SYNTHÈSES DE DÉRIVÉS DE LA LYSINE

1962 ◽  
Vol 40 (8) ◽  
pp. 1626-1631 ◽  
Author(s):  
Louis-Marie Babineau ◽  
Louis Berlinguet
Keyword(s):  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Barium Hydroxide ◽  
Primary Amines ◽  
Gaseous Ammonia ◽  
Hydrolysis Of

New N-ε-substituted lysines have been synthetized as follows: by condensing 5-δ-bromobutylhydantoin with different primary amines, 5-δ-alkylaminobutylhydantoins were obtained, the alkaline hydrolysis of which gave the corresponding N-ε-substituted lysines. N-α-Substituted hexahomoserines have also been prepared by acid hydrolysis of the reaction product between α,ε-dihydroxycaproic nitrile and primary amines. 5-Amino-5-carboxypentane sulphonamide has been prepared in the following way: 5-δ-bromobutylhydantoin was reacted with thiourea, and the resulting isothiouronium salt was oxidized with chlorine. Gaseous ammonia was then bubbled through an ethereal suspension of the 5-δ-chlorosulphonyl butylhydantoin and the resulting sulphonamide was hydrolyzed under pressure with barium hydroxide. 5-Amino-5-carboxypentane sulphonamide was then isolated and crystallized.

Kinetic Study of Hydrolysis of Benzoates. Part XXV. Ortho Substituent Effect in Alkaline Hydrolysis of Phenyl Esters of Substituted Benzoic Acids in Water

2006 ◽  
Vol 71 (1) ◽  
pp. 107-128 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Vahur Mäemets ◽  
Ilmar Koppel
Keyword(s):  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Substituent Effect ◽  
Ethyl Esters ◽  
Benzoic Acids ◽  
Neat Water ◽  
Substituted Benzoic Acids ◽  
Hydrolysis Of Esters ◽  
Hydrolysis Of

The second-order rate constants k2 for alkaline hydrolysis of phenyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2C6H5 (X = H, 3-Cl, 3-NO2, 3-CH3, 4-NO2, 4-Cl, 4-F, 4-CH3, 4-OCH3, 4-NH2, 2-NO2, 2-CN, 2-F, 2-Cl, 2-Br, 2-I, 2-CH3, 2-OCH3, 2-CF3, 2-NH2), and of substituted phenyl esters of benzoic acid, C6H5CO2C6H4-X (X = 2-I, 2-CF3, 2-C(CH3)3, 4-Cl, 4-CH3, 4-OCH3, 4-NH2), have been measured spectrophotometrically in water at 25 °C. The substituent effect in alkaline hydrolysis of phenyl esters of para-substituted benzoic acids, similar to that for ethyl esters of para-substituted benzoic acids, was found to be precisely described by the Hammett relationship (ρ = 1.7 in water). The log k value for alkaline hydrolysis of phenyl and ethyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2R, was nicely correlated with log km,p,ortho = log ko + (ρ)m,pσ + (ρI)orthoσI + (ρ°R)orthoσ°R + δorthoEsB where σ, σI, σ°R are the Hammett polar, Taft inductive and Taft resonance (σ°R = σ° - σI) substituent constants, respectively. EsB is the steric scale for ortho substituents calculated on the basis of the log k values for the acid hydrolysis of ortho- substituted phenyl benzoates in water owing to the ortho substituent in the phenyl of phenyl benzoates. In water, the main factors responsible for changes in the ortho substituent effect in alkaline hydrolysis of phenyl and ethyl esters of ortho-substituted benzoic acids, X-C6H4CO2R, were found to be the inductive and steric factors while the role of the resonance term was negligible ((ρ°R)ortho ca. 0.3). In alkaline hydrolysis of substituted benzoates in neat water, the ortho inductive effect appeared to be 1.5 times and steric influence 2.7 times higher than the corresponding influences from the ortho position in the phenyl of phenyl benzoates. The contributions of the steric effects in alkaline hydrolysis of esters of ortho-substituted benzoic acids was found to be approximately the same as in acid hydrolysis of esters of ortho-substituted benzoic and acid esterification of ortho-substituted benzoic acids.

