- Convenient syntheses of δ-aminolevulinic acid
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Two convenient procedures for the synthesis of δ-aminolevulinic acid (5-ALA) are described.
- Nudelman, Ayelet,Nudelman, Abraham
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Read Online
- Synthesis of the natural herbicide δ-aminolevulinic acid from cellulose-derived 5-(chloromethyl)furfural
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Cellulose-derived 5-(chloromethyl)furfural is converted into δ-aminolevulinic acid in three chemical steps involving conversion to 5-(azidomethyl)furfural, photooxidation, and catalytic hydrogenation in 68% overall yield. δ-Aminolevulinic acid is a natural product with important agrochemical and pharmaceutical applications.
- Mascal, Mark,Dutta, Saikat
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Read Online
- A convenient method for introducing oxo group into the β-position of cyclic amines and its application to synthesis of δ-aminolevulinic acid
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Oxo group could be introduced into the β-position of N-methoxycarbonylated cyclic amines by utilizing electrochemical oxidation and/or m-chloroperbenzoic acid oxidation, and this method was applied to the preparation of δ-aminolevulinic acid, an intermediate of chlorophyll biosynthesis.
- Matsumura,Takeshima,Okita
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Read Online
- Synthesis method of 5-aminolevulinic acid hydrochloride
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The invention relates to a synthesis method of 5-aminolevulinic acid hydrochloride, which specifically comprises the following steps: by taking ethyl 4-bromo-4-valerate as a raw material, carrying out amination reaction and hydrolysis reaction to synthesize a target product. The synthesis method disclosed by the invention is mild in reaction condition and high in atom utilization rate, the total yield is 47%, and the process route does not use a heavy metal reagent which is relatively high in toxicity and high in price, is high in safety and conforms to the green chemistry concept.
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Paragraph 0017; 0038; 0040-0041; 0043-0044; 0046-0047; ...
(2022/04/03)
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- Preparation method 5 - ALA intermediate 5 - bromoolevulinic acid ester
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The invention relates to a preparation method of 5 - ALA intermediate 5 - bromoacetyl ester, which is characterized by comprising the following steps: (S1) reaction of the urotropine and a bromine source to prepare the urotropine bromine complex. (S2) Lourotropine bromide complex and levulinic acid ester reaction. Gave 5 - bromoolevulinic acid ester. Compared with the prior art, a bromo reagent such as liquid bromine and 5 - is used directly, NBS-site bromination product yield is increased 5 - 10% or more. The defect that 3 -position bromination or multi-site bromination product is large and separation is difficult in the bromination reaction is overcome. The method is cheap and easily available in raw materials, simple and convenient to operate and suitable for large-scale preparation 5 - ALA intermediate 5 - bromolevulinic acid ester .
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Paragraph 0034; 0053; 0057
(2021/09/22)
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- Preparation method of 5-aminolevulinic acid hydrochloride
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The invention discloses a preparation method of 5-aminolevulinic acid hydrochloride, which comprises the following steps: by taking 1, 3-dichloroacetone as an initial raw material, reacting with Meldrum's acid or a derivative thereof, then carrying out ester exchange, ammoniation reaction and hydrolysis decarboxylation, and finally decolorizing, concentrating and recrystallizing to obtain the 5-aminolevulinic acid hydrochloride. The method is high in yield, convenient to operate, stable in quality and suitable for industrial production.
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Paragraph 0038; 0061; 0068-0069
(2021/11/03)
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- Preparation method of 5-aminolevulinic acid hydrochloride
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The invention discloses a preparation method of 5-aminolevulinic acid hydrochloride, the method comprises the following steps: taking 1, 3-dichloroacetone as an initial raw material, reacting with a malonate compound, then carrying out ammonification reaction and hydrolysis decarboxylation, and finally decolorizing, concentrating and recrystallizing to obtain the 5-aminolevulinic acid hydrochloride. The method is high in yield, convenient to operate, stable in quality and suitable for large-scale industrial production.
