• 제목/요약/키워드: propionate

검색결과 519건 처리시간 0.032초

Total Synthesis of a Demethoxy-egonol from Styrax obassia

  • Choi, Hong-Dae;Ha, Mun-Choun;Seo, Pil-Ja;Son, Byeng-Wha;Song, Jin-Cherl
    • Archives of Pharmacal Research
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    • 제23권5호
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    • pp.438-440
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    • 2000
  • The total synthesis of a demethoxy-egonol isolated from Styrax obassia, 5-(3-hydroxypropyl)-2-(3',4'-methylenedioxyphenyl)benzofuran (9), is described. The key steps involve the construction of a 2-arylbenzofuran skeleton 7 from methyl 3-(4-hydroxyphenyl)propionate with 2-chloro-2-methylthio-(3',4'-methylenedioxy) acetophenone (6) in the presence of ZnCl$_2$ and successive desulfurization of the resulting product 7.

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Synthesis of Hexaprofen [2-(4-Cyclohexylphenyl) propionic Acid]

  • Choi, Hong-Dae;Ma, Jung-Joo;Son, Byeng-Wha
    • Archives of Pharmacal Research
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    • 제15권2호
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    • pp.142-145
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    • 1992
  • A novel preparative method for hexaprofen, which is a potent antiinflammatory agent, is described. Friedel-Crafts reaction of cyclohexylbenzene with ethyl $\alpha$-chloro-$\alpha$-(methylthio) acetate 1 and $\alpha$-chloro-$\alpha$-(methylthio) acetonitrile 2 afforded ethyl 2-(methylthio)-2-(4-cyclohexylphenyl) acetate 7 and 2-methylthio-2-(4-cyclohexylphenyl) acetonitrile 8, respectively. Compounds 7 and 8 were converted into the corresponding ethyl 2-methylthio-2-(4-cyclohexylphenyl) propionate 9 and 2-methylthio-2-(4-cyclohexylphenyl) propionitrile 10 by methylation with sodium hydride and methyl iodide. Hexaprofen 13 was prepard by hydrolysis of ethyl 2-(4-cyclohexylphenyl) propionate 11 and of 2-(4-cyclohexylphenyl) propionitrile 12 followed by desulfurization of compounds 9 and 10.

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PM3 Studies on the Acid-Catalyzed Hydrolysis of 1-Phenoxyethyl Propionate

  • 김찬경;이인영;정동수;이본수;이익춘
    • Bulletin of the Korean Chemical Society
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    • 제19권9호
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    • pp.993-999
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    • 1998
  • Acid catalyzed hydrolysis of 1-phenoxyethyl propionate, Ⅰ, has been studied using the PM3 method in the gas phase. The first step of the reaction is the protonation of basic sites, three different oxygens in Ⅰ, producing three protonated species Ⅱ, Ⅲ and Ⅳ. All possible reaction pathways have been studied from each protonated structure. Changes in the reaction mechanisms have also been discussed from the results obtained by varying a nucleophile from a water monomer to a water dimer to a complex between one water molecule and an intermediate product (propionic acid or phenol) produced in the preceding unimolecular dissociation processes. Minimum energy reaction pathway is 2-W among the possible pathways, in which water dimer acts as an active catalyst and therefore facilitates the formation of a six-membered cyclic transition state. Lower barrier of 2-W is ascribed to an efficient bifunctional catalytic effect of water molecules. PM3-SM3.1 single point calculations have been done at the gas-phase optimized structure (SM3.1/PM3//PM3) to compare theoretical results to those of experimental work.

항염증제로서 2-아릴-5-벤즈옥사졸프로피온산 유도체의 합성 (Synthesis of 2-Aryl-5-benzoxazolepropionic Acid Derivatives as Antiinflammatory Agent)

  • 최홍대;곽용실;금덕현;손병화
    • 약학회지
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    • 제38권5호
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    • pp.504-510
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    • 1994
  • A facile synthesis of 2-aryl-5-benzoxazolepropionic acid derivatives(1 0a-d), which are potent antiinflammatory agent, is reported. Methyl ${\alpha}$-(p-hydroxyphenyl)propionate(5) was prepared from Friedel-Crafts reaction of isopropoxy benzene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio) acetate(1), followed by desulfurization, methylation and clevage of ether bond. Compounds(10a-d) were made from(5) by a sequence of nitration, reduction, formation of benzoxazole ring, and hydrolysis in good yields, respectively.

