5061-21-2Relevant articles and documents
Preparation method of DL-hydroxy selenomethionine
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Paragraph 0008; 0016-0015, (2021/06/02)
The invention belongs to the field of preparation of organic compounds. The invention provides a preparation method of DL-hydroxy selenomethionine. The method is characterized in that gamma-butyrolactone is used as a raw material, alpha-hydroxyl-gamma-butyrolactone is synthesized through alpha-bromination and hydroxylation, and then the alpha-hydroxyl-gamma-butyrolactone reacts with sodium methyl selenol to obtain the DL-hydroxyl selenomethionine. The method has the advantages of easily available raw materials, mild reaction conditions and low cost, and is suitable for large-scale preparation of DL-hydroxyselenomethionine.
A two-phase bromination process using tetraalkylammonium hydroxide for the practical synthesis of α-bromolactones from lactones
Hosono, Kazumi,Kodama, Shintaro,Nomoto, Akihiro,Ochi, Takanori,Ogawa, Akiya,Tabuchi, Akihiro,Yamamoto, Yuki,Yamazaki, Kento
supporting information, p. 2906 - 2914 (2022/01/12)
A simple and efficient method for α-brominating lactones that affords α-bromolactones under mild conditions using tetraalkylammonium hydroxide (R4N) as a base was developed. Lactones are ring-opened with Br2 and a substoichiometric amount of PBr3, leading to good yields of the corresponding α-bromocarboxylic acids. Subsequent intramolecular cyclization over 1 h using a two-phase system (H2O/CHCl3) containing R4N afforded α-bromo lactones in good yields. This method can be applied at the 10 mmol scale using simple operations. α-Bromo-δ-valerolactone, which is extremely reactive and difficult to isolate, could be isolated and stored in a freezer for about one week using the developed method. Optimizing the solvent for environmentally friendly large-scale syntheses revealed that methyl ethyl ketone (MEK) was as effective. In addition, in situ-generated α-bromo-δ-valerolactone was directly converted into a sulfur-substituted functional lactone without difficulty by reacting it with a sulfur nucleophile in one pot without isolation. This new bromination system is expected to facilitate the industrial use of α-bromolactones as important intermediates.
Synthetic method for glufosinate ammonium
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Paragraph 0034; 0035, (2019/02/04)
The invention relates to a synthetic method for glufosinate ammonium. The synthetic method comprises the following steps: single-bromine substitution, amination, amino protection, chlorination ring opening, Arbuzov reaction and acidizing hydrolysis ammoniation; the single-bromine substitution means triggering alpha-site single-bromine substitution betweengamma-butyrolactone I and bromine under theexistence of catalyst and performing reduced pressure distillation, thereby acquiring a pure intermediate II alpha-bromine-gamma-butyrolactone; phosphorus tribromide is served as the catalyst; amination means triggering amination reaction between alpha-bromine-gamma-butyrolactone II and ammonium hydroxide, and then adding hydrochloric acid and reflowing, thereby acquiring an intermediate IIIalpha-amino-gamma-butyrolactone hydrochloride. The invention has the beneficial effects: 1) low-costgamma-butyrolactone is taken as a raw material, is subjected to single-bromine substitution with bromineand then is subjected to amination reaction with ammonium hydroxide; the adopted raw materials are low-cost and easily acquired; reaction conditions are mild; operation is simple and convenient; safety is high; amplifying production is feasible; reaction yield is high; product purity is high; cost is greatly lowered; the synthetic method is suitable for industrial production.
A method of manufacturing a brominated lacton compd.
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Paragraph 0052; 0079-0081; 0082; 0085; 0086; 0088, (2018/11/22)
PROBLEM TO BE SOLVED: To provide a method for producing a brominated lactone compound inexpensively and efficiently.SOLUTION: This method for producing a brominated lactone compound includes a bromination step of making bromine react with a lactone compound represented by formula (1) (in the formula, R represents 3-5C linear hydrocarbon group, wherein the hydrocarbon group may be replaced with a hydrocarbon group, carbonyl, oxo, amino, hydroxyl, alkoxyl, acyl, acyloxy or a halogen atom, while one or more hydrogen atoms are bonded to a carbon which is the nearest to a ketone group adjacent to R among carbons constituting R). The bromination step is performed in the presence of at least one catalyst selected from a group comprising sulfur and a sulfur compound.
