86087-23-2Relevant articles and documents
A S - (+) -3 - hydroxy tetrahydrofuran chemical synthesis method
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Paragraph 0023-0025, (2019/04/04)
The invention discloses a S - (+) - 3 - hydroxy tetrahydrofuran chemical synthesis method, includes the following operation steps: 1, compound 1 in the presence of thionyl chloride and methanol reaction to obtain compound 2; 2, in the solvent, compound 2 in the presence of a reducing agent and the reaction to obtain compound 3; 3, compound 3 in the presence of paratoluene sulfonic acid, reaction to obtain compound S - (+) - 3 - hydroxy tetrahydrofuran.
Preparation method of (s)-3-hydroxytetrahydrofuran
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Paragraph 0032; 0037-0039; 0044-0046; 0051-0053; 0058-0060, (2019/11/13)
The invention provides a preparation method of (s)-3-hydroxytetrahydrofuran. According to the preparation method, ethyl 4-chloroacetoacetate is taken as an initial raw material, (s)-4-chloro-3 hydroxyl-1-butanol is prepared, wherein a substrate is dissolved in a first solvent, an alkali is added, under the catalytic effect of a first catalyst and a second catalyst, asymmetric hydrogenation reaction with hydrogen gas is carried out to produce (s)-4-chloro-3 hydroxyl-1-butanol; chiral 3-hydroxytetrahydrofuran is prepared, wherein prepared chiral 4-chloro-3 hydroxyl-1-butanol is dissolved in a second solvent, an acid is added as a catalyst, and reaction is carried out to obtain (s)-3-hydroxytetrahydrofuran; wherein the first catalyst is a complex generated through reaction of [Ir(COD)Cl]2 with phosphine-pyridine ligand, and the second catalyst is Ru-MACHO complex. The reaction route is short; technology is simple; raw materials are cheap and easily available; production cost is low; reaction process environment pollution is low; product optical purity is high; and the preparation method is suitable for industrialized production.
Preparation method of (S)-3-hydroxytetrahydrofuran
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Paragraph 0043, (2018/06/15)
The invention discloses a preparation method of (S)-3-hydroxytetrahydrofuran. The problems that butantriol is difficult to separate in the production process, the yield is not high and the impurity content and the isomer content of the products are high are mainly solved. The preparation method of (S)-3-hydroxytetrahydrofuran comprises the following steps: under the existence of sulfoxide chloride, malic acid reacts with methanol to generate a compound II; under the existence of silver oxide, performing reaction on the compound II and benzyl bromide to generate a compound III; reducing the compound III by sodium borohydride to generate a compound IV; performing dehydration and ring closing on the compound IV by p-toluenesulfonic acid to generate a compound V; and taking palladium carbon asa catalyst and performing hydrogen reduction treatment on the compound V to obtain the product. The method is simple in aftertreatment and environment-friendly; the yield of the products is increasedby 80 percent or more, the purity is more than 99.5 percent and the chiral purity is more than 99.2 percent; and the method is suitable for industrialized production. (The formulas are as shown in the description).
Methodology Development in Directed Evolution: Exploring Options when Applying Triple-Code Saturation Mutagenesis
Qu, Ge,Lonsdale, Richard,Yao, Peiyuan,Li, Guangyue,Liu, Beibei,Reetz, Manfred T.,Sun, Zhoutong
, p. 239 - 246 (2018/02/09)
Directed evolution of stereo- or regioselective enzymes as catalysts in asymmetric transformations is of particular interest in organic synthesis. Upon evolving these biocatalysts, screening is the bottleneck. To beat the numbers problem most effectively, methods and strategies for building “small but smart” mutant libraries have been developed. Herein, we compared two different strategies regarding the application of triple-code saturation mutagenesis (TCSM) at multiresidue sites of the Thermoanaerobacter brockii alcohol dehydrogenase by using distinct reduced amino-acid alphabets. By using the synthetically difficult-to-reduce prochiral ketone tetrahydrofuran-3-one as a substrate, highly R- and S-selective variants were obtained (92–99 % ee) with minimal screening. The origin of stereoselectivity was provided by molecular dynamics analyses, which is discussed in terms of the Bürgi–Dunitz trajectory.
