Synthesis of aspartame via asymmetric hydrogenation of N-protected (Z)-N-.alpha.-L-aspartyl-.DELTA.-phenylalanine methyl ester

1986 ◽  
Vol 51 (7) ◽  
pp. 1126-1128 ◽  
Author(s):  
Claudio Fuganti ◽  
Piero Grasselli ◽  
Luciana Malpezzi ◽  
Paolo Casati
Keyword(s):  
Methyl Ester ◽  
Asymmetric Hydrogenation ◽  
Phenylalanine Methyl Ester

Effects of the preparation method on the performance of the Cu/ZnO/Al2O3 catalyst for the manufacture of l-phenylalaninol with high ee selectivity from l-phenylalanine methyl ester

2014 ◽  
Vol 4 (4) ◽  
pp. 1132-1143 ◽  
Author(s):  
Zhangping Shi ◽  
Xiuzhen Xiao ◽  
Dongsen Mao ◽  
Guanzhong Lu
Keyword(s):  
Methyl Ester ◽  
Catalytic Hydrogenation ◽  
Preparation Method ◽  
Phenylalanine Methyl Ester ◽  
Al2o3 Catalyst

Efficient catalytic hydrogenation of l-phenylalanine methyl ester to l-phenylalaninol over the Cu/ZnO/Al2O3 catalyst with ~100% ee selectivity.

scholarly journals 4-fluorobenzylamine and phenylalanine methyl ester conjugates OF 2-nitroimidazole: Evaluation as hypoxic cell radiosensitizers

1992 ◽  
Vol 22 (3) ◽  
pp. 593-596 ◽  
Author(s):  
Pradeep K. Arg ◽  
Sudha Garg ◽  
William G. Degraff ◽  
Michael R. Zalutsky ◽  
James B. Mitchell
Keyword(s):  
Methyl Ester ◽  
Hypoxic Cell ◽  
Phenylalanine Methyl Ester

Crystal-to-Crystal Diastereoselective Transformation of 2,4,6-Triisopropyl-4'-(S)-phenylalaninocarbonylbenzophenone Methyl Ester

1998 ◽  
Vol 54 (6) ◽  
pp. 907-911 ◽  
Author(s):  
H. Hosomi ◽  
Y. Ito ◽  
S. Ohba
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Methyl Ester ◽  
Absolute Configuration ◽  
Crystal Structure Analysis ◽  
X Ray Diffraction ◽  
Pass Filter ◽  
X Ray ◽  
Ultra High Pressure ◽  
Phenylalanine Methyl Ester

Dissymmetry of the photoproduct was induced by using a chiral substituent, (S)-methylphenylalanine, in the title compound {N-4-(2,4,6-triisopropylbenzoyl)benzoyl]-(S)-phenylalanine methyl ester (I)}. On irradiation with light from a 250 W ultra-high-pressure Hg lamp for 7 h through a long-pass filter, the photoreaction in a crystal was 100% complete without the loss of crystallinity. The crystal structures (I), before, and (II) {N-[4-(7-hydroxy-3,5-diisopropyl-8,8-dimethylbicyclo[4.2.0]octa-1,3,5-trien-7-yl)benzoyl]-(S)-phenylalanine methyl ester}, after photocyclization, have been determined by X-ray diffraction. For comparison, a crystal structure analysis has also been carried out for the photoproduct (III) of the 3′-COOMe derivative after recrystallization {methyl 3-(7-hydroxy-3,5-diisopropyl-8,8-dimethylbicyclo[4.2.0]octa-1,3,5-trien-7-yl)benzoate}. The dihedral angle between the central carbonyl plane and the triisopropylphenyl ring deviates from 90° by 10 (1)° in (I), which makes an imbalance in the intramolecular O(carbonyl)...H(methine) distances of the isopropyl groups at positions 2 and 6. The crystal structure of (II) indicates that the nearer methine H was predominantly abstracted by the carbonyl O atom in the reaction. The absolute configuration around the asymmetric C atom in the cyclobutenol ring of the product is S.

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