4515-23-5

Usage

Uses

Used in Organic Synthesis:
N-Carbobenzyloxy-L-aspartic anhydride is used as a protective agent for the carboxyl group of amino acids, which is crucial for the successful synthesis of peptides in organic chemistry. This protection allows for selective reactions to occur at other sites on the amino acid without affecting the carboxyl group.
Used in Peptide Chemistry:
In peptide chemistry, N-Carbobenzyloxy-L-aspartic anhydride is used as a reagent to create esters and amides of aspartic acid derivatives. This functionality is essential for the preparation and modification of peptides, enabling the development of novel peptide-based compounds with specific biological activities.
Used in Pharmaceutical Development:
N-Carbobenzyloxy-L-aspartic anhydride plays a significant role in the pharmaceutical industry, where it aids in the synthesis of peptide-based drugs. Its ability to protect and modify the carboxyl group of amino acids contributes to the development of more effective and targeted therapeutic agents.
Used in Research Laboratories:
In academic and industrial research settings, N-Carbobenzyloxy-L-aspartic anhydride is employed for the study of peptide synthesis and the exploration of new methods for the protection and modification of amino acids. This research contributes to the advancement of peptide chemistry and the discovery of new bioactive compounds.
Overall, N-Carbobenzyloxy-L-aspartic anhydride is a versatile compound in the fields of organic synthesis, peptide chemistry, pharmaceutical development, and research, where its applications contribute to the advancement of scientific knowledge and the creation of novel therapeutic agents.

InChI:InChI=1/C12H11NO5/c14-10-6-9(11(15)18-10)13-12(16)17-7-8-4-2-1-3-5-8/h1-5,9H,6-7H2,(H,13,16)/t9-/m0/s1

Synthetic route

N-Cbz-L-Asp (1152-61-0) → N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5)

Conditions	Yield
	100%
With dicyclohexyl-carbodiimide In ethyl acetate 1.) 1 h, 0 deg C, 2.) 24 h, r.t.;	98%
With acetic anhydride for 0.0166667h; microwave irradiation;	98%

N-Cbz-L-Asp (1152-61-0) → benzyl N-[(3R)-2,5-dioxotetrahydrofuran-3-yl]carbamate (75443-62-8) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5)

Conditions	Yield
With acetic anhydride at 20 - 45℃; for 2.25h; Product distribution; Further Variations:; Reagents; Solvents; Temperatures;

benzyl chloroformate (501-53-1) → N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: 89 percent 2: 98 percent / dicyclohexylcarbodiimide / ethyl acetate / 1.) 1 h, 0 deg C, 2.) 24 h, r.t. View Scheme
Multi-step reaction with 2 steps 1: K2CO3 / H2O / Ambient temperature 2: Ac2O / acetic acid / Ambient temperature View Scheme
Multi-step reaction with 2 steps 1: K2CO3 / H2O 2: Ac2O / acetic acid View Scheme

benzyl alcohol (100-51-6) → N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5)

Conditions	Yield
Multi-step reaction with 3 steps 1: toluene / anfangs unter Kuehlung 2: MgO; water; diethyl ether 3: acetic acid anhydride View Scheme

n-Dodecylamine (124-22-1) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-dodecyl-2-carbobenzyloxyaminosuccinamic acid

Conditions	Yield
With triethylamine In dichloromethane for 12h;	97%
With triethylamine In dichloromethane for 12h;	97%

N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → benzyl (3S)-5-oxotetrahydro-3-furanylcarbamate (87219-29-2)

Conditions	Yield
With sodium tetrahydroborate In tetrahydrofuran	91%
With sodium tetrahydroborate at 0℃; for 3h;	91%
With sodium tetrahydroborate	86%

aniline (62-53-3) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → benzyloxycarbonyl-L-aspartic acid dianilide (685139-81-5)

Conditions	Yield
Stage #1: N-benzyloxycarbonyl-L-aspartic acid anhydride In dimethyl sulfoxide at 20℃; for 3h; Stage #2: aniline With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In N,N-dimethyl-formamide at 20℃; for 24h;	87%
Stage #1: N-benzyloxycarbonyl-L-aspartic acid anhydride In N,N-dimethyl-formamide at 20℃; for 3h; Stage #2: aniline With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In N,N-dimethyl-formamide at 20℃; for 24h;	87%

