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Total Synthesis of Some Important Natural Products from Brazilian Flora
Published in Luzia Valentina Modolo, Mary Ann Foglio, Brazilian Medicinal Plants, 2019
Leonardo da Silva Neto, Breno Germano de Freitas Oliveira, Wellington Alves de Barros, Rosemeire Brondi Alves, Adão Aparecido Sabino, Ângelo de Fátima
To synthesize different eusiderins, the authors traced a strategy involving a general route, varying only the reagent used in the last step responsible for the side chain and the substituents of the attached aromatic ring. The synthesis has two key steps: the first key step is a Mitsunobu reaction between the phenolic derived from the previously synthesized o-vanillin and (S)-ethyl lactate, thus fixing the first chiral center in the structure, followed by a reduction with DIBAL at −78°C that results in the formation of aldehyde 62 (Figure 12.16), a common intermediate for the other eusiderins, which undergoes an addition of an aromatic organometallic reagent that differentiates eusiderin A 58 from eusiderin B 59; after a reduction and cyclization in Amberlyst 15, formation of the intermediate occurs (63, 64), which undergoes the second key step of eusiderin synthesis (Suzuki reaction). Then, the eusiderins are synthesized from the intermediates 63 and 64, and the boronate ester side chain derived from organoboron is used, since the Suzuki reaction is a carbon-carbon cross-coupling reaction. A disadvantage faced in the synthetic route proposed by Pilkington and Barker (2012) is the step involving the formation of the second stereogenic center of the 1,4-benzodioxane ring, wherein the cyclization generates the cis and trans isomers in a ratio of 1:5, resulting in a reduction in the reaction yield due to the need to separate the products for the last step of the synthesis.
Natural Products and Stem Cells and Their Commercial Aspects in Cosmetics
Published in Heather A.E. Benson, Michael S. Roberts, Vânia Rodrigues Leite-Silva, Kenneth A. Walters, Cosmetic Formulation, 2019
Sonia Trehan, Rose Soskind, Jemima Moraes, Vinam Puri, Bozena Michniak-Kohn
Animal milk has been used for thousands of years as an ingredient of various cosmetic recipes and is still a source of proteins that are used in modern cosmetics. For example, Cleopatra bathed in milk to improve her skin appearance (Rajanala and Vashi, 2017). One such protein derived from milk is casein, which is rich in amino acids (Corbeil et al., 2000). Lactic acid is an α-hydroxy acid that is also derived from milk and is very common to find in cosmetic formulations. Lactic acid creates acidity and can be used in combination with its sodium salt, sodium lactate, to maintain the pH of cosmetic properties. Ethyl lactate may have an application in acne products by lowering the pH of sebaceous follicle ducts. Lactic acid can also be used as a humectant, which may improve skin smoothness and reduce photoaging, and can serve as an exfoliating agent in chemical peels (Smith, 1996).
Catalog of Herbs
Published in James A. Duke, Handbook of Medicinal Herbs, 2018
Per 100 g the fruit is reported to contain 47 to 52 calories, 85.3 to 87.0 g H2O, 0.4 to 0.7 g protein, 0.2 to 0.3 g fat, 11.6 to 13.7 g total carbohydrate, 0.4 to 0.5 g fiber, 0.3 to 0.4 g ash, 17 to 18 mg Ca, 8 to 12 mg P, 0.5 mg Fe, 1 to 2 mg Na, 125 to 146 mg K, 32 to 42 μg beta-carotene equivalent, 0.06 to 0.08 mg thiamine, 0.03 to 0.04 mg riboflavin, 0.2 to 0.3 mg niacin, and 17 to 61 (to 96) mg ascorbic acid.21 Cultivars may contain 1 to 5% citric acid (wild forms up to 8.6%), ca. 3.5% invert sugars, 7.5% saccharose, approaching 15% at maturity. Also reported are vanillin, methyl-n-propyl ketone, n-valerianic acid, isocapronic acid, acrylic acid, l( – )-malic acid, beta-methylthiopropionic acid methyl ester (and ethyl ester), 5-hydroxytryptamine, quinic acid-1,4-di-p-coumarin (my translation).33 The aromatics from the essential oils of the fruit include methanol, ethanol, n-propanol, isobutanol, n-pentanol, ethyl acetate, ethyl-n-butyrat, methylisovalerianate, methyl-n-capronate, methyl-n-caprylate, n-amyl-n-capronate, ethyl lactate, methyl-beta-methylthiolpropionate, ethyl-beta-methylthiolpropionate, and diacetyl, acetone, formaldehyde, acetaldehyde, furfurol, and 5-hydroxy-2-methylfurfurol.33 Steroid fractions of the lower leaves possess estrogenic activity.33
Green coffee nanoparticles: optimisation, in vitro bioactivity and bio-release property
Published in Journal of Microencapsulation, 2020
Nivas Manohar Desai, Joseph Gilbert Stanley, Pushpa S. Murthy
The green coffee (Robusta cherry) was decaffeinated using Ethyl lactate, a biodegradable, agrochemical, non-toxic solvent and the residual caffeine was 0.2 ± 0.01%. The defatted, decaffeinated samples were extracted with polar solvent and the physical characteristics such as yield, pH, moisture and water activity of the GCE is presented in Table 3. Green coffee extracted using water as solvent, chosen because of its high yield rate, cost effective, safety, and accessibility in comparision with the organic solvents. The nanoparticles were 34 µm in size, acidic (pH 5.8), with 6.2%±0.5 moisture and 0.42%±0.02 water activity. The colour measurement depicted GCE with light colour (L* 40.32, b* 21.33) screening greenish cyan. The GCE had 14.02 ± 2.3g/100g TPP, 41.48 ± 1.5g/100g chlorogenic acid with 414.8 ± 34.2 µmol Trolox/g RSA (ABTS) (Table 3). GCE enriched CGA was used for the production of nano particles.
Decontamination efficacy of soapy water and water washing following exposure of toxic chemicals on human skin
Published in Cutaneous and Ocular Toxicology, 2020
Emma Forsberg, Linda Öberg, Elisabet Artursson, Elisabeth Wigenstam, Anders Bucht, Lina Thors
Acrylonitrile was analyzed by liquid chromatography with ultraviolet/visible spectroscopy detection (LC-UV/VIS), 2-butoxyethanol and tributylamine by liquid chromatography with triple quadrupole mass spectrometry detection (LC-MS/MS). Ethyl lactate and methyl salicylate were analyzed by gas chromatography with flame ionization detection (GC–FID). The limit of quantification (LOQ) was determined to be the lowest calibrated level, i.e. 1 ppm, for all substances (Table 1).