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Nonconjugated Unsymmetrical Dienes
Published in George B. Butler, Cyclopolymerization and Cyclocopolymerization, 2020
Telomerization studies with allyl ethylsulfonate and allyl allylsulfonate have been carried out.168 Telomerization of allyl ethylsulfonate in the presence of butyl mercaptan yielded a mixture of a five-membered ring sultone containing a sulfide group and a five-membered ring sulfonium salt formed by reaction of the sultone with its own sulfide function. These results indicate that the cyclic units of poly(allyl ethylsulfonate) are five-membered rings. Telomerization of allyl allylsulfonate in the presence of butyl mercaptan yielded a mixture of two products formed by addition of butyl mercaptan to one of the two allyl functions. Telomerization of allyl allylsulfonate in BrCCl3 yielded a small amount of 1,1,1,5,5,5-hexachloro-3-bromo-pentane formed via fission of an O-C bond and a rearranged adduct. The rearrangement of the allyl group to a propenyl group in the case of allyl allylsulfonate was not observed when allyl ethylsulfonate or propyl allylsulfonate were telomerized under the same conditions. The rearrangement of the allyl double bond in allyl allylsulfonate is due to the presence of a second double bond in the same molecule. Poly (allyl allylsulfonate) might have a more complicated structure than expected from a simple cyclopolymerization mechanism.
Polysaccharides
Published in Stanislaw Penczek, H. R. Kricheldorf, A. Le Borgne, N. Spassky, T. Uryu, P. Klosinski, Models of Biopolymers by Ring-Opening Polymerization, 2018
46 is synthesized by ring closure of the SN2 type involving a hydroxyl group and a leaving group in a trans relation on C-3 and C-1 carbons, respectively, as shown in Scheme 5. 3-O-Allyl-d-glucopyranose is prepared by hydrolysis of 3-O-allyl-1,2:5,6-di-O-isopropylidene-α-d-glucofuranose in refluxing dilute sulfuric acid. Allyl alcohol containing hydrogen chloride is poured over 3-O-allyl-d-glucopyranose and heated to less than reflux temperature to give allyl 3-O-allyl-α,β-d-glucopyranoside (46a). Benzylation of 46a with powdered potassium hydroxide and benzyl chloride affords allyl 2,4,6-tri-O-benzyl-3-O-(`-propenyl)-α-d-glucopyranoside (46b), which is further reacted with potassium tert-butoxide to cause the isomerization of allyl group into 1-propenyl group, giving 1-propenyl 2,4,6-tri-O-benzyl-3-O-(1-propenyl)-α-d-glucopyranoside (46c). Crystalline 46c (3.05 g, 0.006 mol) is dissolved in 1,4-dioxane (20 ml), to which 1 M hydrochloric acid (1.5 ml) is added. The mixture is refluxed with stirring for 2 h. After ordinary treatment and drying to a syrup, the product (46d) is crystallized. Crude yield is 3.1 g (0.007 mol). The diol 46d (3.8 g, 0.008 mol) is reacted with hydrogen chloride to afford 2,4,6-tri-O-benzyl-α-d-glucopyranosyl chloride (46e) in about 100% yield.
Physical Constants of Organic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
4-(3-Hydroxy-1-propenyl)-2- Coniferyl alcohol methoxyphenol 2-Hydroxypropyl acrylate (2-Hydroxypropyl)trimethylammonium chloride 3-Hydroxy-1H-pyridin-2-one 1-Hydroxy-2,5-pyrrolidinedi- N-Hydroxysuccinimide one 4-Hydroxy-2-quinolinecarbox- Kynurenic acid ylic acid 8-Hydroxy-5-quinolinesulfonic acid 4-Hydroxy-2-quinolinone 2,4-Quinolinediol
Effect of natural antioxidants on oxidation stability of jackfruit seed oil (Artocarpus heterophyllus) biodiesel
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Nagarajan Jeyakumar, Bose Narayanasamy
The comparative analysis of the current research with earlier studies has been mentioned in Table 6. The compounds present in cumin species such as D-terpinene, cuminic aldehyde, p-cymene, beta-pinene, limonene, 1, 8 cineole are responsible for its antioxidant activity (Nadeem and Riaz 2012). The compounds present in coriander species such as BHA, Terpenoids, Flavanoids (Anthocyanin, tannins, lignins), hydroxyl groups and phenolics are responsible for the antioxidant activity (Bhat et al. 2014). The presence of compounds in garlic such as Alliin, Allyl Disulfides, Allicin, and Allyl cysteine are responsible for antioxidant activity. Allicin restrained the creation of superoxide, where allyl cysteine allyl disulfide and Alliin promotes scavenging of hydroxyl radicals (Chung 2006). The n-hexane fraction contains Trans-anethole, Anisyl aldehyde, Anisyl acetone and 4-(2-propenyl) – phenol is responsible for antioxidant activity of star anise (Yang et al. 2012). Monoterpenes such as 1,8 cineole, citronellyl acetate, 4-propyl guaiacol isoeugenol, flavonoids, and phenolics are responsible for antioxidant activity of Gooseberry (Ramadan, El-Ghorab, and Ghanem 2015).
Lung injury caused by occupational exposure to particles from the industrial combustion of cashew nut shells: a mice model
Published in Archives of Environmental & Occupational Health, 2021
D. S. Serra, R. S. Araujo, M. L. M. Oliveira, F. S. A. Cavalcante, J. H. Leal-Cardoso
Anethole (1-methoxy-4-propenyl-benzene, isoestragole) is an alkoxypropenylbenzene derivative and an important flavoring component of the essential oils of more than 20 plant species.8 Anethole is commonly used as a flavoring agent in the food, beverage, cosmetic and medical liquids industries. Worldwide, traditional uses of plants that contain anethole include mainly antioxidant,9–11 anti-inflammator,12 antithrombotic,13 anesthetic,14 healing,15 and anti-carcinogenic9 substances, as well as and relaxing agents with effect on aortic rings.16,17