3-methyl-1,2,4-thiadiazol-5-amine (17467-35-5) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → 2-benzyloxycarbonylamino-N-(3-methyl-[1,2,4]thiadiazol-5-yl)-succinamic acid (403736-43-6)

Conditions	Yield
In dimethyl sulfoxide at 20℃; for 2h;	85%

benzyl alcohol (100-51-6) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → Z-Asp-OBn (4779-31-1)

Conditions	Yield
at 90℃; for 3.5h;	82%
at 90℃; for 3.5h;	72%

ethanol (64-17-5) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-3-(benzyloxycarbonylamino)-4-ethoxy-4-oxobutanoic acid (4668-43-3)

Conditions	Yield
at 20℃; for 36h;	81%
Heating;
With N-cyclohexyl-cyclohexanamine In diethyl ether
for 18h; Product distribution / selectivity; Heating / reflux;

3,4-dimethoxyaniline (6315-89-5) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → [1,2-bis-(3,4-dimethoxy-phenylcarbamoyl)-ethyl]-carbamic acid benzyl ester (932743-84-5)

Conditions	Yield
With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In N,N-dimethyl-formamide at 20℃; for 24h;	79%

N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (3S)-benzyl N-(1-hydroxy-2,5-dioxo-pyrrolidin-3-yl)carbamate

Conditions	Yield
Stage #1: N-benzyloxycarbonyl-L-aspartic acid anhydride With sodium hydroxide; hydroxylamine hydrochloride In 1,4-dioxane; water at 19.85 - 49.85℃; for 1.25h; Stage #2: at 124.85℃; for 0.333333h;	77%
With sodium hydroxide; hydroxylamine hydrochloride In 1,4-dioxane; water at 60℃; for 2h;	75%
With hydroxylamine hydrochloride; sodium carbonate In water at 0℃; for 1h;	54%

benzylamine (100-46-9) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-(1-benzyl-2,5-dioxo-pyrrolidin-3-yl)carbamic acid benzyl ester (124166-11-6)

Conditions	Yield
toluene-4-sulfonic acid In DMF (N,N-dimethyl-formamide); toluene at 22 - 110℃; for 31h; Heating / reflux; Azeotropic dehydratation;	77%
toluene-4-sulfonic acid In DMF (N,N-dimethyl-formamide); toluene at 30 - 110℃; for 25h; Heating / reflux;	n/a
In ethanol at 20℃; for 18h;	n/a

4-tert-Butylaniline (769-92-6) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → [1,2-bis-(4-tert-butyl-phenylcarbamoyl)-ethyl]-carbamic acid benzyl ester (918309-76-9)

Conditions	Yield
With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In N,N-dimethyl-formamide at 20℃; for 25h;	73%

O-benzylhydoxylamine hydrochloride (2687-43-6) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → ((S)-1-Benzyloxy-2,5-dioxo-pyrrolidin-3-yl)-carbamic acid benzyl ester

Conditions	Yield
In toluene for 1h; Heating;	72%

N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-benzyloxycarbonyl-L-aspartic acid α-p-nitrobenzyl ester (4668-44-4)

Conditions	Yield
	69%

p-toluidine (106-49-0) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-3-Benzyloxycarbonylamino-N-p-tolyl-succinamic acid + (S)-2-Benzyloxycarbonylamino-N-p-tolyl-succinamic acid

Conditions	Yield
With acetic acid In benzene for 0.166667h; Heating; Yields of byproduct given;	A 67% B n/a
In dimethyl sulfoxide for 0.333333h; Ambient temperature; Yield given. Yields of byproduct given;

4-methoxy-aniline (104-94-9) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → [(S)-1,2-Bis-(4-methoxy-phenylcarbamoyl)-ethyl]-carbamic acid benzyl ester

