- Tungsten complex induced dehydration of 2,3-dihydroxycarboxylic acids to α-keto acids
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In the absence of added base, WOCl4 induces rapid dehydration of the title compounds to give α-keto acids. A mechanism is suggested based on a neighboring group effect.
- Yu,Schwartz
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Read Online
- Diversity-oriented synthesis of amide derivatives of tricyclic thieno[2,3-d]pyrimidin-4(3H)-ones and evaluation of their influence on melanin synthesis in murine B16 cells
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A diversity-oriented synthesis of amide-containing thieno[2,3-d]pyrimidin-4(3H)-ones is reported. All compounds were tested for their influence on melanin synthesis in murine B16 cells. The azepine fragment in thieno[2,3-d]pyrimidin-4(3H)-one skeleton significantly increases the melanin content.
- Nie, Li Fei,Huang, Guozheng,Bozorov, Khurshed,Zhao, Jiangyu,Niu, Chao,Sagdullaev, Shamansur S.,Aisa, Haji A.
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Read Online
- Design and synthesis of novel triazole derivatives containing γ-lactam as potential antifungal agents
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A series of novel triazole derivatives containing γ-lactam were designed and synthesized, and their structures were confirmed by 1H NMR, 13C NMR and HRMS. The in vitro antifungal activities of the target compounds were evaluated. The results showed that all of the compounds exhibited stronger activity against the six clinically important fungi tested than fluconazole. 3D and 3E showed comparative activity against the fungi tested except for Candida glabrata and Aspergillus fumigatus as voriconazole. In addition, the docking model for 2A and CYP51 was investigated.
- Xu, Yuan-Yuan,Qian, An-Ran,Cao, Xu-Feng,Ling, Chen-Yu,Cao, Yong-Bing,Wang, Rui-Lian,Li, Yi-Su,Yang, Yu-She
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Read Online
- Method for synthesizing ethyl cucurbituride lactone spice
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Compared with the existing similar products, the method comprises the following steps: preparing 2 -oxobutyric acid ethyl ester by Grignard reaction under the condition of absolute ethyl acetate as a starting raw material and carrying out Grignard reaction on potassium carbonate. After the needed carbon skeleton is cyclized under the action of acetaldehyde, ethylcucurbituric acid lactone is obtained, and the technological process is reduced. The reaction solvent and the extractant are recycled, so that the cost is reduced, the purity of the product is 98.36% through gas chromatography, and higher reaction yield is ensured.
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Paragraph 0025-0036
(2021/11/14)
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- Synthesizing method for dimethyl-3-hydroxy-2,5-dihydrofuran-2-one spice
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The invention discloses a synthesizing method for dimethyl-3-hydroxy-2,5-dihydrofuran-2-one spice, and relates to the technical field of specie synthesis. According to the synthesizing method, the dimethyl-3-hydroxy-2,5-dihydrofuran-2-one is obtained by taking diethyl oxalate as a starting material, preparing 2-oxo-ethyl butyrate through a Grignard reaction in the absence of water and under the protection of nitrogen; cyclizing a required carbon skeleton under the action of potassium carbonate and acetaldehyde to obtain the dimethyl-3-hydroxy-2,5-dihydrofuran-2-one. A reaction solvent and an extracting agent can be used after being recycled; the process flow is reduced; the reaction yield is relatively high.
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Paragraph 0042-0052
(2019/10/23)
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- Production method of dimethylhydroxyfuranone synthetic perfume
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The invention discloses a production method of dimethylhydroxyfuranone synthetic perfume, and relates to the technical field of perfume production. The production method comprises the steps that anhydrous tetrahydrofuran is taken as a solvent, diethyl oxalate is subjected to Grignard reaction under the nitrogen protection condition, after extracting and washing through dichloromethane and drying through anhydrous sodium sulfate, the dichloromethane is recovered to be applied, and decompressed distillation is conducted to collect 2-ethyl oxybutyrate; and then absolute ethyl alcohol is taken asa solvent, the 2-ethyl oxybutyrate is cyclized under the effects of potassium carbonate and acetaldehyde, ethyl alcohol is recovered at the normal pressure, after extracting and washing through the dichloromethane and drying through the anhydrous sodium sulfate, the dichloromethane is recovered to be applied, decompressed distillation is conducted, and thus a dimethylhydroxyfuranone synthetic perfume product is obtained. The production method is clear in process control parameter and good in process repeatability, the solvent is reasonably recovered and reutilized, the production cost is lowered while environment pollution is reduced, the obtained product, namely the dimethylhydroxyfuranone synthetic perfume, is high in yield and purity, and the perfume requirements are met.
