- Synthesis and absolute configuration of 6-hydroxylated new ceramides in human skin, ceramides B, 4, 7 and 8
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6R-Configuration was assigned to three new ceramides isolated from human skin such as ceramide B [1, (2S,3R,4E,6R)-6-hydroxy-N-(30′- hydroxytriacontanoyl)-4-sphingenine], ceramide 8 [2, (2S,3R,4E,6R)-6-hydroxy-N- (tetracosanoyl)-4-sphingenine] and ceramide 4 {3, (2S,3R,4E,6R)-6-hydroxy-N- [(30′-linoleoyloxy)triacontanoyl]-4-sphingenine}. (6R,2′ R)-Configuration was given to another ceramide in human skin, ceramide 7 [4, (2S,3R,4E,6R,2′ R)-6-hydroxy-N-(2′-hydroxytetracosanoyl)-4- sphingenine]. These assignments were made possible by enzymatic preparation of the enantiomers of 1-pentadecyn-3-ol and those of 2-hydroxytetracosanoic acid. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
- Masuda, Yui,Mori, Kenji
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- Compositions and methods for enhancing the topical effects of sunscreen agents
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Uses of topical compositions comprising a 2-hydroxycarboxylic acid or related compound to alleviate or improve signs of skin, nail and hair changes associated with intrinsic or extrinsic aging are disclosed. 2-Hydroxycarboxylic acids and their related compounds include, for example, 2-hydroxyethanoic acid, 2-hydroxypropanoic acid, 2-methyl 2-hydroxypropanoic acid, 2-phenyl 2-hydroxyethanoic acid, 2-phenyl 2-methyl 2-hydroxyethanoic acid, 2-phenyl 3-hydroxypropanoic acid, 2,2-diphenyl 2-hydroxyethanoic acid, 2-hydroxybutane-1,4-dioicacid, 2,3-hihydroxybutane-1,4-dioic acid, 2-carboxy 2-hydroxypentane-1,5-dioic acid, 2-ketopropanoic acid, methyl 2-ketopropanoate, ethyl 2-ketopropanoate, and gluconolactone. Topical application of compositions comprising 2-hydroxycarboxylic acid and/or related compounds has been found to alleviate or improve skin lines; blotches; blemishes; nodules; wrinkles; pigmented spots; atrophy; precancerous lesions; elastotic changes characterized by leathery, coarse, rough, dry and yellowish skin; and other skin changes associated with intrinsic aging or skin damages caused by extrinsic factors such as sunlight, radiations, air pollution, wind, cold, dampness, heat, chemicals, smoke and cigarette smoking. Topical applications of such compositions have also been found to improve the overall qualities of nail and hair affected by intrinsic aging or damaged by extrinsic factors.
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- Selective N-acylation of amino alcohols
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The present invention provides an efficient method for the production of N-acyl amino alcohols via the selective acylation of the free amines of amino alcohols by reacting with an organic acid or a salt thereof with an alkyl sulfonyl chloride or an alkyl phenyl sulfonyl chloride, in an organic solvent and in the presence of an organic base, to form the corresponding mixed anhydride, followed by reacting the mixed anhydride with an amino alcohol or a salt thereof to form the corresponding N-acyl amino alcohol.
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