4707-47-5Relevant academic research and scientific papers
Two new glycosides from Dianella ensifolia (L.) DC
Fan, Miao-Yin,Liu, Bing-Rui,Yang, Fan,Zhang, Pu-Zhao
, p. 18 - 20 (2021/11/11)
The Dianella genus includes approximately 20 species in all over the world. So far, only the chemical constituents of the lipophilic extract from Dianella ensifolia have been investigated. However, there have been no reports of its aqueous extract. In thi
Method for catalytically synthesizing oak moss by supported solid base
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Paragraph 0040; 0045-0048; 0049; 0054; 0055, (2021/05/12)
The invention provides a method for catalytically synthesizing oak moss by using a supported solid base, which comprises the following steps of: preparing an important intermediate 4-hydroxy-3, 6-dimethyl-2-oxocyclohexane-3-methyl formate for synthesizing a main aroma component of the oak moss by using methyl propionylacetate and methyl crotonate as raw materials and using a supported solid base KF/gamma-Al2O3 as a catalyst, and finally, performing aromatization reaction to obtain a target product synthetic oak moss, namely 3, 6-dimethyl-beta-methyl resorcylate. The method solves the problem that sodium methoxide is difficult to recover. By utilizing the solid alkali KF/gamma-Al2O3, the efficient recovery and cyclic utilization of the catalyst are realized, the process cost is reduced, the secondary addition side reaction in the Michael reaction is inhibited, and the problem that the target product 3, 6-dimethyl-beta-methyl resorcylate is difficult to separate is solved.
Compositional variation of atranorin-related components of lichen Myelochroa leucotyliza dependent on extraction solvent and their quantitative analysis by qHNMR
Ojha, Manju,Kil, Yun-Seo,Youn, Ui Joung,Ok, Young Jun,Choi, Hyukjae,Nam, Joo-Won
, p. 1067 - 1073 (2021/04/05)
Introduction: Quantitative nuclear magnetic resonance (qNMR) is one of the effective and reliable quantification tools for natural product research. Myelochroa leucotyliza belongs to the genus Myelochroa, a common foliose lichen genus found in the Korean Peninsula, and has not been quantitatively analysed using NMR. Previous chemical studies on M. leucotyliza have been limited to the main components by traditional thin-layer chromatography (TLC) experiments. Objective: We explored the stability of atranorin, a major component of M. leucotyliza, in methanol and acetone using NMR and characterised the changes in the chemical profiles of the lichen extracts in methanol and acetone using qNMR. Methodology: Atranorin transformation in the presence of methanol was analysed using time-dependent proton (1H)-NMR analysis (600 MHz NMR spectrometer). A 1H qNMR (qHNMR) method was established using dimethyl sulfone as the internal standard for quantifying the selected components isolated from M. leucotyliza. Homogenous mixtures of the samples were dissolved in deuterated chloroform. Results: Time-dependent 1H-NMR experiments revealed that atranorin (5) from lichen M. leucotyliza decomposed into atraric acid (1) and methyl haemmatommate (2) in methanol. Four components were identified from M. leucotyliza: 1, 2, usnic acid (4), and 5, and their respective contents were determined using qHNMR. The percentages (w/w) of 1, 2, and 4 in the methanol extract were calculated as 5.66%, 0.69%, and 0.90%, while those of 1, 4, and 5 in the acetone extract were 1.70%, 1.68%, and 19.11%, respectively. Conclusion: We used qHNMR to effectively analyse quantitative compositional variations in two different M. leucotyliza extracts and reliably determined the chemical conversion of the unstable compound atranorin.
Method for synthesizing 2, 4-dihydroxy-3, 6-dimethyl methyl benzoate by using 4-O-demethylated barbatic acid
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Paragraph 0089; 0096-0098, (2020/05/30)
The invention provides a method for synthesizing 2,4-dihydroxy-3,6-dimethyl methyl benzoate (synthetic oak moss) by using 4-O-demethylated barbatic acid, and relates to the technical field of chemicalsynthesis. The technical scheme comprises: hydrolyzing 4-O-demethylated barbatic acid into 2,4-dihydroxy-3,6-dimethyl benzoic acid by adopting an acid hydrolysis or alkali hydrolysis method; carryingout a methyl esterification reaction with a methylation reagent by using 2,4-dihydroxy-3,6-dimethyl benzoic acid as a substrate; and treating after the reaction is finished so as to obtain 2,4-dihydroxy-3,6-dimethyl methyl benzoate (synthetic oak moss). According to the invention, the synthetic oak moss is synthesized by using the new intermediate through two-step synthesis, so that the synthesisprocess is simplified.
