512. Amination and acylation reactions by homocysteine thiolactone and N-benzyloxycarbonylhomocysteine thiolactone

Laliberté, Réal; Knobler, Y.; Fränkel, Max

doi:10.1039/jr9630002756

Cited by 5 publications

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“…The results showed the higher reactivity of O-lactone as compared with the S-lactone, and the deactivation of the N-benzyloxycarbonyl derivative as compared with the respective N-benzoyl lactone (see Table II). The findings are in agreement with previous investigations about amide formation from 0-and S-lactones [6). Compared with O-lactone, the deactivation of S-lactone must be attributed to the stronger nucleophilicity of the mercaptide anion, which is a poorer leaving group than the alkoxide.…”

Section: Reaction Of N-acyl-dl-homocysteine Thiolactone With Hydroxylsupporting

confidence: 93%

“…Bis-a-Nrbenz oyl-DL-homocystinedihydroxamic acid (IIlb). a-Be nz amido--y-thiobutyr-olactone [6] (2.5 g, 0.114 mole) was added to a solution of hydroxylamine hydrochloride (3.4 g, 0.049 mole) in ethanol (15 ml ). Sodium hydroxide (1.85 g, 0.046 mole) in ethanol (15 ml) was added with cooling and the mixture was then stirred at room temperature for 36 hr.…”

Section: Dl-homocystinedihydroxamic Acidmentioning

confidence: 99%

“…Bis-a-N-benzyloxycarbonyl-DL-homocystinedihydroxamic aicd (HIe). N-Benzyloxycarbonyl-DL-homocysteine thiolactone [6] (5.03 g, 0.02 mole) was stirred with hydroxylamine hydrochloride (4.2 g, 0.06 mole) in ethanol (30 ml). The mixture was cooled to 0°and sodium hydroxide (2.4 g, 0.06 mole) in ethanol (20 ml) was added.…”

Section: Dl-homoserinehydroxamic Acid and «-Nr Acyl Derivatives O-ammentioning

confidence: 99%

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DL‐homoserinehydroxamic Acid, DL‐homo‐cystinedihydroxamic Acid, and Derivatives by Hydroxylaminolysis of γ‐Hydroxy‐ and γ‐Thio‐Lactones

Knobler

Bittner

Fränkel

1970

Israel Journal of Chemistry

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The reaction of a-amino-, a-carbamoylamino-, a-benzamido-, and a -benzyloxycarbonylamino-y-buryrolactone with hydroxylamine led to the formation of DL-homoserinehydroxamic acid and a -N-acyl derivatives. a-N-Benzoyl-DL-homoserine-N-methyl-hydroxamic acid and 0-benzylhydroxamic acid ester were prepared by reacting a-benz amido-y -butyrolactone with N-methylhydroxylamine and with O-benzylhydroxylamine, respectively. Hydroxylaminolysis of DL-homocysteinethiolactone and of N-acyl-DL-homocysteinethiolacrones gave homocystinedihydroxamic acid and N,N'-disubstiruted derivatives. Relative reactivities of 0-and S-lacrones were compared. a -Amino hydroxamic acids have been prepared by the procedure known for other hydroxamic acids, from a -arnino acid esters and hydroxylamine in alcoholic solution [1]. An additional general method of obtaining a-amino hydroxamic acids is to react a-amino-acid N-carboxyanhydrides with hydroxylamine hydrochloride [2]. The preparation of a-amino l3-functional hydroxamic acids was developed during work on syntheses of the antibiotic cycloserine (oxamycin), an a-amino-l3-hydroxy cyclic hydroxamic acid ester (D-4-amino-3-isoxazolidinone) [3].We considered a-amino--y-butyrolactone (homoserine lactone) and a-amino--y-thiobutyrolactone (homocyste ine lactone) appropriate for the synthesis of o-arnino-v-hydr-o xy-and a-amino--y-thio-butyrhydroxamic acids. Hydroxylaminolysis of a-amino-and a-acylamino-rt-butyrolactoneo-Amino-, a-carbamoylamino-, c-benz amido-, and a-benzyloxycarbonylarnino-v-butyr-o lac tone were brought to reaction with ethanolic hydroxylamine. The reaction was carried out at room temperature, the mixtures being kept for 24 hr. The hydroxamic acids precipitated from the reaction mixture, or were obtained after removal of the solvent and recrystallisation from ethanol-water or propan-2-ol (see Table I) .