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Paragraph 0043; 0049-0050
(2021/11/06)
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- Preparation method of 5 -aminolevulinic acid hydrochloride intermediate (by machine translation)
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The invention relates to a preparation method of 5 -aminolevulinic acid hydrochloride intermediate, which belongs to the field of pharmaceutical compound synthesis and provides a 5 -aminolevulinic acid hydrochloride intermediate preparation method which comprises the following technical points: (a), (1) or (2) compound in reaction solvent a, oxidizing agent a, compound of formula (5); or process b) wherein the compound of formula (6) or formula (3 4) is obtained under the action of a reaction solvent b and an oxidizing agent b 6. The compound of formula (6) is then purified to give 5 -aminolevulinic acid hydrochloride by an acidic hydrolysis deprotecting group, or a direct acidic hydrolysis deprotecting group. The environment-friendly oxidation reagent is adopted, the quality requirement of high-quality medicine raw materials can be met at the same time, the production efficiency can be improved, and the requirement of industrial large-scale production can be met. (by machine translation)
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Paragraph 0060; 0062-0063; 0065-0066; 0068-0069; 0071-0072
(2020/09/08)
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- Method for manufacturing methyl 5-bromolevulinate and manufacturing method 5-aminolevulinic acid heyl ester hydrochloride using the same
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The present invention relates to a method of preparing methyl 5-bromolevulinate, capable of improving the yield of a final product while having stability of a product, and a method of preparing 5-aminoalkylenic acid hexyl ester hydrochloride using the same. To this end, the method of preparing methyl 5-bromolevulinate comprises: a first reaction step of mixing levulinic acid, methanol and bromine in a container and making the mixture react; a second reaction step of mixing a first product of the first reaction step, a first reactant not reacting in the first reaction step, ultrapure water and chloroform solution, and making the mixture react; an extraction step of extracting a chloroform solution layer from a first mixture formed after the second reaction step; a third reaction step of mixing the chloroform solution layer extracted in the extraction step, ethyl ether, and sodium bicarbonate saturated aqueous solution and stirring the mixture; a purification step of separating an aqueous solution layer from a second mixture formed after the third reaction step; a fourth reaction step of mixing a remaining mixture after the aqueous solution layer is separated from the second mixture with N-Hexane, and making the mixture react; a precipitation step of precipitating methyl 5-bromolevulinate in a solid state from a third mixture while quenching the third mixture formed after the fourth reaction step; and a filtering step of filtering the methyl 5-bromolevulinate in the solid state from a fourth mixture formed after the precipitation step by using a filtration device.COPYRIGHT KIPO 2019
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Paragraph 0052
(2019/02/28)
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- Synthesis of 5-aminolevulinic acid with nontoxic regents and renewable methyl levulinate
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Synthesis of 5-aminolevulinic acid (5-ALA) was presented with novel bromination of biobased methyl levulinate (ML), followed by ammoniation and hydrolysis. Copper bromide (CuBr2) was employed as the bromination reagent with higher selectivity and activity instead of the conventional liquid bromine (Br2). 5-ALA was obtained in a high yield (64%) and purity (>95%) by optimum design, which is of great potential in industrialization.
- Zai, Yuxia,Feng, Yunchao,Zeng, Xianhai,Tang, Xing,Sun, Yong,Lin, Lu
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p. 10091 - 10093
(2019/04/10)
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- Transition Metal-Free Reduction of Activated Alkenes Using a Living Microorganism
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Microorganisms can be programmed to perform chemical synthesis via metabolic engineering. However, despite an increasing interest in the use of de novo metabolic pathways and designer whole-cells for small molecule synthesis, the inherent synthetic capabilities of native microorganisms remain underexplored. Herein, we report the use of unmodified E. coli BL21(DE3) cells for the reduction of keto-acrylic compounds and apply this whole-cell biotransformation to the synthesis of aminolevulinic acid from a lignin-derived feedstock. The reduction reaction is rapid, chemo-, and enantioselective, occurs under mild conditions (37 °C, aqueous media), and requires no toxic transition metals or external reductants. This study demonstrates the remarkable promiscuity of central metabolism in bacterial cells and how these processes can be leveraged for synthetic chemistry without the need for genetic manipulation.