scholarly journals The formation of lipid-linked sugars by cell-free preparations of lactating rabbit mammary gland

1978 ◽  
Vol 170 (3) ◽  
pp. 479-486 ◽  
Author(s):  
D A White
Keyword(s):  
Mammary Gland ◽  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Gel Electrophoresis ◽  
Incubation Medium ◽  
Polyacrylamide Gel Electrophoresis ◽  
Protein Fractions ◽  
Exogenous Substrate ◽  
Major Species ◽  
Hydrolysis Of

1. A lactating rabbit mammary-gland microsomal system catalysed the incorporation of mannose from GDP-[U-14C]mannose into three endogenous acceptors, (i) polyprenyl phosphate mannose, (ii) lipid-linked oligosaccharide and (iii) protein. 2. Synthesis of polyprenyl phosphate mannose was stimulated by addition of dolichol phosphate to the incubation medium and was reversed by addition of GDP. The product had properties identical with those of authentic dolichol phosphate mannose. 3. The oligosaccharides derived from acid hydrolysis of the lipid-linked oligosaccharide fraction were of six, eight and nine to ten monosaccharide units, the octasaccharide being the major species formed. The oligosaccharide appeared to be attached to the lipid via a pyrophosphate bridge, since strong alkaline hydrolysis liberated an oligosaccharide phosphate. 4. Polyprenyl phosphate mannose served as a mannose donor to lipid-linked oligosaccharides and protein. When added as exogenous substrate it gave rise to a lipid-linked oligosaccharide of about six units. 5. Incorporation of radioactivity in protein was low, but polyacrylamide-gel electrophoresis of the protein fractions indicated that polypeptides of mol.wts. 115000, 75000 and 33000 were labelled.

Ribonucleosides of 3-amino- and 3,5-diaminopyrazole-4-carboxylic acid and their open-chain analogues: Synthesis and reactions

1986 ◽  
Vol 51 (7) ◽  
pp. 1512-1531 ◽  
Author(s):  
Maria K. Spassova ◽  
Antonín Holý ◽  
Milena Masojídková
Keyword(s):  
Carboxylic Acid ◽  
Acid Hydrolysis ◽  
Carboxylic Acids ◽  
Sodium Salt ◽  
Alkaline Hydrolysis ◽  
Trimethylsilyl Derivative ◽  
Open Chain ◽  
Silyl Derivatives ◽  
Hydrolysis Of

Bis(trimethylsilyl) derivative of ethyl 3-aminopyrazole-4-carboxylate (VI) and tris(trimethylsilyl) derivative of ethyl 3,5-diaminopyrazole-4-carboxylate (VII) on reaction with 2,3,5-tri-O-benzoyl-D-ribofuranolyl chloride and subsequent debenzoylation afforded the respective β-D-ribofuranosyl derivatives VIIIa and Xa. Their alkaline hydrolysis led to 1-(β-D-ribofuranosyl)-3-aminopyrazole-4-carboxylic acid (VIIIc) and 1-(β-D-ribofuranosyl)-3,5-diaminopyrazole-4-carboxylic acid (Xb). The esters VIIIa and Xa were not ammonolyzed under normal conditions. Contrary to nucleosidation of the silyl derivatives VI and VII, sodium salt of ethyl 3-aminopyrazole-4-carboxylate was alkylated with 4-chloromethyl-2,2-dimethyl-1,3-dioxolane (XI) or 5-(p-toluenesulfonyloxy)-1,3-dioxane (XVIIb) to give a mixture of the N-isomeric derivatives XIIIa, XIXa and XIIa, XVIIIa, respectively; sodium salt of the 3,5-diamino derivative V reacted with these synthons under formation of the corresponding compounds XIIIb and XXa. Subsequent alkaline and acid hydrolysis of XIIa and XIIIb gave the open-chain analogs of nucleosides XV and XVI. The N-(1,3-dioxan-5-yl) derivatives XVIIIc and XXa resisted acid hydrolysis, giving rise only to carboxylic acids XVIIIb and XXb.

