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Synthesis, Spectroscopic and Crystal Structure Studies on Ethyl 5,7-Dimethyl Coumarin-4-Acetate  [PDF]
Kiran K. Pujar, G. N. Anilkumar, Manohar V. Kulkarni
Crystal Structure Theory and Applications (CSTA) , 2013, DOI: 10.4236/csta.2013.22012
Abstract:

Ethyl ester of 5,7-dimethyl coumarin-4-acetic acid has been synthesized from 3,5-Xylenol in a two step sequence of reaction involving Pechmann cyclisation and acid catalyzed esterification. The title compound 2 crystallizes in Monoclinic form, space group P 1 21/c 1, with a = 8.6248(4) ?, b = 18.9103(8) , c = 8.4204(4)?, β = 101.241(2）?, V = 1347.00(11) ?, D cal = 1.283 Mg/cm3, Z = 4. The molecule is stabilized by intermolecular C-H … O bonds.

Process for the Obtention of Coumaric Acid from Coumarin: Analysis of the Reaction Conditions  [PDF]
Néstor N. López-Castillo, Alma D. Rojas-Rodríguez, Brenda M. Porta, M. Javier Cruz-Gómez
Advances in Chemical Engineering and Science (ACES) , 2013, DOI: 10.4236/aces.2013.33025
Abstract:

Coumaric acid can be obtained from basic hydrolysis of coumarin, through a reaction process consisting on opening the lactone ring and cis-trans isomerization. Parameters such as reaction time, temperature, NaOH concentration, solvent and reaction atmosphere, have been thoroughly studied and analyzed, in order to determine the appropriate conditions for the maximum conversion efficiency of coumarin into coumaric acid. Experimental results show that the best conditions are a 1 hour reaction time, at 160℃, with a 20% sodium hydroxide aqueous solution, and in an inert reaction atmosphere.

乙酸-2-苯乙酯的合成途径与调节研究
A Study on the Synthetic Pathways and Regulation of Acetic Acid-2-phenyl Ethyl Ester
宋娟,张霁红,康三江,胡生海,李明泽
SONG Juan,ZHANG Ji-hong,KANG San-jiang,HU Sheng-hai,LI Ming-ze
- , 2018, DOI: 10.13718/j.cnki.xdzk.2018.08.004
Abstract: 为了研究苹果醋发酵过程中的特征性香气成分乙酸-2-苯乙酯的合成途径和调节，采用反应体系跟踪法检测各合成相关基质的浓度变化，发现在苹果醋发酵第7d后，乙酸-2-苯乙酯开始大量生成，第30 d达到最高值；根据分析乙酸-2-苯乙酯与其合成基质，AAT，Esterase酶活浓度之间的相关系数，初步确定乙酸-2-苯乙酯的合成途径同时存在酯酶途径和醇酰基转移酶途径，推测醇酰基转移酶途径可能是主要的合成途径，醇酰基转移酶可能是关键酶；通过外源加标法，检测到8 g/L是L-苯丙氨酸的最佳添加质量浓度，可以有效增加苹果醋的香气成分的生成量和醋酸质量浓度，进而提高苹果醋制品独特的香味和风味.研究结果为苹果醋制品香气成分和风味物质的深入研究和其关键工艺控制点提供了一定的参考依据.
