- Flavonoid derivative
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The invention relates to a novel flavonoid derivative, to an extract comprising the flavonoid derivative, to the cosmetic and pharmaceutical use thereof, to preparations comprising the flavonoid derivative or extract, and to a process for the preparation of the flavonoid derivative or extract.
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- Nucleophilic Acyl Substitutions of Acids or Esters Catalyzed by Oxometallic Complexes, and the Applications in Fabricating Biodiesel
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The present invention discloses a method of nucleophilic acyl substitution (NAS) of carboxylic acids or esters (hereinafter acids/esters) catalyzed by oxometallic complexes. According to the mentioned method, NAS reactions between acids/esters (R1COOH/R1—COO—R2) and protic nucleophile (R3-AH) can be catalyzed by oxxmetallic complexes, wherein A stands for O, S, or NH. The general formula of the mentioned oxometallic complexes is MOmL1yL2z, wherein M is selected from IVB, VB, VIB or actinide groups, m, y, z are integers, and m, y≧1, z≧0. A general catalytic equation is shown as follows:
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- Nucleophilic acyl substitutions of esters with protic nucleophiles mediated by amphoteric, oxotitanium, and vanadyl species
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(Chemical Equation Presented) A diverse array of oxometallic species were examined as catalysts in nucleophilic acyl substitution (NAS) reactions of methyl (or ethyl) esters with protic nucleophiles. Among them, oxotitanium acetylacetonate (TiO(acac)2) and vanadyl chloride (VOCl 2-(THF)x) served as the most efficient and water-tolerant catalysts. Transesterifications of methyl and/or ethyl esters with functionalized (including acid- or base-sensitive) 1° and 2° alcohols can be carried out chemoselectively in refluxed toluene or xylene in a 1:1 substrate stoichiometry using 1 mol % catalyst loading. The resultant products were furnished in 85-100% yields by simple aqueous workup to remove water-soluble catalysts. The new NAS protocol is also amenable to amines and thiols in 74-91% yields, albeit with higher loading (2.5 equiv) of protic nucleophiles. Representative examples of commercial interests such as Padimate O and antioxidant additives for plastics were also examined to demonstrate their practical applications. A 1:1 adduct between TiO(acac)2 and a given 1-octadecanol was identified as (C18H37O) 2Ti(acac)2 and was responsible for its subsequent NAS of methyl esters.
- Chen, Chien-Tien,Kuo, Jen-Huang,Ku, Cheng-Hsiu,Weng, Shiue-Shien,Liu, Cheng-Yuan
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p. 1328 - 1339
(2007/10/03)
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- SUNSCREEN COMPOSITIONS
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The present invention relates to improved sunscreen compositions, more preferably to improved sunscreen compositions containing at least one sunscreening agent (sunscreen) and a silicone-polyamide copolymer.
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- Use of cyclic organic amines in dermatological compositions
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The use of cyclic organic amines, as free radicals deactivators, in the preparation of cosmetic and dermatological compositions.
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- Cosmetic screening composition containing a UV screen in combination with a polymer obtained by block polymerization in emulsion and its use for the protection of the human epidermis against ultraviolet radiations
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Cosmetic screening composition containing a UV screen in combination with a polymer obtained by block polymerization in emulsion and its use for the protection of the human epidermis against ultraviolet radiations.
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- Long-acting pyrethrum/pyrethroid based pesticides with silicone stabilizers
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Pesticidal compositions based on nontoxic, naturally unstable insecticides (pyrethrum, synthetic pyrethroids and mixtures thereof) include a liquid alkyl aryl silicone polymer which stabilizes the insecticide to provide an extended effective killing life. The compositions additionally include a synergist to provide an immediate killing action and an antioxidant to protect the insecticide against destruction by oxygen. Ultraviolet protectants and insect repellents may also be included. Applications include control of insect pests to animals and plants and general purpose insect control. Exemplary formulations are given for compositions to be applied as sprays, dips, powdered or dusts, foggers and shampoos.
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