- Brewster, Richard C.,Suitor, Jack T.,Bennett, Adam W.,Wallace, Stephen
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supporting information
p. 12409 - 12414
(2019/08/16)
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- A 5 - aminolevulinic acid hydrochloride of new synthetic method (by machine translation)
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The invention belongs to the field of organic synthesis, in particular relates to a 5 - aminolevulinic acid hydrochloride new synthesis method. The synthesis method the new synthesis method ech as the starting material, by Gabriel reaction, ring-opening, oxidation, substituted, hydrolysis reaction steps such as to obtain the target product 5 - aminolevulinic acid hydrochloride. The invention uses a 5 - aminolevulinic acid hydrochloride new synthesis method, can significantly speed up the reaction rate and to improve the yield, while at the same time little side reaction, the operation is simple, after treatment is convenient, and is suitable for industrial production. (by machine translation)
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Paragraph 0009-0010
(2019/05/16)
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- Method for synthesizing 5-aminolevulinic acid hydrochloride
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The invention discloses a method for synthesizing 5-aminolevulinic acid hydrochloride. The method is characterized by comprising the following steps: (1) taking a compound A as a raw material, carrying out alkali deprotonation and reacting with succinic anhydride to generate a compound B as shown in specification; and (2) hydrolyzing the compound B under acidic conditions to obtain a target compound as shown in specification, wherein R1 is phenyl or substituted phenyl; R2 is phenyl, substituted phenyl, alkyl or H; and R3 is alkyl, benzyl or substituted benzyl. The synthesis route is simple, only two steps are needed, the synthesis period is short, and the production cost is reduced. According to the method, classical reaction is adopted, the reaction condition is mild, the method is easy to operate, industrial production is facilitated, and the production safety is improved. Reaction raw materials are easily available.
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Paragraph 0060-0062; 0064-0065; 0066; 0068
(2019/06/27)
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- Method for preparing 5-aminolevulinate
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The invention discloses a method for preparing 5-aminolevulinate. The method comprises the following step: subjecting a substance A to acidolysis with an acidification reagent, thereby obtaining the 5-aminolevulinate. According to the method, various raw materials are cheap and readily available, the consumption of raw materials with relatively high toxicity and serious pollution is avoided, the process route is simple, the reaction conditions are mild, and the energy consumption is lowered, so that the method is applicable to industrial production; the added value of the product is high, andthus, the product has a potential industrial application prospect.
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Paragraph 0061-0063; 0076; 0077
(2019/04/04)
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- Synthesis method of 5-aminolevulinic acid hydrochloride
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The invention relates to a synthesis method of 5-aminolevulinic acid hydrochloride. The method includes the steps that succinic anhydride is used as the raw material and subjected to monoesterification with methanol to obtain monomethyl succinate; monomethyl succinate and N,N-carbonyldiimidazole are subjected to a nucleophilic substitution reaction to obtain methyl 4-(1-imidazole)-4-oxobutanoate;methyl 4-(1-imidazole)-4-oxobutanoate and nitromethane are subjected to a nucleophilic substitution reaction under the catalysis of an alkali compound to obtain methyl 5-nitro-4-oxopentanoate; methyl5-nitro-4-oxopentanoate and a metallic reducing agent are subjected to a reduction reaction, and through hydrolysis, 5-aminolevulinic acid hydrochloride is obtained. The process is simple, the raw material is easy to obtain, no special rectification and recrystallization devices are needed for treating intermediate products, no toxic and expensive raw materials are used, the use of heavy metal reducing agents is avoided to prevent environmental pollution, the synthesis cost is low, the purity of the synthetic product can reach 97% in recrystallization detection, and the total yield is high andreaches 70% or above.