Conditions	Yield
Stage #1: N-benzyloxycarbonyl-L-aspartic acid anhydride In N,N-dimethyl-formamide at 20℃; for 3h; Stage #2: 4-methoxy-aniline With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In N,N-dimethyl-formamide at 20℃; for 24h;	60%

methanol (67-56-1) + (3-methoxyphenyl)magnesium bromide (36282-40-3) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (3S)-methyl 3-(benzyloxycarbonylamino)-4-(3-methoxyphenyl)-4-oxobutanoate + dimethyl (2S)-2-[(phenylmethoxy)carbonylamino]-butane-1,4-dioate (35909-93-4)

Conditions	Yield
Stage #1: (3-methoxyphenyl)magnesium bromide; N-benzyloxycarbonyl-L-aspartic acid anhydride In tetrahydrofuran at -78℃; for 4h; Stage #2: With citric acid In tetrahydrofuran at -78 - 20℃; Stage #3: methanol With thionyl chloride	A 60% B n/a

N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (3S)-3-benzyloxycarbonylamino-4-hydroxybutanoic acid (94664-82-1)

Conditions	Yield
With sodium tetrahydroborate In tetrahydrofuran for 1h; Ambient temperature;	59%
Multi-step reaction with 2 steps 1: NaBH4 / tetrahydrofuran / 16 h / 20 °C 2: aq. CsCO3 / acetone / 3 h / 20 °C View Scheme

aniline (62-53-3) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-Benzyloxycarbonyl-L-asparaginsaeure-β-anilid (30750-71-1) + Cbz-Asp-anilide

Conditions	Yield
With acetic acid In benzene for 0.166667h; Heating; Yields of byproduct given;	A n/a B 58%
In dimethyl sulfoxide for 0.333333h; Ambient temperature; Yield given. Yields of byproduct given;

4-aminomethyl-benzoic acid ; hydrochloride (67688-72-6) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-4-((3-(benzyloxycarbonylamino)-2,5-dioxopyrrolidin-1-yl)methyl)benzoic acid (953435-25-1)

Conditions	Yield
Stage #1: 4-aminomethyl-benzoic acid ; hydrochloride; N-benzyloxycarbonyl-L-aspartic acid anhydride With pyridine; triethylamine at 20℃; for 9h; Stage #2: With acetic acid at 83℃; for 24h;	56%

methanol (67-56-1) + phenylmagnesium chloride (100-59-4) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → dimethyl (2S)-2-[(phenylmethoxy)carbonylamino]-butane-1,4-dioate (35909-93-4) + (3S)-methyl 3-(benzyloxycarbonylamino)-4-oxo-4-phenylbutanoate

Conditions	Yield
Stage #1: phenylmagnesium chloride; N-benzyloxycarbonyl-L-aspartic acid anhydride In tetrahydrofuran at -78℃; for 4h; Stage #2: With citric acid In tetrahydrofuran at -78 - 20℃; Stage #3: methanol With thionyl chloride	A n/a B 54%

methanol (67-56-1) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-2-benzyloxycarbonylamino-succinic acid 1-methyl ester (4668-42-2)

Conditions	Yield
Stage #1: methanol; N-benzyloxycarbonyl-L-aspartic acid anhydride In ethyl acetate at 20℃; for 5h; Stage #2: With N-cyclohexyl-cyclohexanamine In di-isopropyl ether Stage #3: With hydrogenchloride In water; ethyl acetate pH=2;	54%

N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-benzyloxycarbonyl-L-aspartic acid thioanhydride (1000278-32-9)

Conditions	Yield
With sodium sulfide; tetrabutylammomium bromide In dichloromethane; water for 3h;	47%
With sodium sulfide; tetrabutylammomium bromide In dichloromethane; water for 3h;	47%

1-(2-aminoethyl)-3-(benzyloxy)-2-methylpyridin-4(1H)-one hydrochloride salt + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-4-((2-(3-(benzyloxy)-2-methyl-4-oxopyridin-1(4H)-yl)ethyl)amino)-2-(((benzyloxy)carbonyl)amino)-4-oxobutanoic acid