Process for treating homoserin compounds
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Paragraph 0095; 0109-0114, (2017/01/02)
The present invention relates to the preparation of a useful compound which can be used as an intermediate product for preparing an important compound in the industrial field from a homoserine-based compound and provides a process for treating a homoserine-based compound, capable of simply mass producing a useful compound from a homoserine-based compound with excellent efficiency.(AA) Homoserine-based compound(BB) Product(CC) GBL derivative(DD) Halo-GBL(EE, FF, GG) GBL puranone(HH) Puranone(II) Dialkyl succinate(JJ) Step 1(KK) Step 2(LL) Step 3(MM) Step 4(NN) Step 5(OO) Step 6(PP) Step 7COPYRIGHT KIPO 2016
Synthesis and in vitro antitumor activity of new butenolide-containing dithiocarbamates
Wang, Xiao-Juan,Xu, Hai-Wei,Guo, Lin-Lin,Zheng, Jia-Xin,Xu, Bo,Guo, Xiao,Zheng, Chen-Xin,Liu, Hong-Min
scheme or table, p. 3074 - 3077 (2011/06/26)
Three series of butenolide-containing dithiocarbamates were designed and synthesized. Their anti-tumor activity in vitro was evaluated. Among them compound I-14 exhibited broad spectrum anti-cancer activity against five human cancer cell lines with IC50 30 μM. Structure-activity relationship analysis showed that the introduction of dithiocarbamate side chains on the C-3 position of butenolide was crucial for anti-tumor activity.
Concise total synthesis of (-)-8-epigrosheimin
Yang, Haishen,Gao, Yuzhe,Qiao, Xiaoxiao,Xie, Longguan,Xu, Xiaohua
supporting information; experimental part, p. 3670 - 3673 (2011/09/15)
A highly efficient route was developed to synthesize (-)-8-epigrosheimin in four steps from aldehyde 2 based on a substrate-controlled method. The key steps of the synthesis included (1) a stereo- and regioselective allylation addition, (2) an intramolecular translactonization, and (3) an aldehyde-ene cyclization.
Efficient synthesis of an A-B-C-tricycle fragment for a structural model of tolyporphin
Hu, Bing C.,Zhou, Wei Y.,Liu, Zu L.,Cai, Chao J.,Xu, Shi C.
scheme or table, p. 89 - 100 (2010/11/18)
An efficient stereocontrolled synthesis of an A-B-C-tricycle fragment 7 for a structural model of tolyporphin 3 is described. All the rings were prepared from readily available starting materials. One of the two key steps is a selective ring-opening reaction of the lactone cycle in bicyclolactam-lactone 17 to cyanopyrrolidone 18, which introduces the chirality into synthetic compounds. The other key step is the combination of A ring with B-C-bicycle via a two-time Eschenmoser sulfide contraction. A-B-C-tricycle fragment 7 allows a new approach toward tolypophin compounds and other uroporphinoids.
Method for the Production of D,L-2-Hydroxy-4-Alkylthio Butyric Acid
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Page/Page column 4, (2009/12/28)
The present invention relates to a process for preparing compounds of the formula (I) by reacting compounds of the formula (II) with thiolates (RS)nM. The present invention further relates to a process for preparing compounds of the formula (II) from γ-butyrolactone.
Total synthesis of 4″O-acetylmananthoside B, Part I: Synthesis and tentative ozonolysis of a cyclohexadiene derivative
Zhao, Guilong,Jia, Jiong,Liu, Junzhi,Wang, Jianwu
, p. 3821 - 3828 (2007/10/03)
A cyclohexadiene derivative cis-N,N-diethyl-2-benzyloxymethyl-1,2- dihydrobenzamide 8 was constructed from γ-butyrolactone I for the total synthesis of a natural product 4″-O-acetylmananthoside B, which was reported to display significant cytotoxic activity. Preliminary ozonolysis of 8 for further synthetic purposes was also carried out. Copyright Taylor & Francis Group, LLC.
