- Synthesis and properties of optically active phenoxypropionates having various cores
-
Optically active phenoxypropionates having a variety of cores were synthesized and the effect of the different core structures on the spontaneous polarization (Ps) values was investigated. The results indicate that the core structure has a great influence on the Ps value and compound 3 in which a chiral group attached to the 5-phenyl side of the 2,5-diphenylpyrimidine core showed the largest Ps of 240 nC/cm2. The ability as a chiral dopant for ferroelectric liquid crystal (FLC) were also evaluated. It was found that compound 3 was the most interesting, because the doping of compound 3 induced large Ps and wide tilt angle and this FLC mixture showed short response time. Moreover, the Sc range of host liquid crystal mixture are slightly extended by doping of compound 3.
- Sugita,Toda,Teraji,Murayama,Ishikawa
-
-
Read Online
- Preparation method of octyl (R)-2-(4-chloro-2-methylphenoxy) propionate root retarder
-
The invention discloses a preparation method of octyl (R)-2-(4-chloro-2-methylphenoxy) propionate which can be used as a root retarder. The preparation method comprises the following steps: with ethyl L-lactate as a raw material, sulfonating together with p-toluenesulfonyl chloride to obtain a corresponding sulfonyl ester compound; etherifying the sulfonyl ester compound and 4-chloro-o-cresol to obtain a corresponding aromatic ether ester compound; and finally, performing transesterification on the ether ester compound and n-octyl alcohol to obtain octyl (R)-2-(4-chloro-2-methylphenoxy) propionate. Octyl (R)-2-(4-chloro-2-methylphenoxy) propionate prepared by the preparation method provided by the invention is high in optical content, relatively small in optical loss of raw materials and relatively high in yield. The invention establishes a reaction system with the characteristics of simple preparation process, mild reaction condition and low cost, so that the problems that the compound is imported and has a scarce source are solved to a certain extent.
- -
-
Paragraph 0030; 0031; 0036-0053; 0141; 0142
(2018/04/01)
-
- Preparation method of quizalofop-P-ethyl
-
The invention provides a preparation method of quizalofop-P-ethyl. Ethyl S(-)-tosyllactate is prepared from p-toluenesulfonyl chloride and L-ethyl lactate through a reaction, and quizalofop-P-ethyl is prepared from ethyl S(-)-tosyllactate and 6-chloro-2-(4-hydroxyphenoxy) quinoxaline through a reaction. Ethyl S(-)-tosyllactate is prepared from liquid organic tertiary amine as alkali through reaction in a solvent-free and desiccant-free system, and hydrolysis of L-ethyl lactate is avoided, so that the content of impurities in p-toluenesulfonyl chloride is reduced, the content of impurities in quizalofop-P-ethyl is further reduced, and the chemical content of obtained quizalofop-P-ethyl is 98% or higher, the optical purity is high (R/S is larger than 99/1); operating procedures are simplified, and the production cost is reduced.
- -
-
Paragraph 0038; 0039; 0040; 0041; 0045 0052-0054
(2017/03/28)
-
- A Reactive, Rigid GdIII Labeling Tag for In-Cell EPR Distance Measurements in Proteins
-
The cellular environment of proteins differs considerably from in vitro conditions under which most studies of protein structures are carried out. Therefore, there is a growing interest in determining dynamics and structures of proteins in the cell. A key factor for in-cell distance measurements by the double electron–electron resonance (DEER) method in proteins is the nature of the used spin label. Here we present a newly designed GdIII spin label, a thiol-specific DOTA-derivative (DO3MA-3BrPy), which features chemical stability and kinetic inertness, high efficiency in protein labelling, a short rigid tether, as well as favorable spectroscopic properties, all are particularly suitable for in-cell distance measurements by the DEER method carried out at W-band frequencies. The high performance of DO3MA-3BrPy-GdIII is demonstrated on doubly labelled ubiquitin D39C/E64C, both in vitro and in HeLa cells. High-quality DEER data could be obtained in HeLa cells up to 12 h after protein delivery at in-cell protein concentrations as low as 5–10 μm.