Conditions	Yield
Stage #1: 1-(2-aminoethyl)-3-(benzyloxy)-2-methylpyridin-4(1H)-one hydrochloride salt With potassium hydroxide In methanol for 1h; Inert atmosphere; Stage #2: N-benzyloxycarbonyl-L-aspartic acid anhydride In N,N-dimethyl-formamide at 59.84℃; for 3h; Inert atmosphere;	44%

methanol (67-56-1) + n-butyl magnesium bromide (693-03-8) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → (S)-3-Benzyloxycarbonylamino-4-oxo-octanoic acid methyl ester + dimethyl (2S)-2-[(phenylmethoxy)carbonylamino]-butane-1,4-dioate (35909-93-4)

Conditions	Yield
Stage #1: n-butyl magnesium bromide; N-benzyloxycarbonyl-L-aspartic acid anhydride In tetrahydrofuran at -78℃; for 4h; Stage #2: With citric acid In tetrahydrofuran at -78 - 20℃; Stage #3: methanol With thionyl chloride	A 41% B n/a

N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) + 1-(3-aminopropyl)-3-(benzyloxy)-2-methylpyridin-4(1H)-one hydrochloride salt → (S)-4-((3-(3-(benzyloxy)-2-methyl-4-oxopyridin-1(4H)-yl)propyl)amino)-2-(((benzyloxy)carbonyl)amino)-4-oxobutanoic acid

Conditions	Yield
Stage #1: 1-(3-aminopropyl)-3-(benzyloxy)-2-methylpyridin-4(1H)-one hydrochloride salt With potassium hydroxide In methanol for 1h; Inert atmosphere; Stage #2: N-benzyloxycarbonyl-L-aspartic acid anhydride In N,N-dimethyl-formamide at 59.84℃; for 3h; Inert atmosphere;	22%

(S)-serine methyl ester (2788-84-3) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-(N-benzyloxycarbonyl-L-α-aspartyl)-L-serine methyl ester

Conditions	Yield
With chloroform

L-Valine methyl ester (4070-48-8) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-(N-benzyloxycarbonyl-L-α-aspartyl)-L-valine methyl ester (159879-61-5)

Conditions	Yield
With ethyl acetate
With potassium hydrogencarbonate; ethyl acetate

L-Valine methyl ester (4070-48-8) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-(N-benzyloxycarbonyl-L-α-aspartyl)-L-valine methyl ester (159879-61-5) + N-(N-benzyloxycarbonyl-L-β-aspartyl)-L-valine methyl ester (159879-62-6)

Conditions	Yield
With potassium hydrogencarbonate; ethyl acetate
With ethyl acetate

L-glutamic acid diethyl ester (16450-41-2) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → N-(N-benzyloxycarbonyl-L-β-aspartyl)-L-glutamic acid diethyl ester + N-(N-benzyloxycarbonyl-L-α-aspartyl)-L-glutamic acid diethyl ester (112842-55-4)

Conditions	Yield
With ethyl acetate

4-methyl pentanamine (5344-20-7) + N-benzyloxycarbonyl-L-aspartic acid anhydride (4515-23-5) → L-aspartic acid isohexyl imide (121790-47-4)

Conditions	Yield
at 130℃; Hydrieren des Reaktionsprodukts an Palladium/Kohle in Essigsaeure enthaltendem Aethanol;

Upstream product

• 1152-61-0 N-Cbz-L-Asp 
• 501-53-1 benzyl chloroformate 
• 100-51-6 benzyl alcohol 

Downstream Products

• 159879-61-5 N-(N-benzyloxycarbonyl-L-α-aspartyl)-L-valine methyl ester 
• 159879-62-6 N-(N-benzyloxycarbonyl-L-β-aspartyl)-L-valine methyl ester 
• 112842-55-4 N-(N-benzyloxycarbonyl-L-α-aspartyl)-L-glutamic acid diethyl ester 
• 39552-95-9 N-(N-benzyloxycarbonyl-L-α-aspartyl)-glycine ethyl ester 
• 39552-94-8 N-(N-benzyloxycarbonyl-L-β-aspartyl)-glycine ethyl ester 
• 4779-31-1 Z-Asp-OBn 
• 23632-73-7 N-carbobenzoxy-L-aspartic acid amide 
• 4668-43-3 (S)-3-(benzyloxycarbonylamino)-4-ethoxy-4-oxobutanoic acid 
• 4616-95-9 6-O-(N-Carbobenzoxy-α-L-aspartyl)-D-glucose 
• 4668-44-4 N-benzyloxycarbonyl-L-aspartic acid α-p-nitrobenzyl ester 
• 39256-89-8 N-Benzyloxycarbonyl-L-asparaginsaeure-β-aethylester 
• 30750-71-1 N-Benzyloxycarbonyl-L-asparaginsaeure-β-anilid 