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Paragraph 0023; 0026; 0027; 0030; 0031; 0034; 0035; 0038
(2019/02/10)
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- Synthesis method of 5-aminolevulinic acid hydrochloride
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The invention relates to a synthesis method of 5-aminolevulinic acid hydrochloride (5-ALA), furfuryl amine (2-furylamine) is used as an initial raw material, and the target product is synthesized through four steps of amino protection, oxidation reaction, reduction reaction and hydrolysis decarboxylation. Reagents used in the synthesis method are low in price, easy to obtain, and environment-friendly and the operation is simple.
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Paragraph 0039; 0043; 0063; 0067
(2019/04/26)
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- Novel method for preparing hydrochloric aminolevulinic acid
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The invention discloses a novel method for preparing hydrochloric aminolevulinic acid (5-ALA), and belongs to the field of chemical synthesis. According to the method, with a glycine derivative as a starting material, a brand-new 5-ALA synthesizing route is provided through four-step reaction of condensation, substitution, deprotection and hydrolysis. By the synthesis method, the route is short, operation is simple and the yield is high; the synthesis method is suitable for large-scale industrial production.
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Paragraph 0037-0038; 0045-0048; 0055-0058; 0065-0068; 0075
(2018/09/13)
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- Preparation methods for 5-aminolevulinic acid hydrochloride and 5-aminolevulinic acid hydrochloride intermediate
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The invention discloses preparation methods for a 5-aminolevulinic acid hydrochloride and a 5-aminolevulinic acid hydrochloride intermediate. The preparation method for the 5-aminolevulinic acid hydrochloride intermediate comprises: (1) carrying out a reaction on a compound 2 and isopropylidene malonate in an organic solvent under the actions of an organic alkali and a condensing agent to obtain acompound 3; and (2) carrying out a reaction on the compound 3 in a C1-C4 alcohol solvent to obtain a compound 4, wherein R1 and R' are respectively and independently C1-C4 alkyl. The present invention further provides a method for preparing a 5-aminolevulinic acid hydrochloride by using the 5-aminolevulinic acid hydrochloride intermediate. According to the present invention, the intermediate product is basically solid and is easily crystallized and purified; and the method has characteristics of high yield, low production cost and easy operation, and is suitable for industrial production. Thecompounds 1, 2, 3 and 4 are defined in the specification.
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Paragraph 0075; 0076; 0081
(2018/09/11)
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- Preparation method of 5-aminolevulinic acid hydrochloride
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The invention relates to a preparation method of 5-aminolevulinic acid hydrochloride, belonging to the technical field of drug intermediate synthesis. In order to solve the problems of long route and great pollution at present, the invention provides the preparation method of the 5-aminolevulinic acid hydrochloride. The preparation method is characterized in that the method comprise the following steps of under the existence of organic alkali and DMAP, enabling benzoyl glycine to react with butanedioic anhydride by using Dakin-West to obtain benzoyl aminolevulinic acid; under the existence of hydrochloric acid, enabling the benzoyl aminolevulinic acid to be subjected to hydrolysis reaction to obtain the 5-aminolevulinic acid hydrochloride. The synthetic method has the advantages that the reaction route is short, the raw materials are convenient to obtain, the cost is low, the reaction operation is simple and convenient and the pollution is less, and the method has the effects of high product yield and high purity.
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Paragraph 0028; 0034-0036
(2018/01/14)
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- A process for preparing amino levulinic acid
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The invention relates to a new preparation process of 5-aminolevulinic acid (5-ALA) hydrochloride. The 5-ALA is a second-generation photosensitizer, and has a structure shown in the specification. The 5-ALA hydrochloride has been used for treating photosensitive keratosis in America. The 5-ALA hydrochloride is used for treating dermatological condyloma acuminatum in China. Indications related to the 5-ALA are also extended in clinical application. According to the new preparation process, 4-alkenylbenzyl valerate is used as a starting raw material and is subjected to oxidation, addition, oxidation and catalytic hydrogenation to successfully synthesize the 5-ALA.