- Yang, Yin,Yang, Feng,Gong, Yan-Jun,Chen, Jia-Liang,Goldfarb, Daniella,Su, Xun-Cheng
-
supporting information
p. 2914 - 2918
(2017/03/14)
-
- Synthesis method of chiral fenoxanil
-
The invention relates to a synthesis method of chiral fenoxanil. The synthesis method of the chiral fenoxanil is characterized in that chiral ethyl lactate is subjected to sulfonylation reaction to obtain sulfonic acid ester; the sulfonic acid ester reacts with 2,4-dichlorophenol to generate 2-(2,4-dichlorophenoxy) ethyl propionate; the 2-(2,4-dichlorophenoxy) ethyl propionate and 2,-amino-2,3-dimethyl nitrile are subjected to ammonia ester exchange reaction to generate corresponding chiral fenoxanil, wherein the molar ratio of the 2-(2,4-dichlorophenoxy) ethyl propionate to the 2,-amino-2,3-dimethyl nitrile is 1:1 and the reaction temperature is 60 to 85 DEG C. The method is simple in synthesis route, hydrolysis and chlorination are not needed, little waste water and waste gas are generated, a high environmentally-friendly benefit is achieved, the production cost is greatly reduced, the condition is mild, the fenoxanil with optical chirality can be synthesized in an oriented mode by selecting different configuration of ethyl lactate, and important significance of further exploring the optical property of the fenoxanil is achieved.
- -
-
Paragraph 0022; 0025
(2017/02/28)
-
- Step-by-step evaporation crystallization separation and recovery in the waste water and the toluene sulfonic acid potassium carbonate (by machine translation)
-
The present invention (the name is: step-by-step evaporation crystallization separation and recovery of waste water in potassium carbonate and paratoluene sulfonic acid potassium) relates to a potassium carbonate, potassium bicarbonate and paratoluene sulfonic acid potassium separation and recovery process. This mixture can be separated by the following method: in the waste water with the potassium bicarbonate is added in equimolar potassium hydroxide, potassium carbonate is converted into potassium carbonate, then evaporate and a proper amount of water, lowering the temperature to the appropriate temperature constant temperature, filtering the insoluble solid is paratoluene sulfonic acid potassium, drying the spare; filter the resulting liquid to evaporate to dry, drying to obtain potassium carbonate. Recovering the resulting potassium P-toluenesulfonic acid in an appropriate solvent, under appropriate temperature, by reaction with the appropriate reagent to the toluene sulfonyl chloride, with L - lactic acid ethyl ester in the presence of an appropriate acid obtained by the reaction of L - lactic acid ethyl ester tosylates. (by machine translation)
- -
-
Paragraph 0009
(2017/07/26)
-
- L-P-toluene sulfonamido lactic acid ethyl ester synthetic method
-
The invention discloses a synthetic method of L-p-toluenesulfonyl ethyl lactate. The synthetic method is characterized in that para-toluensulfonyl chloride, an acid-binding agent and a catalyst are mixed in a solvent, and then cooled below 0 DEG C, then L-ethyl lactate is slowly added and then a heat-preserving reaction is carried out at a temperature ranging from -15 DEG C and 5 DEG C after addition is finished, and finally, the L-p-toluenesulfonyl ethyl lactate is obtained, wherein the acid-binding agent is sodium hydroxide or potassium hydroxide. According to the synthetic method, no repugnant substance is utilized, the L-p-toluenesulfonyl ethyl lactate having the content of more than 98% can be obtained under relatively mild conditions, and the yield of the L-p-toluenesulfonyl ethyl lactate is above 98%.