Relevant academic research and scientific papers

Synthesis and anticonvulsant evaluation of (R)-and (S)-3-carbobenzyloxy- amino-1-oxysuccinimides

A series of (R)-and (S)-3-carbobenzyloxy-amino-1-oxysuccinimides (5a-d) [(S)-3-carbobenzyloxy-amino-1-benzoyloxysuccinimde, (R)-3-carbobenzyloxy-amino- 1-acetyloxysuccinimde, (R)-3-carbobenzyloxy-amino-1,4-nitrobenzoyloxysuccinimde, (R)-3-carbobenzyloxyamino-1,4-fluorobenzoyloxysuccinimde] were synthesized and investigated their anticonvulsant activities in maximal electric shock seizure test and pentylenetetrazole induced seizure test.

A PREPARATION METHOD OF SITAGLIPTIN

The present invention relates to a preparation method of sitagliptin, and more particularly, to a method of preparing sitagliptin using L-aspartic acid having a (R)-beta amino acid structure by mild amide formation, by the use of industrially applicable halo isopropylmagnesium, and by removal of amine protecting group using Pd/C and H2 and carbonyl reduction using reducing agent.

One-pot syntheses of dissymmetric diamides based on the chemistry of cyclic monothioanhydrides. Scope and limitations and application to the synthesis of glycodipeptides

(Chemical Equation Presented) Opening cyclic monothioanhydrides by amines provides a convenient entry into amido thioacids that can be trapped in situ by 2,4-dinitrobenzenesulfonamides, by electron-deficient azides, or by amines in the presence of Sanger's reagent leading, in each case, to dissymmetric diamides in what can be considered a one-pot, three-component coupling sequence. The use of monothiomaleic anhydride and bifunctional nucleophiles such as amino thiols provides access to heterocyclic amides. The low reactivity of cyclic monothioanhydrides toward alcohols enables the use of methanol as solvent and obviates the need for the protection of alcohols in the various reaction components. Reaction of N-benzyloxycarbonyl-L-aspartic monothioanhydride with unprotected glycosyl amines, followed by capture of the thioacid intermediate with N-sulfonyl amino acid derivatives results in a three-component convergent synthesis of glycosylated peptides.

On the racemisation of aspartic anhydride during its preparation

Due to the possible differentiation of both carboxyl groups, N-protected aspartic anhydride is a useful starting material in synthesis. However, most methods published in the literature for its formation lead to partial racemisation, which is generally not mentioned. Herein we report a comparison between the main methods published, with accurate measurements of the enantiomeric purity of this compound.

Cyclic thioanhydrides: Linchpins for multicomponent coupling reactions based on the reaction of thioacids with electron-deficient sulfonamides and azides

(Chemical Equation Presented) Reaction of cyclic thioanhydrides with amines affords amides functionalized with thioacids, which can be trapped in situ with electrondeficient azides or, preferably, 2,4-dinitrobenzenesulfonamides. In this manner the cyclic thioanhydride serves as a linchpin in a three-component coupling sequence. The use of thiomaleic anhydride and a afunctional nucleophile extends the process to heterocycle synthesis, while a cyclic thioanhydride prepared from aspartic acid directly provides N-functionalized asparagine derivatives.

