(2012/07/27)
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