Production technology of 3-hydroxytetrahydrofuran with high optical purity
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Paragraph 0028; 0032; 0037; 0038; 0043, (2017/10/06)
The invention discloses a production technology of3-hydroxytetrahydrofuran with high optical purity. The production technology comprises the following steps: (1) taking chloroacetoacetic acid ethyl ester as a starting raw material, adding appropriate amount of solvents, chiral catalysts and reducing agents, and reacting at an appropriate temperature to obtain chiral ethyl 4-chloro-3-hydroxybutyrate; (2) taking the chiral ethyl 4-chloro-3-hydroxybutyrate obtained in step (1) as a raw material, adding the appropriate amount of solvents and metal borohydride reducing agents, and reacting at the appropriate temperature to obtain chiral 4-chloro-3-hydroxy-1-butanol; (3) taking the chiral 4-chloro-3-hydroxy-1-butanol obtained in step (2) as the raw material, adding appropriate amount of catalysts and solvents, and reacting at the appropriate temperature to obtain chiral 3-hydroxytetrahydrofuran. According to the production technology of the 3-hydroxytetrahydrofuran with the high optical purity, the chiral 3-hydroxytetrahydrofuran can be produced through a three-step reaction, the shortcomings of complicated production operation and high production cost are solved, and products with high optical purity can be produced.
A pharmaceutical intermediates (S)-3 - hydroxy tetrahydrofuran preparation method (by machine translation)
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Paragraph 0043, (2017/08/31)
The invention provides a pharmaceutical intermediate (S)- 3 - hydroxy tetrahydrofuran preparation method. The method other than racemic 1, 2, 4 - butanetriol as raw materials synthesis of racemic 3 - hydroxy tetrahydrofuran, then esterification of racemic tetrahydrofuran-yl - 3 - fatty acid ester. By lipase hydrolysis in the racemic mixture of (R)- tetrahydrofuran-based - 3 - fatty acid ester after, in in the hydrolysis product under the condition of separating, using the mitsunobu reaction will be hydrolyzed to obtain the of (R)- 3 - hydroxy tetrahydrofuran is converted into (S)- tetrahydrofuran-based - 3 - carboxylic acid ester, finally under alkaline condition all of the tetrahydrofuran ester hydrolyzed to obtain the final product (S)- 3 - hydroxy tetrahydrofuran. (by machine translation)
(S)- 3 - hydroxy tetrahydrofuran and (R)- 3 - hydroxy tetrahydrofuran preparation method
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Paragraph 0050; 0051; 0052, (2017/08/02)
The invention discloses a preparation method of (S)-3-hydroxytetrahydrofuran and (R)-3-hydroxytetrahydrofuran, relating to the technical field of preparation of five-element heterocyclic compounds containing one oxygen atom as the only heterocyclic atom. The method comprises the following steps: by using (S)-carnitine or (R)-carnitine as the initial raw material, carrying out reduction reaction in a reducer and an organic solvent to obtain (S) or (R)-2,4-dihydroxy-N,N,N-trimethyl butyl amine alkali; adding a hydrogen chloride organic solvent solution into an organic solvent to perform salification reaction to obtain (S) or (R)-2,4-dihydroxy-N,N,N-trimethyl butyl amine hydrochloride; and finally, adding alkali into a polar solvent, heating, and carrying out cyclization reaction to obtain the (S) or (R)-3-hydroxytetrahydrofuran. The method has the advantages of low cost, simple technique, high yield, cheap and accessible raw materials, short reaction steps, short period and low pollution, and is suitable for industrial production.
