ÉTUDES SUR LA SYNTHÈSE DE L’HYDROXYPROLINE À PARTIR DE DÉRIVÉS DE L’ACIDE 2-AMINO-4-PENTÈNOÏQUE

1956 ◽  
Vol 34 (4) ◽  
pp. 502-514 ◽  
Author(s):  
Roger Gaudry ◽  
Louis Berlinguet ◽  
André Langis ◽  
Gérard Paris

A systematic investigation of the synthesis of 4-hydroxy-DL-proline and 2-amino-4-dihydroxyvaleric acid has been made, starting from the following derivatives of 2-amino-4-pentenoic acid: ethyl allylacetamidomalonate, ethyl allylacetamidocyanoacetate, 2-phthalimidopentenoic acid, allylacetamido-malonic acid, acetylallylglycine, 5-allylhydantoin, and 3-phenyl-5-allylhydantoin. Chlorine or bromine was added to the double bond of these compounds, and the reaction products were either derivatives of 5-halogenated-4-valerolactones or derivatives of 4,5-dihalogenated pentanoic acids, depending on whether the carboxyl group of the pentanoic acid was free or not when the halogenation reaction was carried out. Acid hydrolysis followed by treatment with barium hydroxide always gave mixtures, in different ratio, of 4-hydroxy-DL-proline and 2-amino-4,5-dihydroxyvaleric acid which were analyzed and isolated as the copper salts. In the case of 5-(2,3-dibromopropyl)hydantoin and 3-phenyl-5-(2,3-dibromopropyl)hydantoin, no cyclization could be obtained.


1983 ◽  
Vol 48 (1) ◽  
pp. 304-311 ◽  
Author(s):  
Jiří Křepelka ◽  
Jan Beneš ◽  
Vladimír Pouzar ◽  
Jaroslav Vachek ◽  
Jiří Holubek

Condensation of triethyl ester of 1,1,5-pentanetricarboxylic acid (XI) with substituted guanidines XXII - XXIX gave acids II - IX, which were converted into esters XI - XIX. The acid II and the ester XI were obtained as mixtures of positional isomers. Analogously, condensation of the triester XXI with dicyanodiamide gave rise to acid X, whose nitrile group, under conditions of esterification of a carboxyl group, produced iminoether XX. In pharmacological tests for antineoplastic activity the compounds prepared exhibited weaker efficacy than 5-(2-amino-6-hydroxy-4-oxo-3,4-dihydro-5-pyrimidinyl)pentanoic acid (I), employed as standard.





1985 ◽  
Vol 20 (2) ◽  
pp. 36-43 ◽  
Author(s):  
Klaus L.E. Kaiser ◽  
Juan M. Ribo ◽  
Brian M. Zaruk

Abstract This paper gives the results of part of a systematic investigation into contaminant toxicity to Photobacterium phosphoreum in the Microtox™ test. Reported are the toxicity values for 39 para-chloro substituted benzene derivatives of the general formula l-Cl-C6h4-4-X=CH2CH(NH2)COOH, F, SO2NH2, OCH2COOH, CH2COOH, CONHNH2, NHCOCH3, CONH2, CH=CHCOOH, SeOOH, CH2NH2, CH2CH2NH2, NO2, H, CF3, CHO, CH2OH, OH, CH3, CCl3, COCH3, COOH, NH2, SO2C6H5, Cl, CH2COCH3, COCl, CN, OCH3, NCO, NHCH3, I, COC6H5, CH2Cl, SH, CH2SH, NCS, CH2CN and SO2C6H4Cl. Except for the last compound, whose solubility is below the required concentration, the toxicities increase in the presented order with a total range of more than three orders of magnitude. The data are discussed in terms of quantitative structure-toxicity correlations with compound-specific structural parameters. In combination with a previously developed submodel on chlorinated benzenes, phenols, nitrobenzenes and anilines, the observed relationships allow the prediction of the toxicity of some 780 possible chloro derivatives of the general formula C6H5-nClnX, where n=<5 and X is a functional group as listed above.



1981 ◽  
Vol 46 (6) ◽  
pp. 1397-1404 ◽  
Author(s):  
Rudolf Kotva ◽  
Jiří Křepelka ◽  
Antonín Černý ◽  
Vojtěch Pujman ◽  
Miroslav Semonský

On condensation of 6-substituted trialkyl esters of 2-carboxy-1,7-heptanedioic acids XIII-XXIII with guanidineand subsequent saponification 2-substituted 5-(2-amino-6-hydroxy-4-oxo-3,4-dihydro-5-pyrimidinyl)pentanoic acids II-XII were prepared. From the pharmacological point of view some of the substances prepared had a potentiating effect on the antileukemia effect of 5-fluorouracil in mice and the antineoplastic effect manifested by a diminution of the tumours in animals with experimental tumours.