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Effects of calcium propionate on the fermentation quality and aerobic stability of alfalfa silage

  • Dong, Zhihao;Yuan, Xianjun;Wen, Aiyou;Desta, Seare T.;Shao, Tao
    • Asian-Australasian Journal of Animal Sciences
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    • 제30권9호
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    • pp.1278-1284
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    • 2017
  • Objective: To assess the potency of calcium propionate (CAP) used as silage additive, an experiment was carried out to evaluate the effect of CAP on the nitrogen transformation, fermentation quality and aerobic stability of alfalfa silages. Methods: Alfalfa was ensiled with four levels of CAP (5, 10, 15, and 20 g/kg of fresh weight [FW]) in laboratory silos for 30 days. After opening, the silages were analyzed for the chemical and microbiological characteristics, and subjected to an aerobic stability test. Results: The increasing proportion of CAP did not affect pH, lactic acid (LA) concentrations and yeast counts, while linearly decreased counts of enterobacteria (p = 0.029), molds (p<0.001) and clostridia (p<0.001), and concentrations of acetic acid (p<0.001), propionic acid (p<0.001), butyric acid (p<0.001), and ethanol (p = 0.007), and quadratically (p = 0.001) increased lactic acid bacteria counts. With increasing the proportion of CAP, the dry matter (DM) loss (p<0.001), free amino acid N (p<0.001), ammonia N (p = 0.004), and non-protein N (p<0.001) contents were linearly reduced, whereas DM (p = 0.048), water soluble carbohydrate (p<0.001) and peptide N (p<0.001) contents were linearly increased. The highest Flieg's point was found in CAP10 (75.9), represented the best fermentation quality. All silages treated with CAP improved aerobic stability as indicated by increased stable hours compared with control. Conclusion: The addition of CAP can suppress the undesirable microorganisms during ensiling and exposure to air, thereby improving the fermentation quality and aerobic stability as well as retarding the proteolysis of alfalfa silage. It is suggested that CAP used as an additive is recommended at a level of 10 g/kg FW.

기관지 과민성이 동반된 중증 만성 폐쇄성 폐질환 환자에 대한 Salmeterol/Fluticasone Propionate와 Tiotropium Bromide 병합 요법과 단독 요법 치료효과 비교 (Comparison for the Effects of Triple Therapy with Salmeterol/Fluticasone Propionate and Tiotropium Bromide versus Individual Components in Patients of Severe COPD Combined with Bronchial Hyperresponsiveness)

  • 손지연;김소리;박성주;이흥범;이용철;이양근
    • Tuberculosis and Respiratory Diseases
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    • 제67권6호
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    • pp.536-544
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    • 2009
  • Background: A combination of salmeterol and fluticasone propionate (SFC) and tiotropium bromide (TIO) is commonly prescribed for COPD patients but there is little data on their effectiveness, particularly in COPD patients with bronchial hyperresponsiveness. This study compared the spirometric improvement based on the change in $FEV_1$, $FEV_1$/FVC, and IC as well as the clinical outcomes of the therapeutic strategies with SFC and TIO versus the individual components in patients with severe COPD and bronchial hyperresponsiveness. Methods: This study examined the spirometric data and clinical outcomes of 214 patients with COPD and hyperresponsiveness, who were divided into three groups according to the therapeutic regimen (TIO only, SFC only, and a triple therapy regimen). Results: All regimen groups showed early improvement in the $FEV_1$ and IC (at 3- and 6 months after treatment). However, long-term beneficial effects were observed only in the SFC group (at 24 months after treatment). However, these beneficial effects decreased after a 36-month follow up. In all spirometric results, the 12-, 24-, and 36-months data showed a similar degree of improvement in the three groups. The triple therapy group showed higher St. George's Respiratory Questionnaire scores and lower acute exacerbations and hospitalization. Conclusion: SFC can be a more important component in the pharmacological treatment of severe COPD patients with hyperresponsiveness than TIO, particularly in the spirometric and clinical outcomes.