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Paragraph 0039; 0051; 0052
(2018/07/10)
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- A COMPOSITION FOR SKIN REGENERATION FOR APPLICATION TO THE SKIN
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The present invention refers to 5 - aminolevulinic acid cyclohexyl ester hydrochloride of manufacturing method relates to search, 5 - aminolevulinic acid hydrochloride (5-aminolevulinic acid hydrochloride) to prepare for the steps requiring; and said 5 - aminolevulinic acid hydrochloride, ethylhexyl alcohol (hexyl alcohol) and thionil chloride (thionyl chloride) reaction step reacting a mixing; includes. According to the present invention, and, by optimising the synthesis process step 2, excellent a failed normal high yield in high purity unit is off. (by machine translation)
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Paragraph 0083-0085
(2017/05/25)
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- Preparation method of 5-aminolevulinic acid and Use of the same
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The present invention refers to 5-aminolevulinic acid or 5-aminolevulinic acid novel manufacturing method and 5-aminolevulinic acid or a pharmaceutically acceptable salts, for the treatment of skin diseases relates to the use. Synthesis of 5-aminolevulinic acid salt the present invention according to 5-aminolevulinic acid or features a previously known method being much high yield than synthetic method, heavy metals nor chlorine, boron intermediates halogen such as single plate, do not is not synchronized residual product, organic solvent as a solvent in addition a solvent soluble instead, more wound on a clean roll and a.. And the present invention according to 5-aminolevulinic acid or a pharmaceutically acceptable salt by comprising, as an active ingredient for treatment or treatment skin disease gel system or the like, and number lotion composition is topically applied to the skin disease site more excellent the active mode, and for conserving having electrode and the ground of the diode, skin diseases in particular psoriasis alarm healing therapeutic agent for a disease is constructed based on the character data useful for the development can be used..
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Paragraph 0064-0067
(2016/12/12)
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- LIGNIN OXIDATION AND PRODUCTS THEREOF
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Provided herein is a method of oxidizing lignin. Further disclosed herein are aromatic and non-aromatic compounds obtained from oxidized lignin.
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Page/Page column 80
(2012/06/16)
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- PROCESS FOR PRODUCING 5-AMINOLEVULINIC ACID HYDROCHLORIDE
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A process for producing 5-aminolevulinic acid hydrochloride crystals which comprises: adsorbing the 5-aminolevulinic acid contained in a crude 5-aminolevulinic acid solution onto a cation-exchange resin; subsequently desorbing the acid with an aqueous solution containing ammonium ions while utilizing a change in the electrical conductivity or pH of the solution resulting from the desorption as an index to recovery to thereby obtain an aqueous solution of high-purity 5-aminolevulinic acid; adding chloride ions to the aqueous solution; and mixing an organic solvent therewith.
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Page/Page column 13
(2008/06/13)
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- BENZOXAZEPINE COMPOUND
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A compound represented by the formula [1]: wherein ring A and ring B each represent an optionally substituted benzene ring; ring C represents an optionally further substituted aromatic ring; R1 represents a lower alkyl group optionally substituted with an optionally substituted hydroxyl group; X1a represents a bond or optionally substituted lower alkylene; X1b represents a bond or optionally substituted lower alkylene; X2 represents a bond, -O- or -S-; X3 represents a bond or an optionally substituted divalent hydrocarbon group; Y represents an optionally esterified or amidated carboxyl group, or a salt thereof. The compound of the formula [I] is safer and has more potent lipid lowering activity such as squalene synthase inhibitory activity (cholesterol lowering activity) and triglyceride lowering activity, and thus it is a compound useful as an agent for preventing or treating hyperlipemia.
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Page/Page column 27
(2010/11/08)
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- 5-azido-laevulinic acid, method for the production thereof and its use
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The present invention relates to 5-azido levulinic acid, a process for its preparation, its use. Using 5-azido levulinic acid as starting material for the synthesis of 5-amino levulinic acid hydrochloride it is possible to obtain the latter in good yield an in pharmaceutical acceptable quality. 5-Azido levuliniv acid is synthesized in that methyl 5-bromo levulinate and/or methyl 5-chloro levulinate is converted with aqueous hydrochloric acid and as a result of an incomplete bromine/chlorine exchange at the C-5-postion a mixture of 5-chloro levulinic acid and 5-bromo levulinic acid is obtained, and the obtained 5-chloro levulinic acid, a mixture of 5-chloro levulinic acid and 5-bromo levulinic acid and the pure 5-bromo levulinic acid is transferred into 5-azido levulinic acid by conversion with a nucleophilic azide.
