24461-61-8Relevant articles and documents
Enantioselective ammonolysis of phenylglycine methyl ester with lipase-pluronic nanoconjugate in tertiary butanol
Wu, Xiaoling,Wang, Rui,Zhang, Yifei,Ge, Jun,Liu, Zheng
, p. 1407 - 1410 (2014)
Asymmetrical ammonolysis of (R)- and (S)-phenylglycine methyl ester was carried out by using a lipase (CALB)-polymer (Pluronic) nanoconjugate as the catalyst, displaying a 11-fold increased catalytic rate compared to the free CALB in tertiary butanol. Graphical Abstract: The asymmetrical ammonolysis of (R)- and (S)-phenylglycine methyl ester was accomplished using a lipase-Pluronic nanoconjugate, displaying a 11-fold higher catalytic rate compared to the free lipase.[Figure not available: see fulltext.]
Dynamic kinetic resolution of phenylglycine esters via lipase-catalysed ammonolysis
Wegman,Hacking,Rops,Pereira,Van Rantwijk,Sheldon
, p. 1739 - 1750 (1999)
Ammonolysis of D,L-phenylglycine methyl ester catalysed by Novozym 435 at 40°C in tert-butyl alcohol gave D-phenylglycine amide in 78% ee at 46% conversion, corresponding to an enantiomeric ratio (E) of 16. Lowering the temperature improved the enantioselectivity (E = 52 at -20°C). Combination of ammonolysis with pyridoxal-catalysed in situ racemisation of the unconverted ester (dynamic kinetic resolution), at -20°C, gave D- phenylglycine amide with 88% ee at 85% conversion. The amide racemised much slower than the ester at this low temperature.
Rubrosides A-H, new bioactive tetramic acid glycosides from the marine sponge Siliquariaspongia japonica
Sata,Wada,Matsunaga,Watabe,Van Soest,Fusetani
, p. 2331 - 2339 (1999)
Eight new tetramic acid glycosides named rubrosides A-H have been isolated from the marine sponge Siliquariaspongia japonica. Their structures were elucidated on the basis of spectral data as tetramic acid glycosides containing polyenes terminating in a 4-chloro-2-methyltetrahydrofuran ring. The absolute stereochemistry of the furan functionality in the two major metabolites, rubrosides D and F, was determined by the NMR method using chiral anisotropic reagents for tetrahydro-2-furoic acid derived by RuO4 oxidation. The absolute stereochemistry of tetramic acid and of the sugar moieties in all rubrosides was deduced by chiral GC analysis of chemical degradation products. The rubrosides induced numerous large intracellular vacuoles in 3Y1 rat fibroblasts at concentrations of 0.5-1.0 μg/mL, and rubrosides A, C, D, and E were cytotoxic against P388 murine leukemia cells with IC50 values of 0.046-0.21 μg/mL. Most rubrosides show antifungal activity against Aspergillus fumigatus and Candida albicans.
A Structure?Activity Relationship Study of Novel Hydroxamic Acid Inhibitors around the S1 Subsite of Human Aminopeptidase N
Lee, Jisook,Drinkwater, Nyssa,McGowan, Sheena,Scammells, Peter
, p. 234 - 249 (2020/10/28)
Aminopeptidase N (APN/CD13) is a zinc-dependent ubiquitous transmembrane ectoenzyme that is widely present in different types of cells. APN is one of the most extensively studied metalloaminopeptidases as an anti-cancer target due to its significant role in the regulation of metastasis and angiogenesis. Previously, we identified a potent and selective APN inhibitor, N-(2-(Hydroxyamino)-2-oxo-1-(3′,4′,5′-trifluoro-[1,1′-biphenyl]-4-yl)ethyl)-4-(methylsulfonamido)benzamide (3). Herein, we report the further modifications performed to explore SAR around the S1 subsite of APN and to improve the physicochemical properties. A series of hydroxamic acid analogues were synthesised, and the pharmacological activities were evaluated in vitro. N-(1-(3′-Fluoro-[1,1′-biphenyl]-4-yl)-2-(hydroxyamino)-2-oxoethyl)-4-(methylsulfonamido)benzamide (6 f) was found to display an extremely potent inhibitory activity in the sub-nanomolar range.
Stereoretentive N-Arylation of Amino Acid Esters with Cyclohexanones Utilizing a Continuous-Flow System
Ichitsuka, Tomohiro,Komatsuzaki, Shingo,Masuda, Koichiro,Koumura, Nagatoshi,Sato, Kazuhiko,Kobayashi, Shū
supporting information, p. 10844 - 10848 (2021/05/31)
The N-arylation of chiral amino acid esters with minimal racemization is a challenging transformation because of the sensitivity of the α-stereocenter. A versatile synthetic method was developed to prepare N-arylated amino acid esters using cyclohexanones as aryl sources under continuous-flow conditions. The designed flow system, which consists of a coil reactor and a packed-bed reactor containing a Pd(OH)2/C catalyst, efficiently afforded the desired N-arylated amino acids without significant racemization, accompanied by only small amounts of easily removable co-products (i. e., H2O and alkanes). The efficiency and robustness of this method allowed for the continuous synthesis of the desired product in very high yield and enantiopurity with high space-time yield (74.1 g L?1 h?1) and turnover frequency (5.9 h?1) for at least 3 days.