Dietary rambutan peel powder as a rumen modifier in beef cattle

  • Ampapon, Thiwakorn;Wanapat, Metha
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권5호
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    • pp.763-769
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    • 2020
  • Objective: The experiment was conducted to study the effect of rambutan (Nephelium lappaceum) fruit peel powder (RP) on feed consumption, digestibility of nutrients, ruminal fermentation dynamics and microbial population in Thai breed cattle. Methods: Four, 2-year old (250±15 kg) beef bull crossbreds (75% Brahman×25% local breed) were allotted to experimental treatments using a 4×4 Latin square design. Four dietary supplementation treatments were imposed; non-supplementation (control, T1); supplementation of RP fed at 2% of dry matter intake (DMI) (low, T2); supplementation of RP fed at 4% of DMI (medium, T3) and supplementation of RP fed at 6% of DMI (high, T4). All cattle were given a concentrate supplement at 1% of body weight while Napier grass was provided as a free choice. Results: The findings revealed that RP supplementation did not negatively affect (p>0.05) DMI of Napier grass, while RP intake and total DMI were the greatest in the RP supplementation at 4% and 6% DMI. Nevertheless, the nutrients (dry matter, organic matter, crude protein, neutral detergent fiber, and acid detergent fiber) digestibilities were not changed in the RP supplementation groups. Rumen fermentation parameters especially those of total volatile fatty acids, acetate and butyrate were not significantly changed. However, the propionate concentration was remarkably increased (p<0.05) in the RP supplementation. Notably, the ratio of acetate to propionate, the number of protozoa, as well as the methane estimation were significantly reduced in the RP supplemented groups (4% and 6% of DMI), while the counts of bacteria was not altered. Conclusion: Supplementation of RP (4% of DMI) improved rumen propionate production, reduced protozoal population and methane estimation (p<0.05) without a negative effect on feed consumption and nutrients total tract digestibilities in beef cattle. Using dietary rambutan fruit peel powder has potential promise as a rumen regulator.

Effect of Different Biosynthetic Precursors on the Production of Nargenicin $A_1$ from Metabolically Engineered Nocardia sp. CS682

  • Koju, Dinesh;Maharjan, Sushila;Dhakal, Dipesh;Yoo, Jin Cheol;Sohng, Jae Kyung
    • Journal of Microbiology and Biotechnology
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    • 제22권8호
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    • pp.1127-1132
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    • 2012
  • Nargenicin $A_1$ is a 28-membered polyketide macrolide, with antibacterial activity against methicillin-resistant Staphylococcus aureus, produced by Nocardia sp. CS682. In this study, the production of nargenicin $A_1$ was improved by enhancing the supply of different biosynthetic precursors. In Nocardia sp. CS682 (KCTC11297BP), this improvement was ~4.62-fold with the supplementation of 30 mM methyl oleate, 4.25-fold with supplementation of 15mM sodium propionate, and 2.81-fold with supplementation of 15 mM sodium acetate. In Nocardia sp. metK18 and Nocardia sp. CS682 expressing S-adenosylmethionine synthetase (MetK), the production of nargenicin $A_1$ was improved by ~5.57-fold by supplementation with 30 mM methyl oleate, 5.01-fold by supplementation with 15 mM sodium propionate, and 3.64-fold by supplementation with 15 mM sodium acetate. Furthermore, supplementing the culture broth of Nocardia sp. ACC18 and Nocardia sp. CS682 expressing the acetyl-CoA carboxylase complex (AccA2 and AccBE) with 30 mM methyl oleate, 15 mM sodium propionate, or 15 mM sodium acetate resulted in ~6.99-, 6.46-, and 5.58-fold increases, respectively, in nargenicin $A_1$ production. Our overall results showed that among the supplements, methyl oleate was the most effective precursor supporting the highest titers of nargenicin $A_1$ in Nocardia sp. CS682, Nocardia sp. metK18, and Nocardia sp. ACC18.