32435-70-4

Upstream product

• 5469-44-3 2-methyl-4-benzyl-4H-oxazolin-5-one 
• 2577-90-4 methyl (2S)-2-amino-3-phenylpropanoate 
• 7524-50-7 methyl (2S)-2-amino-3-phenylpropanoate hydrochloride 
• 109927-10-8 racemic Ac-Phe-ΔPhe-OMe 
• 82690-96-8 N-Acetyldehydrophenylalanylphenylalanine methyl ester 
• 38879-46-8 (Z)-4-benzylidene-2-methyl-5(4H)-oxazolone 
• 78087-68-0 N-(α-acetylamino-cinnamoyl)-L-phenylalanine 
• 57986-20-6 N-acetyl dehydrophenylalanyl-(S)-phenylalanine methyl ester 
• 13649-97-3 (S)-4-benzyl-2-methyl-4H-oxazol-5-one 
• 15028-44-1 DL-phenylalanine methyl ester 
• 186581-53-3 diazomethane 
• 24809-18-5 Ac-D-Phe-L-Phe-OH 

Relevant academic research and scientific papers

Electrostatic interaction and induced fitting of the rhodium(I) complex coordinated by diphosphine ligand having an amino group in the diastereoselective hydrogenation of dehydrodipeptides

Rhodium(I)-[2-[2-(dimethylamino)ethyl]-1,3-propanediyl]bis(diphenylphosphine) (DPP-AE) catalyst achieved an effective 1,4-asymmetric induction and afforded high diastereoselectivity (max. 96% d.e.) in the hydrogenation of dehydrodipeptides in protic solve

ASYMMETRIC SYNTHESIS OF AMINO ACIDS VIA THE CATALYTIC REDUCTION OF ACYLAMINOACRYLIC ACID AZLACTONE DERIVATIVES. 24. REDUCTIVE AMINOLYSIS OF 2-METHYL-4-BENZYLIDENE-Δ2-OXAZOLIN-5-ONE UPON TREATMENT WITH A CATALYTIC SYSTEM BASED ON S-PHENYLALANINE DERIVATIVES

Reductive aminolysis of 2-methyl-4-benzylidene-Δ2-oxazolin-5-one upon treatment with a PdCl2-S-phenylalanine ester (dimethylamide) catalytic system leads to the formation of the corresponding acylated dipeptide derivatives, with the R,S-configuration (diastereomer) predominating (DE 9-27percent).The reaction stereoselectivity in dimethoxyethane increases sharply in the presence of triethylamine additive, and in the case of S-phenylalanine methyl ester reaches 47percent.The stepwise mechanism for this process has been studied.

ASYMMETRIC SYNTHESIS OF AMINO ACIDS VIA THE CATALYTIC REDUCTION OF SUBSTITUTED ACYLAMINOACRYLIC ACID AZLACTONES. 26. AMINOLYSIS OF 2-METHYL-4-BENZYLOXAZOLIN-5-ONE UPON REACTION WITH S-PHENYLALANINE DERIVATIVES

The kinetics of aminolysis and racemization of 2-methyl-4-benzyloxazolin-5-one upon reaction with S-phenylalanine methyl ester have been studied in dimethoxyethane solvent.The rates of aminolysis and racemization are comparable.Addition of an achiral component, namely Et3N, to the reaction mixture, however, dramatically increases the rate of racemization.The presence of Et3N also increases the ratio of rate constants for the formation of RS- and SS-diastereomers, which determines the reaction stereoselectivity.

Efficient 1,4-Asymetric Induction Utilizing Electrostatic Interaction between Ligand and Substrate in the Asymmetric Hydrogenation of Didehydrodipeptides

Electrostatic interaction between the amino group of the achiral 3-dimethylaminopropylidenebismethylenebis(diphenylphosphine) (1) and the carboxy group of the substrate enable an effective 1,4-asymmetric induction in the RhI-catalysed hydrogenation of didehydrodipeptides, to give (S,S)-or (R,R)-products selectively.The selectivity reached up to 94percent diastereoisomeric excess with acetyl didehydrodipeptides and 92percent with benzyloxycarbonyl substrates.

ASYMMETRIC HOMOGENOUS REDUCTION OF DEHYDROPEPTIDES

Monodehydropeptides with the dehydroaminoacid fragment in C-terminal or N-terminal position were synthetized as well as a family with the general formula Ac-ΔPhe-(Gly)n-Leu-OR (n = 0-2, R = H or Me).Asymmetric reduction of these compounds catalyzed by chiral rhodium complexes was investigated.The results were discussed in terms of double asymmetric induction.A method was developped to avoid the use of both enantiomers of the substrate or of the catalyst, it consists in the total reduction of a racemic dehydropeptide.The products distribution gives access to the two desired facial selectivities.

ASYMMETRIC HYDROGENATION WITH RHODIUM(I)-CHIRAL DIPHOSPHINITES. THE EFFECT OF THE DIMETHYLAMINO GROUP OF THE LIGAND ON THE ASYMMETRIC INDUCTION.

New chiral diphosphinites were prepared starting from ( plus )-diethyl tartrate. The asymmetric hydrogenation of dehydroamino acids, itaconic acid and dehydrodipeptides was studied using Rh(I)-diphosphinite catalysts. In the hydrogenation of dehydroamino acid derivatives, an introduction of omega -(dimethylamino)alkyl group in the ligands did not raise the optical yield. By the use of Rh(I)-diphosphinite having 3-(dimethylamino)propyl group the inversion of the preferred product was observed. 19 refs.

ASYMMETRIC HYDROGENATION OF DEHYDRODIPEPTIDES WITH RHODIUM(I)-CHIRAL DIPHOSPHINITES. SELECTIVE (S,S)- AND (R,R)-PRODUCT FORMATION BY DOUBLE ASYMMETRIC INDUCTION.

In the hydrogenation of dehydrodipeptides, the effect of chiral center of the substrate ((S) or (R)) on the asymmetric induction was examined using the catalysts of Rh(I)-chiral diphosphinite containing pyrrolidine moiety (POP). The catalysts with POP's h

Synthesis of Chiral Dipeptides by means of Asymmetric Hydrogenation of Dehydro Dipeptides

Asymmetric hydrogenation of various dehydro dipeptides was carried out by using rhodium complex catalysts with a variety of chiral diphosphine ligands.The efficiency of chiral diphosphine ligands as well as the effect of the chiral center in the substrate

Stereoselective Synthesis of Dipeptides by Asymmetric Reduction of Dehydropeptides Catalyzed by Chiral Rhodium Complexes

Asymmetric catalysis was used to control the creation of an asymmetric center in a chiral dehydropeptide.The reduction of Ac-ΔPhe-(S)-Phe-OR (R=H or Me) was studied as a model.Depending on the type of chiral rhodium catalyst used, it was possible to selec