- Chiral-Organotin-Catalyzed Kinetic Resolution of Vicinal Amino Alcohols
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A highly efficient kinetic resolution of racemic amino alcohols has been achieved for the first time with a chiral tin catalyst. A chiral organotin compound with 3,4,5-trifluorophenyl groups at the 3,3′-positions of the binaphthyl framework enabled this transformation with excellent yield and high enantioselectivity. The process tolerates aryl- and alkyl-substituted amino alcohols and a variety of other substrates, affording the corresponding products in high enantioselectivity and with s factors up to >500.
- Yang, Hui,Zheng, Wen-Hua
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supporting information
p. 16177 - 16180
(2019/11/03)
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- Easy kinetic resolution of some β-amino alcohols by Candida antarctica lipase B catalyzed hydrolysis in organic media
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Herein, we present an easy and eco-friendly pathway to obtain some enantiomerically enriched β-amino alcohols using essentially as β-blockers. The enzymatic hydrolysis is conducted in hydrophobic organic media, assisted by sodium carbonate and CAL-B. We describe a new and effective procedure in terms of the chemo- and enantioselectivity, which allows for the formation of both enantiomers: the 2-acetamido-1-arylacetates and 2-acetamido-1-arylethanols were obtained with high ee values (up to >99%), while the selectivities reached E >200. The obtained results show a high CAL-B affinity toward the deacylation of the 2-acetamido-1-arylacetates compared to the acylation one. The structure of the 2-acetamido-1-arylacetates had a significant influence on both reactivity and selectivity of the CAL-B catalyzed deacylation. A multigram scale O-deacylation of racemic 2-acetamido-1-phenylacetate has been carried out, giving access both enantiomers with high enantiomeric purity and good isolated chemical yields.
- Alalla, Affef,Merabet-Khelassi, Mounia,Riant, Olivier,Aribi-Zouioueche, Louisa
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p. 1253 - 1259
(2016/11/23)
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- IMIDAZOL[1,2-alpha]QUINOXALINES AND DERIVATIVES FOR THE TREATMENT OF CANCERS
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Imidazo[1,2-a]quinoxaline compounds for the treatment of cancers as well as pharmaceutical compositions that include these compounds and their uses in therapy. The compound of general formula (I):
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Page/Page column 1
(2010/10/19)
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- 1,2-oxazines as building blocks for stereoselective synthesis: Preparation of oxygen-substituted 1,2-oxazines, either by alcohol addition or by epoxidation, and subsequent hydrogenation leading to 1,2-amino alcohols and pyrrolidines
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Stereodefined oxygen-substituted 1, 2-oxazines were prepared by three different routes. The cycloaddition of enol ethers such as 1 with a-nitrosoalkenes generated in situ gave the heterocycles 3 and 4. Acid-catalysed additions of alcohols to the 6H-1, 2-oxazines 5 led to mixtures of the adducts 6 and the substitution products 7 with moderate chemoselectivity. Epoxidation of the 6H-1, 2-oxazines 5 proceeded more efficiently and furnished the corresponding epoxides 25 and 32 in reasonable to excellent yields. It was demonstrated that the resulting oxygen-substituted 1, 2-oxazines were suitable precursors for the preparation of cyclic or acyclic primary and secondary amines in racemic or enantiopure form. Hydrogenation of the 3-phenyl-substituted 1, 2-oxazines 3 and 25a and of (6S)- and (6R)-32 preferentially furnished the 1, 2amino alcohols 15, rac-29 and (2S)- and (2R)-29. On the other hand, reduction of the 3-ethoxycarbonyl-substituted 1, 2-oxazines 4, 6d and 20 led to the formation of the N-protected proline esters 21-24 in moderate yields. It was also found that the 5-methyl-6H-1, 2-oxazine 10 was a good precursor for the propargylic ether 11, which allowed a Pauson-Khand reaction leading to the tricyclic compounds 13 and 14. Hydrogen peroxide converted 10 into a hydroperoxide intermediate, which was further transformed into the l, 2-oxazin-6-one 28b. Overall, the results demonstrate the remarkable potential of suitably substituted 1, 2-oxazine derivatives for the stereoselective synthesis of amines.
- Zimmer, Reinhold,Buchholz, Monika,Collas, Markus,Angermann, Joerg,Homann, Kai,Reissig, Hans-Ulrich
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experimental part
p. 4111 - 4121
(2010/10/02)
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- INHIBITORS OF Akt ACTIVITY
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Invented are novel thiophene compounds, the use of such compounds as inhibitors of protein kinase B activity and in the treatment of cancer and arthritis.
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Page/Page column 62
(2010/11/27)
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- INHIBITORS OF AKT ACTIVITY
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Invented are novel 1 H-imidazo[4,5-c]pyridin-2-yl compounds, the use of such compounds as inhibitors of protein kinase B activity and in the treatment of cancer and arthritis.
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Page/Page column 126
(2008/06/13)
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- Design and synthesis of novel imidazo[1,2-a]quinoxalines as PDE4 inhibitors
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New imidazo[1,2-a]quinoxaline derivatives have been synthesised by condensation of an appropriate α-aminoalcohol with a quinoxaline followed by intramolecular cyclisation and nucleophilic substitutions. Their phosphodiesterase inhibitory activities have b
- Deleuze-Masquefa, Carine,Gerebtzoff, Gregori,Subra, Guy,Fabreguettes, Jean-Roch,Ovens, Annabel,Carraz, Maelle,Strub, Marie-Paule,Bompart, Jacques,George, Pascal,Bonnet, Pierre-Antoine
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p. 1129 - 1139
(2007/10/03)
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- 2,3-DISUBSTITUTED ISOXAZOLIDINES, A AGENTS CONTAINING THEM AND THEIR USE
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The invention relates to compounds of the formula I: in which A denotes an optionally substituted radical from the series comprising alkyl, acyl, cycloalkyl, aryl and heteroaryl; A1 represents CO, CS, C=NH, CN-alkyl, CN-O-alkyl, SO, optionally substituted
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