scholarly journals 1-(O-β-Glucosaminyl)-2,3-diglyceride in Bacillus megaterium

1972 ◽  
Vol 126 (3) ◽  
pp. 499-502 ◽  
Author(s):  
P. J. R. Phizackerley ◽  
J. C. MacDougall ◽  
R. A. Moore
Keyword(s):  
Fatty Acids ◽  
Acid Hydrolysis ◽  
Bacillus Megaterium ◽  
Total Lipid ◽  
Alkaline Hydrolysis ◽  
Partial Acid Hydrolysis ◽  
Molar Proportion ◽  
Ester Linkage ◽  
Hydrolysis Of

1. A lipid that contains glucosamine but not phosphorus has been isolated from Bacillus megaterium. It constitutes about 5% of the total lipid glucosaminide in this organism and can be distinguished chromatographically from 2′-(O-β-glucosaminyl)phosphatidylglycerol and 3′-(O-β-glucosaminyl)phosphatidylglycerol, which are also present. 2. The lipid contains glycerol, fatty acids and glucosamine in the molar proportion 1:2:1. The fatty acids are bound by an ester linkage and are similar to those found in other lipids of this organism. Partial acid hydrolysis or alkaline hydrolysis of the lipid yields 1-(O-β-glucosaminyl)glycerol and degradation with nitrite yields 2,5-anhydromannose and diglyceride. 3. The lipid has been identified as 1-(O-β-glucosaminyl)-2,3-diglyceride.

Synthesis of N4-Amino and N4-Hydroxy Derivatives of 5-Azacytidine. A Facile Rearrangement of the N4-Amino Derivative to 5-(3-β-D-Ribofuranosylureido)-1H-1,2,4-triazole

2004 ◽  
Vol 69 (4) ◽  
pp. 905-917 ◽  
Author(s):  
Alois Pískala ◽  
Naeem B. Hanna ◽  
Milena Masojídková ◽  
Pavel Fiedler ◽  
Ivan Votruba
Keyword(s):  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Hydroxylamine Hydrochloride ◽  
Amino Derivative ◽  
Cytostatic Activity ◽  
Thermal Rearrangement ◽  
Water Solutions ◽  
Hydrolysis Of ◽  
Derivatives Of

Treatment of methoxyribosyltriazinone 4 with hydrazine in methanol afforded crude 4-hydrazino-1-β-D-ribofuranosyl-1,3,5-triazin-2(1H)-one (N4-amino-5-azacytidine) (2), which rearranged rapidly to isomeric 5-ribosylureidotriazole 6. The rearrangement proceeds easily also in water solutions of 2. Alkaline hydrolysis of 6 gave a mixture of 5-ureidotriazole 7 and 5-aminotriazole 8. Acid hydrolysis of 6 afforded only 7. This compound was also prepared by thermal rearrangement of 5-amino-1-carbamoyltriazole 9 or on reaction of cyano(formyl)guanidine 10 with hydrazine hydrochloride. Treatment of benzoylated methoxyribosyltriazinone 4a with hydrazine in methanol gave only the rearranged product 6a. Reaction of tribenzoylribosyl isocyanate 12 with aminotriazole 8 gave 1-triazolecarboxamidotribenzoylribose 13, which afforded by methanolysis oxazoloribofuranose 14 and aminotriazole 8. Compound 14 was also obtained by methanolysis of blocked ribosylcarbamate 16. Reaction of methoxyribosyltriazinone 4 with hydroxylamine in methanol afforded 4-hydroxylamino-1-β-D-ribofuranosyl-1,3,5-triazin-2(1H)-one (N4-hydroxy-5-azacytidine) (3), which on the action of excess hydroxylamine yielded 1-cyano-1-hydroxy-5-β-D-ribofuranosylisobiuret (19). Treatment of methoxy-1,3,5-triazinone 18 with a solution of hydroxylamine in methanol gave 4-hydroxylamino-1-methyl-1,3,5-triazin-2(1H)-one (N4-hydroxy-1-methyl-5-azacytosine) (17). Heating of cyano(formyl)guanidine 10 with hydroxylamine hydrochloride in water lead to the formation of triuret (21). The mechanisms of the reactions of methoxyribosyltriazinone 4 with hydrazine and hydroxylamine are discussed. Compounds 2, 6 and 19 exhibited no significant antibacterial or cytostatic activity.

