Synthesis of Normuramic Acid Carba Analog and Its Glycopeptide Derivative Resistant to β-Elimination Splitting of the Side Chain

2000 ◽  
Vol 65 (11) ◽  
pp. 1726-1736 ◽  
Author(s):  
Miroslav Ledvina ◽  
Radka Pavelová ◽  
Anna Rohlenová ◽  
Jan Ježek ◽  
David Šaman

Carba analogs of normuramic acid, i.e., 3-(benzyl 2-acetamido-2,3-dideoxy-4,6-O-isopropylidene-α-D-glucopyranosid-3-yl)propanoic acid derivatives (nitrile or esters) 3a-3c were prepared by addition of radicals generated from benzyl 2-acetamido-2-deoxy-4,6-O-isopropylidene-3-O-[(methylsulfanyl)thiocarbonyl]- (2a) or -3-O-(phenoxythiocarbonyl)-α-D-glucopyranoside (2b) with Bu3SnH to acrylonitrile or acryl esters. Alkaline hydrolysis of ethyl ester 3c afforded 3-(benzyl 2-acetamido-2,3-dideoxy-4,6-O-isopropylidene-α-D-glucopyranosid-3-yl)propanoic acid (5). Coupling of acid 5 with L-2-aminobutanoyl-D-isoglutamine benzyl ester trifluoroacetate and subsequent deprotection of the intermediate 6 furnished N-[3-(2-acetamido-2,3-dideoxy-α-D-glucopyranosid-3-yl)propanoyl]-L-2-aminobutanoyl-D-isoglutamine (7).

Pteridines ◽  
1990 ◽  
Vol 2 (3) ◽  
pp. 133-139 ◽  
Author(s):  
Andre Rosowsky ◽  
Ronald A. Forsch ◽  
Richard G. Moran ◽  
James H. Freisheim

Summaryβ,γ-Methano derivatives of methotrexate (MTX) and aminopterin (AMT) were synthesized with the aim of assessing the effect of this side-chain modification on dihydrofolate reductase (OHFR) inhibition, folylpolyglutamate synthetase (FPGS) inhibition, and tumor cell growth inhibition. Mixed carboxylic-carbonic anhydride (MCA) coupling of 4-amino-4-deoxy-N10-methylpteroic acid (mAPA) and dimethyl trans-α-(2-carboxycyclopropyl) glycinate, followed by alkaline hydrolysis, afforded N-( 4-amino-4-deoxy-N10-methylpteroyl)-α-( trans-2-carboxycyclopropyl)glycine (β,γ-methanoMTX) as a mixture of the four possible diastereomers with trans substitution on the cyclopropane ring. N-(4-Amino-4-deoxypteroyl)-trans-α.-(2-carboxycyclopropyl) glycine (β,γ-methanoAMT) , also as a diastereomer mixture, was obtained from 4-amino-4-deoxy-N10 - formylpteroic acid (fAPA) and dimethyl trans-α-(2-carboxycyclopropyl)-glycinate by MCA coupling and alkaline hydrolysis of the ester and N10-formyl groups. β,γ-MethanoMTX and β,γ-methanoAMT may be viewed as MTX and AMT analogues with a conformationally restricted side chain. In vitro biological activity data for these novel compounds support the view that the active site of DHFR, already known for its ability to tolerate modification of the γ-carboxyl group of MTX and AMT, can likewise accommodate substitution on the β- and γ-carbons.


2019 ◽  
Vol 73 (10) ◽  
pp. 2461-2468 ◽  
Author(s):  
Xin Yuan ◽  
Panliang Zhang ◽  
Guangyong Liu ◽  
Weifeng Xu ◽  
Kewen Tang

1987 ◽  
Vol 52 (11) ◽  
pp. 2801-2809 ◽  
Author(s):  
Antonín Holý ◽  
Ivan Rosenberg

Diethyl 2-hydroxyethoxymethanephosphonate (VIII) was converted into diethyl 2-halogenoethoxymethanephosphonates IXa and IXb by reaction with triphenylphosphine and tetrachloromethane or tetrabromomethane; analogous reaction of VIII with p-toluenesulfonyl chloride afforded diethyl 2-(p-toluenesulfonyloxy)ethoxymethanephosphonate (IXc). Reaction of sodium salt of adenine with compounds IX led to 9-(2-diethoxyphosphonylmethoxyethyl)adenine (X). Compound X was converted into 9-(2-phosphonylmethoxyethyl)adenine (II) by treatment with bromotrimethylsilane whereas alkaline hydrolysis of X gave ethyl ester Vb. Reaction of 9-(2-hydroxyethyl)adenine (IIIa) or its N6-benzoyl derivative IIIb with dimethyl p-toluenesulfonyloxymethanephosphonate (IV) in the presence of sodium hydride, followed by alkaline hydrolysis yielded methyl ester Va. Morpholide XI reacted with an inorganic phosphate and diphosphate to give 9-(2-phosphorylphosphonylmethoxyethyl)adenine (XII) and 2-(diphosphorylphosphonylmethoxyethyl)adenine (XIII), respectively.


1980 ◽  
Vol 45 (11) ◽  
pp. 2873-2882
Author(s):  
Vladislav Holba ◽  
Ján Benko

The kinetics of alkaline hydrolysis of succinic acid monomethyl and monopropyl esters were studied in mixed aqueous-nonaqueous media at various temperatures and ionic strengths. The results of measurements are discussed in terms of electrostatic and specific interactions between the reactants and other components of the reaction mixture. The kinetic parameters in the media under study are related to the influence of the cosolvent on the solvation sphere of the reactants.


2009 ◽  
Vol 74 (1) ◽  
pp. 29-42 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Signe Vahur ◽  
Oksana Travnikova ◽  
Ilmar A. Koppel

The second-order rate constants k (in dm3 mol–1 s–1) for alkaline hydrolysis of phenyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2C6H5, have been measured spectrophotometrically in aqueous 0.5 and 2.25 M Bu4NBr at 25 °C. The substituent effects for para and meta derivatives were described using the Hammett relationship. For the ortho derivatives the Charton equation was used. For ortho-substituted esters two steric scales were involved: the EsB and the Charton steric (υ) constants. When going from pure water to aqueous 0.5 and 2.25 M Bu4NBr, the meta and para polar effects, the ortho inductive and resonance effects in alkaline hydrolysis of phenyl esters of substituted benzoic acids, became stronger nearly to the same extent as found for alkaline hydrolysis of C6H5CO2C6H4-X. The steric term of ortho-substituted esters was almost independent of the media considered. The rate constants of alkaline hydrolysis of ortho-, meta- and para-substituted phenyl benzoates (X-C6H4CO2C6H5, C6H5CO2C6H4-X) and alkyl benzoates, C6H5CO2R, in water, 0.5 and 2.25 M Bu4NBr were correlated with the corresponding IR stretching frequencies of carbonyl group, (ΔνCO)X.


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