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- Preparation of [1,2,3,4,5-13C 5]-5-Amino-4-oxopentanoic Acid (ALA) - Design of a Synthetic Scheme to Prepare Any 13C- and 15N-Isotopomer with High Isotopic Enrichment
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5-Amino-4-oxopentanoic acid (5-aminolevulinic acid) is a precursor in the biosynthesis of the biologically active porphyrins such as chlorophyll, bacteriochlorophyll, heme, etc. These systems are central in photosynthesis, oxygen transport, electron transport, etc. In this paper we describe a simple scheme to prepare any isotopomer of 5-aminolevulinic acid in a few steps in high yield. Using a similar scheme, levulinic acid can now also be prepared in any isotopomeric form. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
- Shrestha-Dawadi, Prativa Bade,Lugtenburg, Johan
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p. 4654 - 4663
(2007/10/03)
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- The synthesis and applications of 5-aminolevulinic acid (ALA) derivatives in photodynamic therapy and photodiagnosis
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A route has been developed to high-purity precursors, viz., ALA esters, to be used in photodiagnosis and photodynamic therapy. Hexyl, butyl and methyl 5-aminolevulinates are similar to the ALA acid in chemical stability and efficacy in producing the appropriate photosensitizer PpIX. Tests carried out on animal models showed the method based on the esters to be the more selective.
- Dabrowski, Zbigniew,Kwasny, Miroslaw,Kaminski, Jaroslaw,Beldowicz, Maria,Lewicka, Lidia,Obukowicz, Bozena,Kaliszewski, Miron,Pirozynska, Ewa
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p. 219 - 224
(2007/10/03)
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- Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters
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A process of preparing an acid addition salt of delta-aminolevulinic acid comprising: dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures thereof to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing said alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.
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- Synthesis of analogues of 5-aminolaevulinic acid and inhibition of 5-aminolaevulinic acid dehydratase
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Syntheses are described of several analogues of 5-aminolaevulinic acid (ALA), which are potential inhibitors of ALA dehydratase (porphobilinogen synthase), an early enzyme of tetrapyrrole biosynthesis.Most of the analogues are relatively weak competitive inhibitors of the enzyme from Bacillus subtilis or irreversible inhibitors due to multiple alkylation of the enzyme but the 3-oxa and 3-thia analogues are potent mechanism-based inhibitors which inactive, by acylation of a nucleophilic residue, probably the active-site lysine residue.The kinetics of the inactivation by 3-thiaALA have implications for the mechanism of the enzymic reaction.
- Appleton, Diana,Duguid, A. Bruce,Lee, Sung-Koo,Ha, Young-Jin,Ha, Hyun-Joon,Leeper, Finian J.
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- Process for preparing 5-aminolevulinic acid
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A process for preparing 5-aminolevulinic acid or a salt thereof, which comprises reacting furfurylamine, of which the amino group has been protected, with oxygen molecule under irradiation by light in the presence of a sensitizer; hydrogenating the resulting compound in the presence of a metallic catalyst; and hydrolyzing the hydrogenated compound. 5-Aminolevulinic acid, useful as a raw material for various chemicals and as an agricultural chemical, can be prepared at a high yield by a simple procedure from a raw material which is inexpensive and readily available.
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- Syntheses of γ-oxo acids or γ-oxo esters by photooxygenation of furanic compounds and reduction under ultrasound: Application to the synthesis of 5-aminolevulinic acid hydrochloride
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The photooxygenation of 5-hydroxymethyl-2-furfural (1a) or derivatives 1b-g yields 4-hydroxy-Δ2-butenolides 2 which are the percursors of butenolides 3 or α,β-unsaturated γ-oxo esters 5. The selective reduction of olides 2 or oxo esters 5 with zinc in acetic acid under sonication leads to γ-oxo acids 4 or γ-oxo esters 6. The photooxygenation of amino derivative 1d, followed by selective reduction of corresponding lactone 2d, gives 5-aminolevulinic acid hydrochloride (7) (ALA) after hydrolysis.