- -
-
Paragraph 0017; 0018
(2017/02/09)
-
- Preparing method of quizalofop-p-ethyl preparation
-
The invention belongs to the field of pesticides, and provides a preparing method of a quizalofop-p-ethyl preparation. The preparing method of the quizalofop-p-ethyl preparation is characterized in that common preparing of the quizalofop-p-ethyl preparation is replaced, and a one-step method is adopted, namely, quizalofop-p-ethyl raw powder cannot be synthesized and produced, and the quizalofop-p-ethyl preparation can be directly produced and prepared. The preparing method of the quizalofop-p-ethyl preparation, provided by the invention, has the maximum advantages that resource integration is realized, crystallizing and drying steps are removed, the labor amount is reduced, the yield is increased, the production cost is reduced, and mother liquor-black oil is prevented from being generated. The preparing method can be used for preparing the following preparations: 5 to 25 percent of quizalofop-p-ethyl EC (Emulsifiable Concentrate), 5 to 15 percent of quizalofop-p-ethyl microemulsion, 5 to 10 percent of quizalofop-p-ethyl EW (Emulsion in Water), 5 to 50 percent of quizalofop-p-ethyl dry suspension concentrate, 5 to 20 percent of quizalofop-p-ethyl water suspension concentrate, quizalofop-p-ethyl oil suspension concentrate, quizalofop-p-ethyl composite EC, composite microemulsion, composite EW, composite dry suspension concentrate, composite water suspension concentrate and composite oil suspension concentrate.
- -
-
Paragraph 0074
(2017/03/08)
-
- A method for preparing quizalofop
-
The invention belongs to the technical field of pesticide synthesis, and relates to a preparation method for quizalofop-p-ethyl, in particular to a preparation method for quizalofop-p-ethyl with R content of over 95 percent. The preparation method comprises the following steps of: preparing a chiral intermediate through monomolecular substitution reaction of L-ethyl lactate and paratoluensulfonyl chloride in an organic solvent by using two-step substitution reaction under the condition of excess chiral monomers; filtering to remove excess water absorbing agent and salt produced by reaction, washing excess L-ethyl lactate and acid-binding agent and distilling to remove the solvent; performing bimolecular substitution reaction on the chiral intermediate and 6-chloro-2-(4-hydroxyl phenoxyl) quinoxaline; and purifying to obtain R quizalofop-p-ethyl with high optical purity and stability, wherein the product yield and purity are high, the optical content is greater than 99 percent, R content reaches over 95 percent, and the yield is greater than 92 percent. The method has the advantages of simple process, easiness for control, short reaction period, long energy consumption and greatly reduced process cost.
- -
-
Paragraph 0037; 0038
(2017/04/03)
-
- Argentivorous molecules bearing three aromatic side arms: Synthesis of triple-armed cyclens and their complexing property towards Ag+
-
Triple-armed cyclens bearing three aromatic side-arms were prepared in three steps from (3R,5S)-3,5-dimethyl-1,4,7,10-tetraazacyclododecane-2,6-dione, and the Ag+-ion-induced 1H NMR and UV-vis spectral changes and X-ray structures suggested that the aromatic side-arms cover the Ag+ incorporated into the ligand cavities like an insectivorous plant (Venus flytrap).
- Habata, Yoichi,Kizaki, Juli,Hosoi, Yasuhiro,Ikeda, Mari,Kuwahara, Shunsuke
-
p. 1170 - 1177
(2015/02/02)
-
- Stereoselective synthesis of γ-lactams from imines and cyanosuccinic anhydrides
-
A reaction between imines and anhydrides has been developed with chiral disubstituted anhydrides and chiral imines. The synthesis of highly substituted γ-lactams with three stereogenic centers, including one quaternary center, proceeds at room temperature in high yield and with high diastereoselectivity in most cases. Enantiomerically pure alkyl-substituted anhydrides proceed with no epimerization, thus providing access to enantiomerically pure penta-substituted lactam products.
- Tan, Darlene Q.,Younai, Ashkaan,Pattawong, Ommidala,Fettinger, James C.,Cheong, Paul Ha-Yeon,Shaw, Jared T.
-
supporting information
p. 5126 - 5129
(2013/10/22)
-
- Enantioselective α-tosyloxylation of ketones catalyzed by spirobiindane scaffold-based chiral iodoarenes
-
Enantiomerically pure iodoarene (S)-2 and its derivatives (S)-3 to (S)-18 with a spirobiindane scaffold have been synthesized. The evaluation of these new chiral iodoarenes as catalysts in the enantioselective α-tosyloxylation of ketones was performed using m-CPBA as a stoichiometric oxidant, and the synthetically useful α-tosyloxylated ketones were obtained in up to 58% enantiomeric excess (ee).