Preparation Method for 3-Hydroxytetrahydrofuran
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Paragraph 0021; 0024; 0027; 0028, (2017/08/02)
The present invention relates to a method for preparing 3-hydroxytetrahydrofuran, and more specifically, to a method for preparing 3-hydroxytetrahydrofuran (3) from 4-halo-3-hydroxybutyric acid ester by means of Reaction Formula 1 below, wherein the method comprises the steps of: reacting 4-halo-1,3-butanediol with an inorganic base in C1-C4 alcohol; and then refining 3-hydroxytetrahydrofuran (3) by removing filtering and removing generated salt and performing vacuum distillation thereonto. [Reaction Formula 1] Wherein X=Cl, Br or I, and R=C1-C4 alkyl group or aryl group.
Catalytic Asymmetric Reduction of Difficult-to-Reduce Ketones: Triple-Code Saturation Mutagenesis of an Alcohol Dehydrogenase
Sun, Zhoutong,Lonsdale, Richard,Ilie, Adriana,Li, Guangyue,Zhou, Jiahai,Reetz, Manfred T.
, p. 1598 - 1605 (2016/03/15)
Catalytic asymmetric reduction of prochiral ketones with the formation of enantio-pure secondary alcohols is of fundamental importance in organic chemistry, chiral man-made transition-metal catalysts, or organocatalysts and enzymes of the alcohol dehydrogenase (ADH) type. A distinct limitation is the traditional requirement that the α- and α′-moieties flanking the carbonyl function differ sterically and/or electronically. Difficult-to-reduce ketones such as tetrahydrofuran-3-one and tetrahydrothiofuran-3-one and related substrates are particularly challenging, irrespective of the catalyst type. The ADH from Thermoethanolicus brockii (TbSADH) is an attractive industrial biocatalyst, because of its high thermostability, but it also fails in the reduction of such ketones. We have successfully applied directed evolution using the previously developed concept of triple-code saturation mutagenesis at sites lining the TbSADH binding pocket with tetrahydrofuran-3-one serving as the model compound. Highly (R)- and (S)-selective variants were evolved (95%-99% ee) with minimal screening. These robust catalysts also proved to be effective in the asymmetric reduction of tetrahydrothiofuran-3-one and other challenging prochiral ketones as well. The chiral products, which are generally prepared by multistep routes, serve as synthons in the preparation of several important therapeutic drugs.
Use of 'small but smart' libraries to enhance the enantioselectivity of an esterase from Bacillus stearothermophilus towards tetrahydrofuran-3-yl acetate
Nobili, Alberto,Gall, Markus G.,Pavlidis, Ioannis V.,Thompson, Mark L.,Schmidt, Marlen,Bornscheuer, Uwe T.
, p. 3084 - 3093 (2013/07/26)
Two libraries of simultaneous double mutations in the active site region of an esterase from Bacillus stearothermophilus were constructed to improve the enantioselectivity in the hydrolysis of tetrahydrofuran-3-yl acetate. As screening of large mutant libraries is hampered by the necessity for GC/MS analysis, mutant libraries were designed according to a 'small but smart' concept. The design of focused libraries was based on data derived from a structural alignment of 3317 amino acid sequences of α/β-hydrolase fold enzymes with the bioinformatic tool 3dm. In this way, the number of mutants to be screened was substantially reduced as compared with a standard site-saturation mutagenesis approach. Whereas the wild-type esterase showed only poor enantioselectivity (E = 4.3) in the hydrolysis of (S)-tetrahydrofuran-3-yl acetate, the best variants obtained with this approach showed increased E-values of up to 10.4. Furthermore, some variants with inverted enantiopreference were found. A semi-rational approach was applied for the enhancement of the enantioselectivity of an esterase from Bacillus stearothermophilus towards the industrially interesting substrate tetrahydrofuran-3-yl acetate, based on data derived from structural alignment. The design of 'small but smart' libraries led to a 2.4-fold increase of (S)-selectivity compared to wild type enzyme, while some mutants with marginal (R)-selectivity were found.