β-Pseudopeptide foldamers. the homo-oligomers of (4R)-(2-oxo-1,3-oxazolidin-4-yl)-acetic acid (D-Oxac)

A total synthesis in solution and a conformational analysis of the homo-oligomers of (4R)-(2-oxo-1,3-oxazolidin-4-yl)-acetic acid (D-Oxac) to the tetramer level are described. As the D-Oxac building block contains both an oxazolidin-2-one and a β-amino acid group, it may represent a new type of conformationally constrained tool for the construction of β-pseudopeptide foldamers. A conformational investigation using NMR and an extensive, unconstrained analysis with a Monte Carlo search to the octamer level, both in water and in chloroform, showed that these homo-oligomers tend to fold in a regular helical structure in a competitive solvent, such as water. Since aqueous solutions are of major relevance for biological systems, these molecules are good candidates for application to these environments.

A new entry to polyfunctionalized 4,5-trans disubstituted oxazolidin-2-ones from L-aspartic acid

A straightforward synthesis of enantiomerically pure (4R,5S)-5-oxazolidinecarboxylic acid, 2-oxo-4-[(t-butyldimethyl-silyloxy)methyl]-, benzyl ester and of (4S,5S)-4-oxazolidinecarboxylic acid, 2-oxo-5-[(t-butyldimethylsilyloxy)methyl]-, benzyl ester was envisaged starting from readily available L-aspartic acid. The key step is the diastereoselective addition of iodine with the introduction of a new stereogenic centre.

Introduction of 4(S)-oxazolidineacetic acid, 2-oxo (D-Oxac) motif in a polypeptide chain: Synthesis and conformational analysis

A four step synthesis of 4(S)-oxazolidineacetic acid, 2-oxo benzyl ester (D-Oxac-OBn) from L-Asp-OH in 45% overall yield is reported. The formation of by-products is completely avoided, by microwave irradiation and by the use of caesium carbonate as base. Moreover the synthesis and IR and 1H NMR conformational analysis of the tetramers Boc-L-Val-D-Oxac-L-Ala-OBn and Boc-L-Val-D-Oxac-Aib-L-Ala-OBn in solution is reported.

Process for producing 1H-3-aminopyrrolidine and derivatives thereof

A process for producing 1H-3-aminopyrrolidine and derivatives thereof is disclosed. The process is especially useful for producing optically active 1H-3-aminopyrrolidine and derivatives thereof and in this case comprises reacting an optically active amino-protected aspartic anhydride represented by the formula (1) with a primary amine represented by the formula R'NH2, subjecting the reaction product to cyclodehydration to obtain an optically active 1-aralkyl-3-(protected amino)pyrrolidine-2,5-dione compound represented by the formula (2), subsequently eliminating the protective group from the 3-position amino group of the compound represented by the formula (2) to obtain an optically active 1-aralkyl-3-aminopyrrolidine-2,5-dione compound represented by the formula (3), reducing the carbonyl groups of the compound represented by the formula (3) to obtain either an optically active 1-aralkyl-3-aminopyrrolidine compound represented by the formula (4) or a salt thereof with a protonic acid, and then subjecting the compound represented by the formula (4) or the salt thereof to hydrogenolysis to obtain an optically active 1H-3-aminopyrrolidine or a protonic acid salt thereof.

Bleach activators

A bleach composition comprises a peroxygen bleach source (for instance hydrogen peroxide, a perborate or a percarbonate salt) and an activator of the formula I: STR1 in which X is O or S; one of E and G is --A-- and the other is --N(R2)--; A is --O-- or --S--; R1 is a C1-50 alkylene group (including cyclo alkylene), optionally interrupted by an arylene group and/or by one or more ether, ester, anhydride, thioether, secondary or tertiary amine, amide or imide linkage, an arylene group or an alkarylene group; R2, is selected from H, alkyl, aralkyl, alkaryl and aryl; R3 is alkyl, aralkyl, alkaryl or aryl, or, when E is --N(R2)--, H; in which R2 and R3 can be joined so as to form a heterocyclic ring with the atoms to which they are attached, and/or in which R1 can be joined with R2 or R3 ; and L is a leaving group which may optionally be joined to any of R1, R2 and R3. The activator gives the composition good bleaching at low temperatures, minimal dye and fabric damage and which bleach a wide range of oxidisable stains.