In order to understand the synthetic pathway(s) and regulation of acetic acid-2-phenyl ethyl ester, which is a characteristic aroma component in apple vinegar fermentation, a preliminary study was made, in which the reaction system tracing method was adopted to detect the concentration change in the related synthetic matrices. The results showed that acetic acid-2-phenyl ethyl ester increased significantly after 7 days' fermentation and reached the highest after 30 days. According to the correlation coefficient between acetic acid-2-phenyl ethyl ester and its synthesis matrix, AAT and esterase activity, it was tentatively concluded that the esterase pathway and alcohol acyltransferase pathway existed simultaneously for the synthesis of acetic acid-2-phenyl ethyl ester, and it was speculated that the acyltransferase pathway could be the main synthetic pathway and acyltransferase could be the key enzyme. A test of the external standard method showed that 8 g/L was the optimal concentration of L-phenylalanine, which increased the aroma components of apple cider vinegar and the concentration of acetic acid, thus enhancing the unique scent and flavor of the apple vinegar products
苹果醋发酵过程中L-苯丙氨酸促进乙酸-2-苯乙酯的合成
宋娟
- , 2019, DOI: 10.13982/j.mfst.1673-9078.2019.1.009
Abstract: 为了初步研究食品添加剂L-苯丙氨酸对苹果醋发酵过程中的特征性香气成分乙酸-2-苯乙酯的合成途径及关键酶活的影响，采用HS-SPME-GC-MS和ELISA，检测各合成相关基质生成量和关键酶活性的变化。结果表明，不同添加量的L-苯丙氨酸有明显促进乙酸-2-苯乙酯及其相关合成基质生成量积累的作用，并且对ADH、AAT的酶活性也有一定的促进作用，而对Esterase酶活性有抑制作用。其中当L-苯丙氨酸添加量为8 g/L时，乙酸-2-苯乙酯生成量显著提高了43.76%~86.59%。因此，本试验初步将8 g/L作为L-苯丙氨酸的最佳添加量，初步推测L-苯丙氨酸通过醇酰基转移酶途径促进乙酸-2-苯乙酯的合成及其相关基质和关键酶活的生成量，赋予苹果醋产品更多独特的香气和风味，为生产工艺提供一定的参考依据。
In order to study the effects of L-phenylalanine (a food additive) on the synthetic pathway and key enzyme activity related to acetic acid-2-phenyl ethyl ester in apple vinegar fermentation, HS-SPME-GC-MS and ELISA were employed to detect the changes of the matrix concentration and key enzyme activities in the synthesis of acetic acid-2-phenyl ethyl ester. It was shown that different amounts of L-phenylalanine can significantly promote the production of acetic acid-2-phenyl ethyl ester and the synthesis of the related matrix, and L-phenylalanine can increase the enzymatic activities of ADH and AAT, however, it suppressed the activity of Esterase enzyme. When 8 g/L of L-phenylalanine was added, the concentration of acetic acid-2-phenyl ethyl ester significantly increased from 43.76% to 86.59%;Therefore, the optimum additive amount of L-phenylalanine was 8 g/L, speculating that L-phenylalanine induced the synthesis of acetic acid-2-phenyl ethyl ester and its related matrix, and increased key enzyme activities through alcohol acyltransferase pathway, which increased the unique aroma and flavor of apple vinegar products and provided a reference for the production process.
Ethyl Acetate (CAS No. 141 - 78 - 6) [Acetato de Etila (CAS No. 141 - 78 - 6)]
Eliza de Lucas Chazin
Revista Virtual de Química , 2012,
Abstract: thyl acetate (EtOAc) is a substance with many applications in the chemical industry, in analytical techniques and in organic synthesis laboratories as a solvent and reagent. This work presents the main methods currently used for the industrial synthesis of ethyl acetate. Some data about physical-chemical properties, applications and toxicity are also presented.
Synthesis of imidazol-1-yl-acetic acid hydrochloride: A key intermediate for zoledronic acid
Santosh Kumar Singh,Narendra Manne,Purna Chandra Ray,Manojit Pal
Beilstein Journal of Organic Chemistry , 2008, DOI: 10.3762/bjoc.4.42
Abstract: A convenient and practical synthesis of imidazol-1-yl-acetic acid hydrochloride was achieved via N-alkylation of imidazole using tert-butyl chloroacetate followed by a non-aqueous ester cleavage of the resulting imidazol-1-yl-acetic acid tert-butyl ester in the presence of titanium tetrachloride. The synthesized imidazol-1-yl-acetic acid hydrochloride was then utilized to prepare zoledronic acid.