- Yu, Jun,Cui, Jian,Hou, Xue-Sen,Liu, Shan-Shan,Gao, Wen-Chao,Jiang, Shan,Tian, Jun,Zhang, Chi
-
scheme or table
p. 2039 - 2055
(2012/03/11)
-
- Rapid and efficient synthesis of (R)-aryloxypropionic acid esters under microwave irradiation
-
A series of (R)-(+)-ethyl aryloxypropionates (4a-4p) have been synthesized by the reaction of substituted phenols with ethyl (S)-(-)-tosyloxy lactate under the conditions of microwave irradiation and without solvents. The reaction conditions have been optimized. A good method for the preparation of (R)-(+)-ethyl aryloxypropionate was developed, with good yields, high enantiomer excess, short reaction times, easy workup, and simple procedure. Copyright Taylor & Francis Group, LLC.
- Ochal, Zbigniew,Durka, Krzysztof,Banach, Lukasz
-
experimental part
p. 3209 - 3213
(2010/12/24)
-
- Enantioselective synthesis of (R)-propylene carbonate from ethyl (S)-lactate
-
We report a three-step synthesis of (R)-propylene carbonate from inexpensive, chiral ethyl (S)-lactate. The synthesis involves a borohydride ester reduction and an unusual intramolecular displacement reaction by a carbonate anion. The procedure is simple and reliable, resulting in (R)-propylene carbonate in approximately 60% overall yield with ≥98% ee. Georg Thieme Verlag Stuttgart.
- Whitaker, John M.,Ronald, Robert C.
-
scheme or table
p. 1403 - 1404
(2010/02/16)
-
- tert-butyl (2S)-(p-tolylsulfonyloxy)propionate - A suitable reagent for the direct alkylation of indole derivatives
-
A new method is proposed for the synthesis of indole derivatives containing a chiral substituent at the nitrogen atom, which includes the direct alkylation of indole derivatives with tert-butyl (2S)-(p-tolylsulfonyloxy)propionate, obtained from commercial ethyl (S)-lactate with subsequent conversion to the corresponding p-toluenesulfonyloxy derivative by hydrolysis, and esterification.
- Kurkin,Belov,Yurovskaya
-
experimental part
p. 1123 - 1128
(2009/05/26)
-
- Stereospecific synthesis and bio-activity of novel β3-adrenoceptor agonists and inverse agonists
-
Since it is widely distributed into the body, β3-adrenoceptor is becoming an attractive target for the treatment of several pathologies such as obesity, type 2 diabetes, metabolic syndrome, cachexia, overactive bladder, ulcero-inflammatory disorder of the gut, preterm labour, anxiety and depressive disorders, and heart failure. New compounds belonging to the class of arylethanolamines bearing one or two stereogenic centres were prepared in good yields as racemates and optically active forms. They were, then, evaluated for their intrinsic activity towards β3-adrenoceptor and their affinity for β1- and β2-adrenergic receptors. Stereochemical features were found to play a crucial role in determining the behaviour of such compounds. In particular, α-racemic, (αR)- and (αS)-2-{4-[2-(2-hydroxy-2-phenylethylamino)ethyl]phenoxy}-2- methylpropanoic acid, (α-rac, β-rac)-, (αR, βS)- and (αR, βR)- 2-{4-[2-(2-hydroxy-2-phenylethylamino)ethyl]phenoxy}propanoic acid were found to be endowed with β3-adrenoceptor agonistic activity. Whereas, (αS, βS)- and (αS, βR)-2-{4-[2-(2-hydroxy-2-phenylethylamino)ethyl]phenoxy}propanoic acid behaved as β3-adrenoceptor inverse agonists. Such compounds showed no affinity for β1- and β2-adrenergic receptor, respectively. Thus, resulting highly selective β3-adrenoceptor ligands.
