L-methionine methyl ester

Scheme T. Synthesis of Olefin Isosteres of CaaX Analogues, a) (CH3)2C= CHMgBr b) NaBH4 c) Ac20 d) O3, (CH3)2S e) Ph3P=CHC02 CH3 fl LiOH g) EDC, HOBt, L-methionine methyl ester h) CH3S02Cl /) R2MgCuCNCI-BF3 j) HCI L-N-Boc-S-tritylcysteine aldehyde, NaCNBH3 k) TFA, (QHshSiH I) NaOH.

Protease mutants were prepared, which showed higher catalytic activity for the enzymatic polymerization of amino acid esters in an aqueous DMF solution. The molecular weight greatly increased by using a subtilisin mutant (subtilisin 8350) derived from BPN (subtilisin from Bacillus amyloliquefa-ciens) via six site-specific mutants (Met 50 Phe, Gly 169 Ala, Asn 76 Asp, Gin 206 Cys, Tyr 217 Lys, and Asp 218 Ser) in the polymerization of L-methionine methyl ester in the aqueous DMF.240 Another mutant (subtilisin 8397), which is the same as 8350 without... 

The reaction was applied to model dipeptides exemplified by the y-phenyl-hydrazide of N-carbobenzoxy-a-L-glutamyl-L-methionine methyl ester (4) and found to afford the carboxylic acid (S) in good yield without disturbance of the carbo-benzoxy and ester protective groups. The results suggest use of the phenylhydrazide group for protection of carboxyl groups in peptide chemistry. 

L-Methionine methyl ester hydrochloride u-Methionine, methyl ester, hydrochloride (2491-18-1), 76, 123... 

A. N-(Benzyloxycarbonyl)-L-wethionine methyl ester 2). A 3-L, three-necked, Morton flask equipped with an efficient mechanical stirrer, thermometer, and a dropping funnel is charged with L-methionine methyl ester hydrochloride (117.6 g,... 

A. Methyl (S)-2-phthalimido-4-methylthiobutanoate. Into a 2-L, round-bottomed flask fitted with a Dean-Stark apparatus, reflux condenser, and drying tube containing calcium chloride are placed L-methionine methyl ester hydrochloride (50.0 g, 0.25 mol, Notes 1 and 2), phthalic anhydride (37.1 g, 0.25 mol), triethylamine (100 mL, 0.72 mol), and toluene (1 L). The mixture is magnetically stirred and heated under reflux for 4.5 hr at which point approximately 4.5 mL of water has separated. The reaction mixture is allowed to cool to room temperature and the precipitated triethylamine hydrochloride (34 g) is collected by suction filtration. The filtrate is washed with four 300-mL portions of 1 N aqueous hydrochloric acid followed by three 300-mL portions... 

Commercial L-methionine methyl ester hydrochloride (from Aldrich Chemical Company, Inc.) is used or can be easily prepared using a literature procedure.2... 

Methyl (S)-2-phthalimido-4-methylthiobutanoate 2H-lsoindole-2-acetic acid, 1,3-dihydro-a-[2-(methylthio)ethyll-1,3-dioxo-, methyl ester, (S)- (9) (39739-05-4) L-Methionine methyl ester hydrochloride Methionine, methyl ester, hydrochloride, L-(8) L-Methionine, methyl ester, hydrochloride (9) (2491-18-1)... 

A. N-(Benzyloxycarbonyl)-L-methionine methyl ester (2). A 3-L, three-necked, Morton flask equipped with an efficient mechanical stirrer, thermometer, and a dropping funnel is charged with L-methionine methyl ester hydrochloride (117.6 g, 0,66 mol) (Note 1), potassium bicarbonate (282.3 g, 2.82 mol, 500 mol %), water (750 WL), and ether (750 mL), and the solution is cooled to 0°C. Benzyl chloroformate (105... 

N-(Benzyloxycarbonyl)-L-vinylglycine methyl ester 3-Butenoic acid, 2-[[(phenylmethoxy)carbonyl]amino]-, methyl ester, (S)- (10) (75266-40-9) N-(Benzyloxycarbonyl)-L-methionine methyl ester L-Methionine, N-[(phenylmethoxy)carbonyl]-, methyl ester (9) (56762-93-7)... 

Papain catalyzed the polymerization of L-methionine methyl ester hydrochloride to give water-insoluble oligomer with DP = 8-10 (59-61). The resulting water-insoluble oligomer was converted to water-soluble sulfoxide and sulfone derivatives by treatment of DMSO or hydrogen peroxide. Esters of phenylalanine. 

S-Methylcysteine methyl ester, L Methionine methyl ester, L... 

Figure 21.7. Aerobic photo-oxygenation of L-methionine methyl ester in H2O by the...

C16H29N3O3, N-Pivaloyl-D-alanyl-L-proline-N-isopropylamide, 45B, 524 Cl6H30N2O5S2f t-Butoxycarbonyl-D-methionyl-L-methionine methyl ester, 44B, 442... 

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