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Section: Reaction Of N-acyl-dl-homocysteine Thiolactone With Hydroxylsupporting

confidence: 93%

Section: Dl-homocystinedihydroxamic Acidmentioning

confidence: 99%

Section: Dl-homoserinehydroxamic Acid and «-Nr Acyl Derivatives O-ammentioning

confidence: 99%

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DL‐homoserinehydroxamic Acid, DL‐homo‐cystinedihydroxamic Acid, and Derivatives by Hydroxylaminolysis of γ‐Hydroxy‐ and γ‐Thio‐Lactones

Knobler

Bittner

Fränkel

1970

Israel Journal of Chemistry

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“…Even though thiolactone 4 is known to react with amines (such as lysine residues) [9,27], it might be less electrophilic than linear thioesters, as it has been reported for a similar example [28]. However, when we mixed 4 in water (at pH 6) with various amino acids, no amide bond formation was detected.…”

Section: Resultsmentioning

confidence: 83%

Chemistry of Homocysteine Thiolactone in A Prebiotic Perspective

Shalayel

Vallée

2019

Life

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Homocysteine is a non-proteinogenic sulfur-containing amino acid. Like cysteine, it can form disulfide bridges and complex metallic cations. It is also closely related to methionine, the first amino acid in the synthesis of all contemporary proteins. Furthermore, its cyclized form, a five-membered ring thiolactone, is stable in acidic and neutral water. Here, we demonstrate that this thiolactone may have been formed in the primitive ocean directly from the Strecker precursor of homocysteine, an aminonitrile. Even though it is poorly reactive, this thiolactone may be open by some amines, yielding amides which, in turn, could be the precursors of longer peptides.

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“…Because the intrinsic instability of the neutral homocysteine-γ-thiolactone 1 leads to the formation of the corresponding diketopiperazine adduct [79], an efficient reaction between the amino group in the α-position and an electrophile is mandatory, eventually leading to the targeted monomer or initiator. Amidation reactions are most frequently used: conjugation with acid halides [80][81][82][83], (in situ) activated carboxylic acids [83][84][85][86][87][88][89], and anhydrides [90] enables the synthesis of homocysteine-γ-thiolactone derivatives. A carbamate linkage is formed by treatment with chloroformates [91].…”

Section: Reactivity and Synthetic Use Of Homocysteine-γ-thiolactone Amentioning

confidence: 99%

One-Pot Double Modification of Polymers Based on Thiolactone Chemistry

Espeel

Prez

2014

Multi-Component and Sequential Reactions in Polymer Synthesis

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One-pot multistep reactions based on thiolactone chemistry have emerged as a powerful tool for modifying thiolactone-containing polymers in one-pot and in an elegant manner. In general, thiolactones can be opened by a wide variety of functional amines and the released thiol can react with thiol 'scavengers' of choice. This overview highlights the most important features of this approach, illustrated by the versatile and site-specific double postpolymerization modification of various reactive systems.

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512. Amination and acylation reactions by homocysteine thiolactone and N-benzyloxycarbonylhomocysteine thiolactone

Cited by 5 publications

References 0 publications

DL‐homoserinehydroxamic Acid, DL‐homo‐cystinedihydroxamic Acid, and Derivatives by Hydroxylaminolysis of γ‐Hydroxy‐ and γ‐Thio‐Lactones

DL‐homoserinehydroxamic Acid, DL‐homo‐cystinedihydroxamic Acid, and Derivatives by Hydroxylaminolysis of γ‐Hydroxy‐ and γ‐Thio‐Lactones

Chemistry of Homocysteine Thiolactone in A Prebiotic Perspective

One-Pot Double Modification of Polymers Based on Thiolactone Chemistry

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