- Perrone, Maria Grazia,Santandrea, Ernesto,Bleve, Laura,Vitale, Paola,Colabufo, Nicola Antonio,Jockers, Ralf,Milazzo, Ferdinando Maria,Sciarroni, Anna Floriana,Scilimati, Antonio
-
p. 2473 - 2488
(2008/09/21)
-
- Hydrogen bonding in enantiomeric versus racemic mono-carboxylic acids; a case study of 2-Phenoxy-Propionic acid
-
The structural and thermodynamic backgrounds for the crystallization behaviour of racemates have been investigated using 2-phenoxypropionic acid (PPA) as an example. The racemate of PPA behaves normally and forms a racemic compound that has a higher melting point and is denser than the enantiomer. Low-temperature crystal structures of the pure enantiomer, the enantiomer cocrystallized with n-alkanes and the racemic acid showed that hydrogen-bonded dimers that form over crystallographic symmetry elements exist in all but the structure of the pure enantiomer. A database search for optically pure chiral mono-carboxylic acids revealed that the hydrogen-bonded cyclic dimer is the most prevalent hydrogen-bond motif in chiral mono-carboxylic acids. The conformation of PPA depends on the hydrogen-bond motif; the antiplanar conformation relative to the ether group is associated with a catemer hydrogen-bonding motif, whereas the more abundant synplanar conformation is found in crystals that contain cyclic dimers. Other intermolecular interactions that involve the substituent of the carboxylic group were identified in the crystals that contain the cyclic dimer. This result shows how important the nature of the substituent is for the crystal packing. The differences in crystal packing have been related to differences in melting enthalpy and entropy between the racemic and enantiomeric acids. In a comparison with the equivalent 2-(4-chlorophenoxy)-propionic acids, the differences between the crystal structures of the chloro and the unsubstituted acid have been identified and related to thermodynamic data.
- Sorensen, Henning Osholm,Larsen, Sine
-
p. 132 - 140
(2007/10/03)
-
- Silver(I) oxide-mediated facile and practical sulfonylation of alcohols
-
Primary and secondary alcohols were efficiently sulfonylated in the presence of silver(I) oxide and potassium iodide in dichloromethane. The sulfonylation occurs under mild, neutral reaction conditions. The ease of isolation of the final product presents a marked advantage over the known methodologies.
- Bouzide, Abderrahim,LeBerre, Nicolas,Sauvé, Gilles
-
p. 8781 - 8783
(2007/10/03)
-
- New chiral inhibitors of induced platelet aggregation: The enantiomeric specificity of (R)- and (S)-methyl and ethyl esters of 1-{4-[(1-hydroxycarbonyl)-ethoxy]-benzyl}-1H-1,2,3-triazole as a tool for determining their biological target
-
The synthesis of title enantiomers was accomplished and their biological behaviour as inhibitors of rabbit platelet aggregation process induced by ADP and arachidonic acid was determined. Structure-activity comparison with that of SM-12502 [(2R,5S)-(+)3,5-dimethyl-2-(3-pyridyl)-thiazolidin-4-one hydrochloride] and Dazoxiben {4-[2-(1H-imidazol-1-yl)-ethoxy]-benzoic acid} allowed us to formulate the possible capability for the synthesized compounds to interact with the biological targets of the model molecules.
- Biagi,Giorgi,Livi,Scartoni,Catalani,Gervasi
-
p. 761 - 766
(2007/10/03)
-
- Novel juvenoids of the 2-(4-hydroxybenzyl)cyclohexan-1-one series
-
A series of insect juvenile hormone analogs (juvenoids) was synthesized and studied. The basic skeleton of these juvenoids contains three rings and a short aliphatic subunit and bears two or three chiral centers (depending on the appropriate structure; see 6-9). The chiral center located in the 1,2-diphenoxypropane subunit has the configuration (RS), (R) (a series), or (S) (b series). The juvenoids were subjected to a biological screening, the preliminary results of which are briefly described.
- Wimmer,Saman,Francke
-
p. 502 - 508
(2007/10/02)
-
- (S)-(-)-ethyl lactate as a convenient precursor for synthesis of chiral liquid crystals
-
A strategy is presented for synthesis of optically active precursors derived from (S)-(-)-ethyl lactate for use in synthesis of chiral liquid crystals.
