21245-02-3Relevant articles and documents
Flavonoid derivative
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, (2008/06/13)
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.
Nucleophilic acyl substitutions of esters with protic nucleophiles mediated by amphoteric, oxotitanium, and vanadyl species
Chen, Chien-Tien,Kuo, Jen-Huang,Ku, Cheng-Hsiu,Weng, Shiue-Shien,Liu, Cheng-Yuan
, p. 1328 - 1339 (2007/10/03)
(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.
Use of cyclic organic amines in dermatological compositions
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, (2008/06/13)
The use of cyclic organic amines, as free radicals deactivators, in the preparation of cosmetic and dermatological compositions.