1982 ◽  
Vol 47 (9) ◽  
pp. 2525-2529 ◽  
Author(s):  
Rudolf Kotva ◽  
Jiří Křepelka ◽  
Jaroslav Vachek

Condensation of trialkyl esters of 6-substituted 2-carboxy-1,7-heptanedioic acids XII-XVII with urea or thiourea and subsequent saponification gave 2-substituted 5-(2,6-dihydroxy-4-oxo-3,4-dihydro-5-pyrimidinyl)pentanoic acids II-VI or 5-(2-mercapto-6-hydroxy-4-oxo-3,4-dihydro-6-pyrimidinyl)pentanoic acids VII-XI, respectively. Compounds II, VII and X had a weak antineoplastic effect in animals with experimental transplantable tumours.



ChemInform ◽  
2010 ◽  
Vol 32 (51) ◽  
pp. no-no
Author(s):  
S. S. Koval'skaya ◽  
N. G. Kozlov
Keyword(s):  


Author(s):  
Marie-Rose Van Calsteren ◽  
Ricardo Reyes-Chilpa ◽  
Chistopher K Jankowski ◽  
Fleur Gagnon ◽  
Simón Hernández-Ortega ◽  
...  

The tropical tree Calophyllum brasiliense (Clusiaceae) grows in the rain forests from Brazil to Mexico. Its leaves, as well as those of other Calophyllum species, are rich sources of chromanone acids, such as apetalic acid, isoapetalic acid, and their derivatives. Apetalic acid has shown significant antimycobacterial activity. The biological activity of apetalic acid has been related to the configuration of three asymmetric centers and the stereochemistry of the molecule; however, the C-19 configuration in the acidic side chain has not been fully resolved. For this reason, the unequivocal determination of the absolute configuration by means of X-ray crystallography in a sample of unique homogeneous apetalic acid stereoisomer was the most important point to start this study. We prepared some chiral amides using the carboxyl group. We determined the C-19 stereochemistry of apetalic acid, and its specific chiral derivatives, using NMR, X-ray diffraction methods, and molecular mechanics. Finally, we observed that steric hindrance in the side chain of apetalic acid leads to restriction of rotation around the pivotal link C-10 and C-19 establishing chiral centers at C2(R), C3(S), and C19(R). We were able to separate derivatives of these two high-rotatory-barrier conformers of apetalic acid by forming diastereoisomeric amides with phenylglycine methyl ester having a chiral center at C-2’. Our results allowed the conclusion of the existence of atropisomerism in the apetalic acid molecule.



Synthesis ◽  
2017 ◽  
Vol 49 (11) ◽  
pp. 2443-2460 ◽  
Author(s):  
Kim Nguyen ◽  
Pascal Sutter ◽  
Philip Kraft

Since the nucleophilic opening of isobutylene oxide competes with the formation of polyethers, the 2,2-dimethyl-1,4-dioxabutane moiety constitutes the most important cost driver in the synthesis of linear musks. Therefore, musk motifs devoid of this structural element would be highly attractive. Based on molecular modeling considerations, 5-methyl-substituted (3E)-configured alk-3-enoic esters accessible by deconjugative Knoevenagel reaction with malonic acid in the presence of piperidinium acetate with citronellal and Florhydral as substrates, were synthesized but showed disappointing olfactory properties, as did inverted ester motifs or dimethyl carbinols. Moving closer to carba-Serenolide structures, isobutyronitrile was added to m-isopropenylcumene. DIBAL-H with subsequent alanate reduction provided 4-(3-isopropylphenyl)-2,2-dimethylpentan-1-ol, which was either directly esterified, or esterified after Birch reduction and full hydrogenation. While these target structures were all odorless, (2E)-4-(3,3-dimethylcyclohexyl)pent-2-en-1-yl cyclopropanecarboxylate turned out to be a decent musk odorant (4.1 ng/L air). This proved the concept of an (E)-configured double bond in the middle of anticipated horseshoe-shaped conformers, but casted doubt on the non-importance of the ether oxygens in Helvetolide and Serenolide. Therefore, carba-Helvetolide and carba-Serenolide were synthesized from 3,3-dimethylcyclohexanone, and indeed turned out to be completely odorless. So polar interactions play a crucial role in the receptor interaction of these linear musks beyond merely favoring horseshoe-shaped conformers.



2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Liujuan Zheng ◽  
Haowen Wang ◽  
Aili Fan ◽  
Shu-Ming Li

Abstract Oxepinamides are derivatives of anthranilyl-containing tripeptides and share an oxepin ring and a fused pyrimidinone moiety. To the best of our knowledge, no studies have been reported on the elucidation of an oxepinamide biosynthetic pathway and conversion of a quinazolinone to a pyrimidinone-fused 1H-oxepin framework by a cytochrome P450 enzyme in fungal natural product biosynthesis. Here we report the isolation of oxepinamide F from Aspergillus ustus and identification of its biosynthetic pathway by gene deletion, heterologous expression, feeding experiments, and enzyme assays. The nonribosomal peptide synthase (NRPS) OpaA assembles the quinazolinone core with d-Phe incorporation. The cytochrome P450 enzyme OpaB catalyzes alone the oxepin ring formation. The flavoenzyme OpaC installs subsequently one hydroxyl group at the oxepin ring, accompanied by double bond migration. The epimerase OpaE changes the d-Phe residue back to l-form, which is essential for the final methylation by OpaF.



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