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Paragraph 0036-0047; 0057-0068
(2019/11/12)
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- Diastereo- and Enantioselective Synthesis of Fluorine Motifs with Two Contiguous Stereogenic Centers
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The synthesis of chiral fluorine containing motifs, in particular, chiral fluorine molecules with two contiguous stereogenic centers, has attracted much interest in research due to the limited number of methods available for their preparation. Herein, we report an atom-economical and highly stereoselective synthesis of chiral fluorine molecules with two contiguous stereogenic centers via azabicyclo iridium-oxazoline-phosphine-catalyzed hydrogenation of readily available vinyl fluorides. Various aromatic, aliphatic, and heterocyclic systems with a variety of functional groups were found to be compatible with the reaction and provide the highly desirable product as single diastereomers with excellent enantioselectivities.
- Ponra, Sudipta,Rabten, Wangchuk,Yang, Jianping,Wu, Haibo,Kerdphon, Sutthichat,Andersson, Pher G.
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supporting information
p. 13878 - 13883
(2018/10/24)
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- Design, synthesis, and evaluation of alkyl-quinoxalin-2(1h)-one derivatives as anti-quorum sensing molecules, inhibiting biofilm formation in aeromonas caviae Sch3
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With the increasing antibiotic resistance of bacterial strains, alternative methods for infection control are in high demand. Quorum sensing (QS) is the bacterial communication system based on small molecules. QS is enables bacterial biofilm formation and pathogenic development. The interruption of QS has become a target for drug discovery, but remains in the early experimental phase. In this study, we synthesized a set of six compounds based on a scaffold (alkyl-quinoxalin-2(1H)-one), new in the anti-QS of Gram-negative bacteria Aeromonas caviae Sch3. By quantifying biofilm formation, we were able to monitor the effect of these compounds from concentrations of 1 to 100 μM. Significant reduction in biofilm formation was achieved by 3-hexylylquinoxalin-2(1H)-one (11), 3-hexylylquinoxalin-2(1H)-one-6-carboxylic acid (12), and 3-heptylylquinoxalin-2(1H)-one-6-carboxylic acid (14), ranging from 11% to 59% inhibition of the biofilm. This pilot study contributes to the development of anti-QS compounds to overcome the clinical challenge of resistant bacteria strains.
- Bl?cher, René,Ramírez, Ariel Rodarte,Castro-Escarpulli, Graciela,Curiel-Quesada, Everardo,Reyes-Arellano, Alicia
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- 8-hexyl-thieno-[3',2':3,4] benzo[1,2-c] carbazole compound and synthesizing method thereof
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The present invention relates to a 8-hexyl-thieno-[3',2':3,4] benzo[1,2-c] carbazole compound and a synthesizing method thereof. The 8-hexyl-thieno-[3',2':3,4] benzo[1,2-c] carbazole compound with high solubility is prepared from carbazole derivatives and thiophene derivatives which are used as raw materials by using a method of photocatalysis loop closing. The synthesizing method is simple in reaction operation and post-processing and easy in popularization and application. The 8-hexyl-thieno-[3',2':3,4] benzo[1,2-c] carbazole compound can be widely applied in the fields of organic electroluminescence, organic field-effect transistors, organic second-order nonlinerity, chiral liquid crystals, biological medicines and the like.
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Paragraph 0099; 0100; 0101
(2017/08/02)
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- Azacyclothiophene[2,3-d]pyrimidone sulfonamide derivatives and use thereof
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The invention relates to azacyclothiophene[2,3-d]pyrimidone sulfonamide derivatives and a use thereof. The azacyclothiophene[2,3-d]pyrimidone sulfonamide compounds are 9a-9h, 10a-10j and 11a-11e are synthesized from diethyl oxalate through a six-step reaction. The influences of above 23 compounds on the melanin generation amount in mouse B16 cells and the inhibition activity of acetylcholinesterase and butyrylcholine esterase are investigated, and a reulst of the influences on the melanin generation amount in the mouse B16 cells shows that the compounds have a better melanin generation promotion effect than positive control (no-treatment group), and can be clinically used for preparing leucoderma treatment medicines; an acetylcholinesterase inhibition activity screening result shows that compared with negative control, the acetylcholinesterase inhibition rate of the compounds 10f, 11a and 11e reaches 30% or above; and a butyrylcholine esterase inhibition activity screening result shows that compared with negative control, the butyrylcholine esterase inhibition rate of the compounds 9e and 11e reaches 30% or above.