- Cottier,Descotes,Eymard,Rapp
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p. 303 - 306
(2007/10/02)
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- Selective bromination of ketones. A convenient synthesis of 5-aminolevulinic acid
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Bromination of unsymmetrical ketones with Br2 in methanol proceeded regioselectively in good yield at the less substituted methyl carbon. The bromination of levulinic acid using this method was followed by azidation and amination to lead to an efficient three-step synthesis of 5-aminolevulinic acid in 36% overall yield.
- Ha,Lee,Ha,Park
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p. 2557 - 2562
(2007/10/02)
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- Method of preparing an acid additional salt of delta-aminolevulinic acid
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An acid addition salt of δ-aminolevulinic acid is prepared in such a way that tetrahydrofurfurylamine (VI) is reacted with phthalic anhydride under an anhydrous condition to introduce a phthal group which protects amino group of tetrahydrofurfurylamine to give N-tetrahydrofurfuryl phthalimide (III), carbon atoms of the first- and fourth-positions of thus obtained N-tetrahydrofurfurylphthalimide (III) are oxidized at 80° C. using sodium periodate as a oxidizing agent and ruthenium chloride hydrate as a catalyst to yield 5-phthalimidolevulinic acid (II), then the protecting group of 5-phthalimidolevulinic acid (II) is deprotected using an acid to prepare an acid additional salt of δ-aminolevulinic acid. The acid additional salt of δ-aminolevulinic acid is readily converted by neutralization by an alkali to δ-aminolevulinic acid, which is very useful as a precursor of Vitamin B12, heme and chlorophyll.
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- Process for the preparation of N-acyl derivatives of 5-aminolevulinic acid, as well as the hydrochloride of the free acid
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The invention relates to a process for the preparation of N-acyl derivatives of 5-aminolevulinic acid of general formula R-CO-NH-CH2 -CO-CH2 -CH2 -COOH, in which R stands for methyl, ethyl, propyl, isopropyl, butyl, phenyl, benzyl, furyl or furfuryl, as well as the hydrochloride of the free acid by acid hydrolysis, characterized in that the 5-hydroxymethyl furfural is condensed with a nitrile in acid solution and the N-acyl-aminomethyl furfural compound obtained is converted by photooxidation into a N-acyl-5-aminomethyl-5-hydroxydihydro-2,5-furan-2-one and the latter is reduced with zinc in acetic acid under ultrasonic treatment to N-acyl-5-aminolevulinic acid and by acid hydrolysis the 5-aminolevulinic hydrochloride is obtained.
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- Synthesis of 5-Aminolevulinic Acid
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A 3-step synthesis of 5-aminolevulinic acid is described. - Key words: 5-Aminolevulinic Acid
- Benedikt, Eva,Koest, Hans-Peter
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p. 1593 - 1594
(2007/10/02)
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- SYNTHESIS OF α-AMINOKETONES VIA SELECTIVE REDUCTION OF ACYL CYANIDES
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Reduction of acyl cyanides with zinc in acetic acid in the presence of excess acetic anhydride leads to N-acetyl-α-aminoketones in good yields.An efficient three-step synthesis of 5-aminolevulinic acid by this method is described.
- Pfaltz, Andreas,Anwar, Saeed
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p. 2977 - 2980
(2007/10/02)
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- A Three-Step Synthesis of δ-Aminolaevulinic Acid
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Piperidine-2,5-dione (4) is prepared by catalytic hydrogenation of 5-hydroxy-2-pyridone (3).Ring opening of the lactam 4 with concentrated hydrochloric acid yields the hydrochloride of δ-aminolaevulinic acid (2).
- Herdeis, Claus,Dimmerling, Anna
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p. 304 - 306
(2007/10/02)
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