- Merlo,Gallardo
-
p. 2159 - 2169
(2007/10/02)
-
- Oxime Ethers as Potential Juvenoids: Synthesis of Optical Isomers
-
Two racemic juvenoids 5 and 6 and their optical isomers 10, 11, 17 and 18 having chiral centres in the aliphatic side chain were synthetized.The second chiral centre in the molecules remained racemic in all derivatives prepared.The absolute configurations of the optically active centres of the enantiomers were determined on the basis of (1)H-NMR spectral evaluation of the diastereoisomeric MTPA esters 12, 13, 19 and 20 derived from the intermediate alcohols 8 and 15.The optical purity was established by an HPLC analysis of the corresponding MTPA esters.The 1H-NMR spectra of all compounds as well as the CD spectra of all chiral isomers were measured and discussed.
- Wimmer, Zdenek,Vasickova, Sona,Saman, David,Romanuk, Miroslav
-
p. 847 - 852
(2007/10/02)
-
- Oxime Ethers: New Potent Insect Growth Regulators
-
Oxime ethers containing a 4-phenoxyphenoxy group in the molecules were synthesized and their insect growth regulating (IGR) activities were studied.Of these new IGR's, propionaldehyde oxime O-2-(4-phenoxyphenoxy)ethyl ether and propionaldehyde oxime O-2-(phenoxyphenoxy)propyl ether were found to be most effective, having much higher activities than methoprene against larvae of Culex pipiens pallens and Musca domestica by the immersion method and medium method, respectively.In addition, the effects of steric isomerism of these compounds were examined; their IGR activities were found to have a close relationship to the juvenile hormone activity by the Galleria wax test.
- Ohsumi, Tadashi,Hatakoshi, Makoto,Kisida, Hirosi,Matsuo, Noritada,Nakayama, Isamu,Itaya, Nobushige
-
p. 3197 - 3202
(2007/10/02)
-
- Results of Process Research. I. Synthesis of O-propionyl>-acetone oxime
-
Efficient and simple procedures for the preparation of O--propionyl>-oxime derivatives 7b-e have been developed.The alkylation of 4-phenol (11) with 7d, the final step of a technical synthesis of 1, has been studied in detail.
- Imfeld, Marquard,Suchy, Milos,Vogt, Peter,Lukac, Teodor,Schlageter, Markus,Widmer, Erich
-
p. 1233 - 1241
(2007/10/02)
-
- The Synthesis of Chiral Dimethyl Substituted Macrocyclic Polyether-Diester Ligands (1)
-
A new series of chiral macrocyclic polyether-diester ligands has been prepared from four chiral dimethyl substituted tetraethylene glycols (15a,b,16,17) and 2,6-pyridinecarbonyl chloride (products 5a-7), diglycolyl chloride (products (8-10), thiadiglycolyl chloride (product 11), 2,5-furandicarbonyl chloride (product 12), 4-chloro-2,6-pyridinedicarbonyl chloride (product 13), and 4-methoxy-2,6-pyridinedicarbonyl chloride (product 14).The chiral dimethyl substituted tetraethylene glycols (15a-17) were prepared from ethyl(S)-lactate.
- Jones, Brian A.,Bradshaw, Jerald S.,Izatt, Reed M.
-
p. 551 - 556
(2007/10/02)
-
- Synthesis and Herbicidal Activity of the D- and L-Methyl 2--propionate Enantiomers
-
The D- and L-enantiomers of the wild oat herbicide diclofop-methyl (title compound) were prepared utilizing resolution operations and by synthetic routes with optically active compounds as starting material.The dextro-rotatory product which the D(R)-configuration can be attributed to, was found to be the herbicidally active species. - Keywords: Phenoxy-phenoxy-propionic Acid Ester, Diclofop-methyl, Stereoisomers, Grass Herbicide
- Nestler, Hans Juergen,Bieringer, Hermann
-
p. 366 - 371
(2007/10/02)
-