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Paragraph 0099; 0100; 0101
(2017/08/14)
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- Synthesis and biological evaluation of novel sulfonamide derivatives of tricyclic thieno[2,3-d]pyrimidin-4(3H)-ones on melanin synthesis in murine B16 cells
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Phototherapy with psoralens as photosensitizers is the commonly used method for the treatment of vitiligo. Considering the structure similarity between psoralens and thieno[2,3-d]pyrimidinones, a series of novel sulfonamide derivatives containing tricyclic thieno[2,3-d]pyrimidinone were synthesized and evaluated for melanin synthesis in murine B16 cells. All new compounds were characterized by 1H NMR, 13C NMR, IR and HRMS (ESI). Among them, 6 compounds demonstrated excellent activity than positive control (8-methoxylpsoralen, 8-MOP) with more than 1.5-fold potency. Compound 11w with dichloro substitution at meta-positions in the benzenesulfonyl moiety was the most potent one (658.3?±?8.7%), exhibiting 5.0-fold stronger activity?than 8-MOP (130.9?±?8.6%). The difluoro analog compound 11o increased melanin synthesis in murine B16 cells with a 4.35-fold potency as compared to 8-MOP. These compounds may serve as lead compounds for further drug discoveries for the treatment of vitiligo.
- Nie, Li Fei,Bozorov, Khurshed,Niu, Chao,Huang, Guozheng,Aisa, Haji Akber
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p. 6835 - 6843
(2017/10/06)
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- Melanin-Concentrating Hormone Receptor 1 Antagonists Lacking an Aliphatic Amine: Synthesis and Structure-Activity Relationships of Novel 1-(Imidazo[1,2-a]pyridin-6-yl)pyridin-2(1H)-one Derivatives
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Aiming to discover melanin-concentrating hormone receptor 1 (MCHR1) antagonists with improved safety profiles, we hypothesized that the aliphatic amine employed in most antagonists reported to date could be removed if the bicyclic motif of the compound scaffold interacted with Asp123 and/or Tyr272 of MCHR1. We excluded aliphatic amines from our compound designs, with a cutoff value of pKa 8, and explored aliphatic amine-free MCHR1 antagonists in a CNS-oriented chemical space limited by four descriptors (TPSA, ClogP, MW, and HBD count). Screening of novel bicyclic motifs with high intrinsic binding affinity for MCHR1 identified the imidazo[1,2-a]pyridine ring (represented in compounds 6a and 6b), and subsequent cyclization of the central aliphatic amide linkage led to the discovery of a potent, orally bioavailable MCHR1 antagonist 4-[(4-chlorobenzyl)oxy]-1-(2-cyclopropyl-3-methylimidazo[1,2-a]pyridin-6-yl)pyridin-2(1H)-one 10a. It exhibited low potential for hERG inhibition and phospholipidosis induction as well as sufficient brain concentration to exert antiobesity effects in diet-induced obese rats.
- Igawa, Hideyuki,Takahashi, Masashi,Kakegawa, Keiko,Kina, Asato,Ikoma, Minoru,Aida, Jumpei,Yasuma, Tsuneo,Kawata, Yayoi,Ashina, Shuntaro,Yamamoto, Syunsuke,Kundu, Mrinalkanti,Khamrai, Uttam,Hirabayashi, Hideki,Nakayama, Masaharu,Nagisa, Yasutaka,Kasai, Shizuo,Maekawa, Tsuyoshi
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supporting information
p. 1116 - 1139
(2016/02/23)
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- THIAZOLOPYRIMIDINONES AS MODULATORS OF NMDA RECEPTOR ACTIVITY
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The present invention relates to certain thiazolopyrimidinone compounds for use in modulating NMDA receptor activity, pharmaceutical compositions comprising such compounds and methods of treating neurological and psychiatric conditions.
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Page/Page column 0333
(2015/04/28)
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- Highly chemo-, enantio-, and regioselective synthesis of α,α-disubstituted furanones by Cu-catalyzed conjugate addition
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A highly chemo-, enantio-, and regioselective synthesis of furanones bearing an α,α-disubstituted quaternary stereogenic center is reported. The Cu-catalyzed enantioselective conjugate addition of organoaluminum reagents to unsaturated ketoesters at room temperature and subsequent lactonization took place. Synthetic transformations of furanones represent facile approaches to various cyclic or acyclic compounds bearing a quaternary stereogenic center. Selective chemistry: A highly chemo-, enantio-, and regioselective synthesis of furanones bearing an α,α-disubstituted quaternary stereogenic center is reported (see scheme). Cu-catalyzed enantioselective conjugate addition of organoaluminum reagents to unsaturated ketoesters at room temperature and subsequent lactonization took place.