Total Synthesis of DL-Glucose, 3-O-Methyl-DL-glucose, and 3-Deoxy-DL-ribo-hexopyranose from 1,6:3,4-Dianhydro-β-DL-allo-hexopyranose, a Product Obtained from Acrolein Dimer

1971 ◽  
Vol 49 (20) ◽  
pp. 3342-3347 ◽  
Author(s):  
U. P. Singh ◽  
R. K. Brown
Keyword(s):  
Total Synthesis ◽  
Acid Hydrolysis ◽  
Sodium Methoxide ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Barium Hydroxide ◽  
Lithium Aluminum ◽  
Methyl Glycoside ◽  
Acid Catalyzed ◽  
Hydrolysis Of

The reaction of butyllithium in ether with 1,6:2,3-dianhydro-4-deoxy-β-DL-ribo-hexopyranose (1), a substance obtained in five steps from acrolein dimer, gave 1,6-anhydro-3,4-dideoxy-β-DL-erythro-hex-3-enopyranose (2). The compound 1,6:3,4-dianhydro-β-DL-allo-hexopyranose (3), obtained from 2, was converted by reaction with aqueous barium hydroxide followed by hydrolysis of the product, to DL-glucose 5. Treatment of 3 with sodium methoxide in methanol followed by acid hydrolysis of the 1,6-anhydro intermediate 6, gave 3-O-methyl-DL-glucose (7). The same intermediate, 6, along with the methyl glycoside 8, could be obtained by the acid-catalyzed reaction of 3 with methanol. Lithium aluminum hydride reacted with 3 to form 1,6-anhydro-3-deoxy-β-DL-ribo-hexopyranose (9), which was hydrolyzed readily to 3-deoxy-DL-ribo-hexopyranose (10).Yields were excellent throughout. All products obtained from the oxirane 3 were those resulting only from trans diaxial opening of the oxirane ring.

Hydrolysis of amides. II. Substituent effects in dilute acid and alkali

1966 ◽  
Vol 19 (6) ◽  
pp. 1013 ◽  
Author(s):  
PD Bolton
Keyword(s):  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Substituent Effects ◽  
Type Equation ◽  
Dilute Acid ◽  
Reaction Series ◽  
Dilute Acid Hydrolysis ◽  
Similar Series ◽  
Hydrolysis Of

Energies and entropies of activation for the hydrolysis in dilute acid of six aliphatic amides are reported. These results, in conjunction with those of other workers, indicate the dilute acid hydrolysis of primary aliphatic amides to be governed by a combination of steric and hyperconjugative substituent effects and to be independent of polar effects. The reaction series is well correlated by the Taft-type equation �������������� logk = 0.858 EC/S-0.493(n-3)+logk0 in which EC/S denotes a pure steric substituent parameter and n is the number of α-hydrogens in the substituent. The alkaline hydrolysis of a similar series of amides is well correlated by the equation ������������ log k = 2.05�*+ 1.08 EC/S -O.743(n-3)+ log ko.

THE HYDROLYSIS OF PHOSPHATE DIESTERS WITH BARIUM HYDROXIDE

1955 ◽  
Vol 33 (4) ◽  
pp. 705-710 ◽  
Author(s):  
C. W. Helleiner ◽  
G. C. Butler
Keyword(s):  
Sodium Hydroxide ◽  
Alkaline Hydrolysis ◽  
Small Proportion ◽  
Inorganic Phosphate ◽  
Barium Hydroxide ◽  
Phosphate Ester ◽  
Purine Nucleotides ◽  
Diphenyl Phosphate ◽  
Phosphate Diesters ◽  
Hydrolysis Of

The rate of alkaline hydrolysis of diphenyl phosphate has been found to be increased by the presence of barium. Similarly, desoxyribonucleate (DNA), which is not hydrolyzed rapidly by hot sodium hydroxide, is hydrolyzed by barium hydroxide. Only a very small proportion of the total phosphorus of either diphenyl phosphate or DNA is converted to inorganic phosphate during this hydrolysis. In addition to hydrolysis of the phosphate ester bonds of DNA, hot alkali also causes the deamination of desoxycytidylic acid residues and probably of the amino-purine nucleotides as well.

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