4-oxo-L-proline

Na and a trace of FeCls added under Og-free Ng to liq. NHg, methyltriphenyl-phosphonium bromide added with stirring when the blue color has disappeared, NH3 replaced by ether and tetrahydrofuran, the resulting suspension warmed 5 min. at 50°, a soln. of carbobenzoxy-4-oxo-L-proline in tetrahydrofuran added at room temp, with stirring during 10 min., refluxed several hrs., and the product isolated as the dicyclohexylammonium salt dicyclohexylammonium carbobenzoxy-4-methylene-L-prolinate. Y 84%. M. Bethell and G. W. Kenner, Soc. 1965, 3850. 

Of particular interest is the fact that a number of amino acids present in the actinomycins are not constituents of cellular proteins. These include D-amino acids, e.g., D-valine and D-alloisoleucine N-methylamino acids, e.g., sarcosine, N-methylvahne, N-methylalanine and the imino acid, 4-oxo-L-proline. Although the chemical differences between actinomycins are generally small, there are significant quantitative differences in their biological activity (Table 1). 

Biogenesis of the amino acids, D-valine and D-alloisoleucine, 4-oxo-L-proline and hydroxy-L-proline, sarcosine, N-methyl-L-valine, and N-methylalanine. 

Table 5. Distrihution of label in peptide-hound L-proline, d-hydroxy-L-proline and 4-oxo-L-proline...

Salzman, L. A., H. Weissbach, and E. Katz Conversion of C - and cis- or trans-4-H -L-proline to 4-hydroxy-L-proline and 4-oxo-L-proline by Streptomyces anti-bioticus. Proc. Natl. Acad. Sci. U.S. 54, 542 (1965). 

Derivatives of the 2,5-diazabicyclo[2.2.1]heptaine ring system (bridged piperazines) have been prepared from 4-hydroxyprolines. In a multistep transformation from tra j-4-hydroxy-L-proline (the last step was cyclization with benzylamine) a mixture of diastereoisomers 71 was obtained and separated [92H(34)241]. In a similar manner, the methyl and oxo analogs were obtained [67AJC1493 92H(34)679]. The commercially available N-... 

The enzyme 5-oxo-L-prolinase, which catalyses the conversion of 5-oxo-L-proline to L-glutamate coupled to the consumption of adenosine triphosphate (ATP) (Figure 36.39), was shown by Williamson and Meister to act also on a synthetic substrate, L-2-oxothiazolidine -carboxylate, which is an analog of 5-oxoproline with the 4-methylene group replaced by sulfur. 

CAS 28874-51-3 (L) 54571-67-4 (DL) EINECS/ELINCS 249-277-1 (L) 259-234-9 (DL) Synonyms 5-Oxo-DL-proline, sodium salt 5-Oxo-L-proline, sodium salt PCA-Na PCA Soda Sodium 5-oxo-L-prolinate Sodium pyroglutamate Sodium DL-2-pyrrolidone-5-carboxylate Sodium L-2-pyrrol idone-5-carboxyl ate Definition Sodium salt of pyroglutamic acid... 

Amino-4,6-dimethyl-3-oxo-3//-phenoxazine-l,9-dicarboxylic acid also named actinocin is the chromophor of the red antineoplastic chromopeptide aetinomyein D (formula A). Two cyclopenta-peptide lactone rings (amino acids L-threonine, D-valine, L-proline, sarcosine, and 7V-methyl-L-valine) are attached to the carboxy carbons of actinocin by two amide bonds involving the amino groups of threonine. 

Some workers avoid delay. Pai)adium-on-carbon was used effectively for the reductive amination of ethyl 2-oxo-4-phenyl butanoate with L-alanyl-L-proline in a synthesis of the antihyperlensive, enalapril maleate. SchifTs base formation and reduction were carried out in a single step as Schiff bases of a-amino acids and esters are known to be susceptible to racemization. To a solution of 4,54 g ethyl 2-oxO 4-phenylbutanoate and 1.86 g L-alanyl-L-proline was added 16 g 4A molecular sieve and 1.0 g 10% Pd-on-C The mixture was hydrogenated for 15 hr at room temperature and 40 psig H2. Excess a-keto ester was required as reduction to the a-hydroxy ester was a serious side reaction. The yield was 77% with a diastereomeric ratio of 62 38 (SSS RSS)((55). 

The hexahydro-l//-pyrrolo[2,l-f][l,4]oxazin-l-one 82 (obtained by radical cyclization see Section 11.11.7.3) was transformed into the proline derivative 83 by hydrogenation in the presence of the Pearlman s catalyst and a stoichiometric amount of trifluoroacetic acid (TFA) (Scheme 10). This reaction led with high yield to the disub-stituted proline 83 in an enantiomerically pure form <2003SL1058>. In an analogous approach, the chiral (4/ ,7/ ,8aA)-methyl 6,6-dimethyl-l-oxo-4-phenylhexahydro-l//-pyrrolo[2,l-r-][l,4]oxazine-7-carboxylate 84 was hydrogenated on Pd(OH)2 in the presence of TFA to give enantiomerically pure 5,5-dimethylproline derivatives 85 <2001SL1836> (Scheme 10). 

C ol I zOsi 68767-26-0) see Loxoprofen (.S)-iV-U-ctlioxycarhonyl-3-oxo-3-phenylpropyl)-l.-alanine (C,5ll 9N05 87269-99-6) see. Ramipril 1-l/V-l l-(cthoxycarbonyl)-3-oxo-3-phenylpropyl]-L-ala-nyl]-l.-proline phcnylmcthyl ester (C27H,2N2Ofi 105878-11-3) see Enalapril 17[Pg.2373]

Almquist, R. G., Chao, W. R., Jennings-White, C. Synthesis and biological activity of carboxylic acid replacement analogues of the potent angiotensin converting enzyme inhibitor 5(S)-benza-mido-4-oxo-6-phenylhexanoyl-L-proline. J. Med. Chem. 1985, 28, 1067-1071. 

Chlor-propyl)-2,4-dioxo-5-methyl-imidazolidin bildet durch intramolekulare N-Al-kylierung (vgl. S. 521) 2,4-Dioxo-5-methyl-l,3-diaza-bicyclo[3.3.0]octan, das sich zu 2-Methyl-DL-prolin hydrolysieren laBt. Die benotigte Vorstufe erhalt man durch Bucherer-Reaktion (s.S. 538) mit l-Hydroxy-4-oxo-pentan5 ... 

Lisinoprii has been prepared by the scheme outlined in Figure 1 (7,8). The dipeptide, Ng-trifluoroacetyl-L-lysyl-L-proline (D is subjected to reductive alkyiation with ethyl 2-oxo-4-phenylbutanoate over Raney Nickel via a Schiff base to yield a diastereomeric mixture 4 (SSS and RSS). Hydrolysis of the N -trifluoroacetyl moiety and saponification of the ethyl ester followed by crystallization in ethanol/water and final recrystallization in water yield lisinopril (SSS, 5) of greater than 98% purity in about 65% yield (based on In addition to this synthetic route, others have also been described in the literature (9-12). 

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