- Endo, Kohei,Yakeishi, Sayuri,Takayama, Ryotaro,Shibata, Takanori
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supporting information
p. 8893 - 8897
(2014/07/22)
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- Cationic Ir/Me-BIPAM-catalyzed asymmetric intramolecular direct hydroarylation of α-ketoamides
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Asymmetric intramolecular direct hydroarylation of α-ketoamides gives various types of optically active 3-substituted 3-hydroxy-2-oxindoles in high yields with complete regioselectivity and high enantioselectivities (84-98 % ee). This is realized by the use of the cationic iridium complex [Ir(cod) 2](BArF4) and the chiral O-linked bidentate phosphoramidite (R,R)-Me-BIPAM. Carbon's got a brand new bond: Asymmetric intramolecular direct hydroarylation of α-ketoamides gives various optically active 3-substituted 3-hydroxy-2-oxindoles in high yields with complete regioselectivity and high enantioselectivities. This is realized by the use of an asymmetric cationic iridium complex formed in situ (see Scheme).
- Shirai, Tomohiko,Ito, Hajime,Yamamoto, Yasunori
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supporting information
p. 2658 - 2661
(2014/03/21)
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- Alternative method for the synthesis of imidazo[5,1-f][1,2,4]triazin-4(3H)- one - A substrate for the preparation of phosphodiesterase (5) inhibitors
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Imidazo[5,1-f][1,2,4]triazin-4(3H)-ones, as isosteres of purine, are of interest for pharmaceutical research as potential substrates for the synthesis of cGMP-PDE5 inhibitors. We present a novel, alternative method for the synthesis of imidazotriazinones, that differs from the previously reported ones with respect to the method of construction of the triazinone ring in the molecule. The key step in our approach is condensation of an appropriate α-keto-ester with amidrazones, leading to the triazinone heterocycle. Several different substituted imidazolotriazinones have been synthesized in this manner.
- Olszewska, Teresa,Gajewska, Ewa P.,Milewska, Maria J.
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p. 474 - 480
(2013/02/23)
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- HETEROARYL COMPOUNDS AND METHODS OF USE THEREOF
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Provided herein are heteroaryl compounds, methods of their synthesis, pharmaceutical compositions comprising the compounds, and methods of their use. In one embodiment, the compounds provided herein are useful for the treatment, prevention, and/or management of various disorders, such as CNS disorders and metabolic disorders, including, but not limited to, e.g., neurological disorders, psychosis, schizophrenia, obesity, and diabetes.
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Page/Page column 52-53
(2012/07/27)
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- HETEROARYLTHIOMETHYL PYRIDINE DERIVATIVE
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The present invention relates to a compound represented by a formula (I): wherein X is a group represented by or the like; Y is a group represented by or the like; and Ar1 is a group represented by or a pharmaceutically acceptable salt thereof.
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Page/Page column 42
(2010/11/17)
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- NEMATOCIDAL SULFONAMIDES
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Disclosed are compounds of Formula 1 (see "Formula 1"), N-oxides, and salts thereof, wherein Z is O or S; and R1, R2, R3, Q and n are as defined in the disclosure. Also disclosed are compositions containing the compounds of Formula 1 and methods for controlling a parasitic nematode comprising contacting the parasitic nematode or its environment with a biologically effective amount of a compound or a composition of the invention.
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Page/Page column 64
(2010/11/18)
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- (2-Aryl-5-methylimidazol-4-ylcarbonyl)guanidines and (2-aryl-5-methyloxazol-4-ylcarbonyl)guanidines as NHE-1 inhibitors
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A series of (2-aryl-5-methylimidazol-4-ylcarbonyl)guanidines and (2-aryl-5-methyloxazol-4-ylcarbonyl)guanidines were synthesized and evaluated as NHE-1 inhibitors. The structure-activity relationships well matched those of furan derivatives, which were previously investigated. The (2,5-disubstituted)phenyl compounds showed better activities than the other analogues in both imidazole and oxazole compounds. Especially, 2-(2,5-dichlorophenyl)imidazole 52, and 2-(2-methoxy-5-chlorophenyl)imidazole 54 compounds exhibited potent cardioprotective efficacy both in vitro and in vivo as well as high NHE-1 inhibitory activities.