Method for aromatizing synthetic oak moss
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Paragraph 0021; 0023-0028, (2019/01/14)
The invention provides a method for aromatizing synthetic an oak moss. The method comprises the following steps: adding chlorinated 2,5dimethyl-dihydro-methyl resorcylate into a solvent acetonitrile for aromatization reaction; then carrying out cooling crystallization to obtain a coarse product of the synthetic oak moss. Compared with the prior art, the method for aromatizing the oak moss, disclosed by the invention, has the following advantages: firstly, the by-product sodium chloride produced by the reaction can be directly filtered; secondly, reactive water can be recycled; thirdly, when the aromatization reaction is carried out, the reaction is not drastic because the reaction occurs in the acetonitrile solvent, and the generated hydrogen chloride is easy to recover; fourthly, an aftertreatment process is simple and the purity of the produced crude product reaches 98 percent or above. Therefore, the method provides an improved process method for the synthetic oak moss, which is environmentally friendly and energy saving and can be used for industrial production.
Process for preparing perfume 2,5-dimethylmethyl resorcylate
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Paragraph 0013; 0041-0045, (2017/07/01)
The invention provides a method for synthesizing 2,5-dimethylmethyl resorcylate through a one-pot process. According to the method, four individual chemical reactions are integrated into a one-pot-process continuous reaction. According to the method, the industrial production of 2,5-dimethylmethyl resorcylate can be achieved by an economical, stable-process, high-product-quality and high-yield process.
First total synthesis of the antitumor antibiotic (±)-resorthiomycin
Ponde, Datta E.,Ramalingam,Patil, Mahesh L.,Borate, Hanumant B.,Deshpande, Vishnu H.
, p. 5399 - 5400 (2007/10/03)
The first total synthesis of (±)-resorthiomycin, an antitumor antibiotic has been achieved.
Depsides as non-redox inhibitors of leukotriene B4 biosynthesis and HaCaT cell growth. 1. Novel analogues of barbatic and diffractaic acid
Kumar, Sunil,Mueller, Klaus
, p. 1035 - 1042 (2007/10/03)
A series of barbatic and diffractaic acid analogues has been synthesized and evaluated as inhibitors of leukotriene B4 (LTB4) biosynthesis and as antiproliferative agents. The 4-O-demethyl barbatic and diffractaic acid derivatives were among the most active compounds in both assays. In particular, ethyl 4-O-demethylbarbatate was the most potent LTB4 biosynthesis inhibitor of this series, with an IC50 value in the submicromolar range. Because the compounds did not show appreciable reactivity against a stable free radical, 2,2-diphenyl-1-picrylhydrazyl, and did not produce appreciable amounts of deoxyribose degradation as a measure of their potency to generate hydroxyl radicals, a simple redox effect could not explain their biological activity. Also, there was no nonspecific cytotoxicity as documented by the activity of lactate dehydrogenase released from the cytoplasm of keratinocytes, which was in the control range.
Thermal Decomposition of Lichen Depsides
Huneck, Siegfried,Schmidt, Juergen,Tabacchi, Raffaele
, p. 1283 - 1289 (2007/10/02)
The thermal decomposition of the following lichen depsides has been described: lecanoric acid, gyrophoric acid, evernic acid, perlatolic acid, planaic acid, confluentic acid, atranorin, 4-O-demethylbarbatic acid, and sekikaic acid.Main reaction products are decarboxylated compounds, phenolic units, rearranged depsides, and xanthones.Triethylammonium salts of depside carboxylic acids decompose at reasonably lower temperature than the corresponding free acids. - Keywords: Lichen Depsides, Thermal Decomposition
Preparation of resorcinol derivatives
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, (2008/06/13)
A process for the preparation of resorcinol derivatives of the general formula I STR1 where R1 is carbalkoxy, nitrile, alkyl or H and R2 to R5 are H or lower alkyl, by reacting the corresponding cyclohexane-1,3-dione (II) with oxygen or an oxygen-containing gas in the presence of a catalytic amount of a copper compound and of from 1 to 10 moles of a hydrogen halide, or from 0.5 to 5 moles of thionyl chloride per mole of II, in an alkanol having from 1 to 6 carbon atoms, tetrahydrofuran or methyl tert.-butyl ether as the solvent, at from 0° to 150 C., without the addition of a significant amount of water to the reaction mixture. Some of the resorcinol derivatives prepared are useful scents with fragrance notes of the character of the odoriferous substance of natural oak moss.