IN VITRO ANTIOXIDANT ACTIVITY OF IPOEMA BILOBA
Priti Tagde,Farukh Khan,Bhushan Gandhare
International Journal of Phytopharmacy , 2012, DOI: 10.7439/ijpp.v1i2.248
Abstract: Biomolecules can be oxidized by free radicals. This oxidative damage has an important etiological role in aging and the development of diseases like cancer, atherosclerosis, and other inflammatory disorders. Synthetic antioxidants, like butylated hydroxyanisole, are good free radical scavengers; however, the synthetic antioxidants can be carcinogenic. Therefore, there is an increasing interest in searching for antioxidants of natural origin. Antioxidants with different chemical properties may recharge each other in an antioxidant network. The total antioxidant content of dietary plants may therefore be a useful tool for testing the 'antioxidant network' hypothesis. Several berries, fruits, nuts, seeds, vegetables, drinks and spices have been found to be high in total antioxidants. Initial studies in animals and humans are supportive as to the beneficial effects of dietary plants rich in total antioxidants. Additionally, antioxidants and other plant compounds may also improve the endogenous antioxidant defense through induction of antioxidant and phase 2 enzymes.1,2 Dietary plants rich in such compounds include broccoli, brussel sprouts, cabbage, kale, cauliflower, carrots, onions, tomatoes, spinach and garlic , antioxidants and other plant compounds may also improve the endogenous antioxidant defense through induction of antioxidant and phase 2 enzymes.
Fatty Acid-Derived Biofuels and Chemicals Production in Saccharomyces cerevisiae
Yongjin J. Zhou,Nicolaas A. Buijs,Verena Siewers,Jens Nielsen
Frontiers in Bioengineering and Biotechnology , 2014, DOI: 10.3389/fbioe.2014.00032
Abstract: Volatile energy costs and environmental concerns have spurred interest in the development of alternative, renewable, sustainable, and cost-effective energy resources. Environment-friendly processes involving microbes can be used to synthesize advanced biofuels. These fuels have the potential to replace fossil fuels in supporting high-power demanding machinery such as aircrafts and trucks. From an engineering perspective, the pathway for fatty acid biosynthesis is an attractive route for the production of advanced fuels such as fatty acid ethyl esters, fatty alcohols, and alkanes. The robustness and excellent accessibility to molecular genetics make the yeast Saccharomyces cerevisiae a suitable host for the purpose of bio-manufacturing. Recent advances in metabolic engineering, as well as systems and synthetic biology, have now provided the opportunity to engineer yeast metabolism for the production of fatty acid-derived fuels and chemicals.
高效液相色谱法测定栀子根中齐墩果酸3-乙酸酯含量
刘秀英,娄勇军,张伟娜,李红,杨欣,蒋孟良,金晓飞,钟丹
中国中医药信息杂志 , 2012,
Abstract: 目的 建立高效液相色谱法测定栀子根中齐墩果酸3-乙酸酯含量的方法。方法 样品采用不同种类、不同浓度、不同时间的酸水解,将栀子根中齐墩果酸3-乙酸酯水解成齐墩果酸后,用二氯甲烷萃取、蒸干、甲醇定容,制备供试液,再采用高效液相色谱法测定其含量。结果 样品的甲醇提取液加盐酸2 mL,加热回流4 h,水解较好。齐墩果酸3-乙酸酯在1.102 5～11.025 ?g范围内线性关系良好,r＝0.999 8,平均回收率为96.00%(RSD＝1.34%)。结论 本方法操作简便,重复性好,专属性强,可用于栀子根的质量控制
High performance thin layer chromatographic method for simultaneous estimation of ibuprofen and pseudoephedrine hydrochloride
Chitlange S,Sakarkar D,Wankhede S,Wadodkar S
Indian Journal of Pharmaceutical Sciences , 2008,
Abstract: High performance thin layer chromatographic method is developed for simultaneous estimation of ibuprofen and pseudoephedrine hydrochloride in tablets. Silica gel 60F 254 plates were used as stationary phase and t.butanol: ethyl acetate: glacial acetic acid: water (7:4:2:2 v/v) as mobile phase. Wavelength selected for analysis was 254 nm. Percent estimation of ibuprofen and pseudoephedrine hydrochloride was found to be 99.56% and 98.77%, respectively. Percent recovery for both the drugs was found in the range of 98.27% to 100.91%, respectively.
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