- Lee, Sunkyung,Yi, Kyu Yang,Youn, Sung Jun,Lee, Byung Ho,Yoo, Sung-eun
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scheme or table
p. 1329 - 1331
(2009/10/02)
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- Synthesis of 3-alkylquinoxalin-2(1H)-ones via Grignard reaction
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A two-step procedure has been developed for the synthesis of 3-alkylquinoxalin-2(1H)-ones from o-phenylenediamine and ethyl 2-oxoalkanoates prepared by the Grignard reaction of diethyl oxalate with alkyl bromides. Analogous reaction with α,ω-dibromoalkanes instead of alkyl bromides leads to the formation of 3,3'-(alkane-α,ω-diyl)di[quinoxalin-2(1H) -ones].
- Kalinin,Mamedov
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experimental part
p. 1098 - 1101
(2011/02/26)
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- Preparation and Characterization of [5-13C]-(2S,4R)-Leucine and [4-13C]-(2S,3S)-Valine - Establishing Synthetic Schemes to Prepare Any Site-Directed Isotopomer of L-Leucine, L-Isoleucine and L-Valine
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In this paper a chemo-enzymatic method has been developed that gives access to any isotopomer of the essential amino acids isoleucine and valine. The method gives the correct introduction of the second chiral center in (2S,3S)-isoleucine and allows for discrimination between the two prochiral methyl groups in valine as shown by the preparation of (2S,3S)-[4- 13C] valine. For the preparation of (2S)-leucine in any isotopomeric form, the O'Donnell method to prepare optically active amino acids has been used. The protected glycine scaffold used in this method has been prepared by a strategy that allows access to any isotopomeric form. The preparation of [5-13C]-(2S,4R)-leucine shows that the O'Donnell method in combination with the Evans method to obtain chiral 2-methylpropyl iodide leads to a good discrimination between the two prochiral methyl groups. The O'Donnell strategy for the preparation of α-amino acids is preferred over other methods since the reaction conditions are mild, the chiral auxiliary can be easily recovered and the optically active product can be easily separated. For the preparation of isotopically enriched valine and isoleucine the O'Donnell method is not suitable, because the alkyl substituents involved have a secondary halide substituent which is sterically too hindered to give an effective reaction with the protected glycine. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
- Siebum, Arjan H. G.,Woo, Wei Sein,Lugtenburg, Johan
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p. 4664 - 4678
(2007/10/03)
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- 3-substituted indole antiproliferative angiogenesis inhibitors
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3-Substituted indole carbohydrazides having the formula are useful for inhibiting angiogenesis and cell proliferation. Also disclosed are compositions which inhibit angiogenesis and cell proliferation and methods of inhibiting angiogenesis and cancer in a mammal.
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- Copper-catalyzed enantioselective Henry reactions of α-keto esters: An easy entry to optically active β-nitro-α-hydroxy esters and β-amino-α-hydroxy esters
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The catalytic enantioselective Henry reaction of α-keto esters with nitromethane has been developed. The reaction conditions have been optimized by the screening of different chiral Lewis acids, solvents, and bases, and it was found that the copper(II)-tert-butyl bisoxazoline complex in combination with triethylamine catalyzed a highly enantioselective reaction giving optically active β-nitro-α-hydroxy esters in high yields and with excellent enantiomeric excesses. The scope of the reaction is demonstrated by the reaction of a variety of different α-keto esters. The catalytic enantioselective Henry reaction of β,γ-unsaturated-α-keto esters proceeds as a 1,2-addition reaction exclusively, in contrast to the uncatalyzed reaction where both the 1,2- and 1,4-addition products are formed. It is demonstrated that the β-nitro-α-hydroxy esters can be converted into, e.g., Boc-protected β-amino-α-hydroxy esters in high yields and without loss of optical purity. The mechanism for the reaction is discussed, and it is postulated that both the α-keto ester and nitromethane/nitronate is coordinated to the metal center during the reaction course.
- Christensen, Christina,Juhl, Karsten,Hazell, Rita G.,Jorgensen, Karl Anker
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p. 4875 - 4881
(2007/10/03)
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- 3-substituted indole angiogenesis inhibitors
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3-Substituted indole carbohydrazides having the formula are useful for inhibiting angiogenesis. Also disclosed are angiogenesis-inhibiting compositions and methods of inhibiting angiogenesis in a mammal.
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- Synthesis and reactivity of α and β-chloro-α-phenylselanyl esters
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Thermal decomposition of the dichloro-adducts derived from α-phenylselanylesters 1, 2 and 4 has been studied. N-Chloro-succinimide treatment of esters 2 was an efficient preparative method for α-chloro-α-phenylselanylesters 10 and α-chloro-α,β-unsaturated esters 11. Some transformations of esters 10 were achieved, α,β-Dichloro-α-phenylselanylesters 22 were prepared from β-chloro-α-phenylselanylesters 5 or by decomposition of the dichloroselenuranes 21 derived from esters 4. (C) 2000 Elsevier Science Ltd.
- Lebarillier, Loic,Outurquin, Francis,Paulmier, Claude
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p. 7495 - 7502
(2007/10/03)
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- Preparation process for alpha , beta -dicarbonylated compounds
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Preparation process for alpha , beta -dicarbonylated compounds of formula (I) in which R2=alkyl, phenyl or benzyl being able to be substituted in various ways on the cycle, or carboxylic ester, and R3=alkyl or alkoxy or carboxylic ester in which a compound of formula (II) in which R1=alkyl, or alkyl alpha -ketocarboxylate or carboxylic ester, and R2 and R3 have the same meanings as previously is reacted in a nitrile type solvent, with molecular oxygen in the presence of copperII nitrate or ferric chloride as catalyst, and use for obtaining ethyl alpha -ketobutyrate, ethyl phenyl pyruvate, ethyl pyruvate, ethyl phenylglyoxylate, butane-2,3-dione or diethyl mesoxalate.
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- A convenient preparation of α-keto esters by the Grignard reaction on N-acylpyrazoles
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The α-keto esters were prepared by the formation of N-acylpyrazole followed by the appropriate Grignard reaction. These short step reaction conveniently afforded various α-keto esters in good yields.
- Kashima, Choji,Shirahata, Yoshie,Tsukamoto, Yoshihiro
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p. 459 - 464
(2007/10/03)
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- Synthesis and reactivity of β-phenylselanyl α-oxoesters
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β-Phenylsetanyl α-oxoesters 2 were prepared by N-phenylselanyl morpholine treatment of α-oxoesters 1, oxidized into β-unsaturated α- oxoesters 5 and subjected to the Wittig-Horner olefination. The diethyl (l- phenylselanylalkyl)maleates 6 have led, after [2,3]sigmatropic rearrangement of the corrsponding selenoxides to the diethyl 3-alkylidene-2- hydroxysuccinates 7. The 2-(1-butoxycarbonylamino)-3-alkylidenesuccinates 8 were prepared in a similar way. The decomposition of halo-adducts derived from components 6 has the synthesis of the siethyl 3-alkylidene-2- halosuccinates 9 and 10.
- Boivin, Stephane,Outurquin, Francis,Paulmier, Claude
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p. 16767 - 16782
(2007/10/03)
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- Process for the preparation of monocarbonyl or biscarbonyl compounds
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The invention relates to a process for the preparation of monocarbonyl or biscarbonyl compounds by reacting organic carbon compounds having one or more olefinic or aromatic double bonds in the molecule with the equivalent amount of ozone and by subsequently catalytically hydrogenating the ozonization products, wherein the peroxide-containing ozonization solution is fed continuously into a suspension of the hydrogenation catalyst in a lower aliphatic alcohol, while a peroxide content of not more than 0.1 mole/l is maintained, and the ozonization products are continuously cleaved reductively to give the corresponding carbonyl compounds.
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- Stereochemical Control on Yeast Reduction of α-Keto Esters. Reduction by Immobilized Bakers' Yeast in Hexane
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Ethyl 2-oxoheptanoate has been reduced by three methods: free bakers' yeast (FBY) in water, immobilized bakers' yeast (IMBY) in water, and IMBY in hexane.It has been found that the stereochemistry of reduction of α-keto esters by bakers' yeast is controlled by appropiate choice of reaction conditions.
- Nakamura, Kaoru,Inoue, Kiyoko,Ushio, Kazutoshi,Oka, Shinzaburo,Ohno, Atsuyoshi
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p. 2589 - 2593
(2007/10/02)
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- Reaction of α-Azido Esters with Lithium Ethoxide: Synthesis of Dehydroamino Esters and α-Keto Esters
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α-Azido esters 4 react with catalytic amounts of ethoxide in tetrahydrofuran/ethanol to evolve nitrogen and form dehydroamino esters 3.Acid hydrolysis gives α-keto esters 5 in good yields.
- Manis, Paul A.,Rathke, Michael W.
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p. 4952 - 4954
(2007/10/02)
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