- Gas chromatography/electron-capture negative ion mass spectrometry for the quantitative determination of 2- and 3-hydroxy fatty acids in bovine milk fat
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2- and 3-hydroxy fatty acids (2- and 3-OH-FAs) are bioactive substances reported in sphingolipids and bacteria. Little is known of their occurrence in food. For this reason, a method suitable for the determination of OH-FAs at trace levels in bovine milk fat was developed. OH-FAs (and conventional fatty acids in samples) were converted into methyl esters and the hydroxyl group was derivatized with pentafluorobenzoyl (PFBO) chloride to give PFBO-O-FA methyl esters. These derivatives with strong electron affinity were determined by gas chromatography interfaced to mass spectrometry using electron-capture negative ion in the selected ion monitoring mode (GC/ECNI-MS-SIM). This method proved to be highly sensitive and selective for PFBO-O-FA methyl esters. For the analysis of samples, two internal standards were used. For this purpose, 9,10-dideutero-2-OH-18:0 methyl ester (ISTD-1) from 2-OH-18:1(9c) methyl ester as well as the ethyl ester of 3-PFBO-O-12:0 (ISTD-2) was synthesized. ISTD-1 served as a recovery standard whereas ISTD-2 was used for GC/MS measurements. The whole-sample cleanup consisted of accelerated solvent extraction of dry bovine milk, addition of ISTD 1, saponification, conversion of fatty acids into methyl esters by use of boron trifluoride, separation of the methyl esters of OH-FAs from nonsubstituted FAs on activated silica, conversion of OH-FAs methyl esters into PFBO-O-FA methyl esters, addition of ISTD-2, and measurement by GC/ECNI-MS-SIM. By this method, ten OH-FAs were quantified in bovine milk fat with high precision in the range from 0.02 ± 0.00 to 4.49 ± 0.29 mg/100 g of milk fat.
- Jenske, Ramona,Vetter, Walter
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experimental part
p. 5500 - 5505
(2010/03/25)
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- Sulfur-based amides and bis-amides useful against skin disorders
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Novel sulfhydryl group-containing amides and disulfide group-containing bis-amides useful for treating or preventing an abnormal biological condition or a disease, and/or improving the texture or appearance of the skin, as well as compositions containing amides and bis-amides and methods for their use are described. Such types of abnormal biological conditions or diseases include skin atrophy, i.e., the thinning and/or general degradation of the dermis often characterized by a decrease in collagen and/or elastin as well as decreased number, size and doubling potential of fibroblast cells, and other maladies including, but are not limited to dry skin, severe dry skin, dandruff, acne, keratoses, psoriasis, eczema, skin flakiness, pruritus, age spots, lentigines, melasmas, wrinkles, warts, blemished skin, hyperpigmented skin, hyperkeratotic skin, inflammatory dermatoses, age-related skin changes and skin in need of cleansers.
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- Synthesis of intermediates in the preparation of ACAT inhibitors
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This invention relates to novel processes for synthesizing intermediates in the preparation of N-aryl and N-heteroarylamide inhibitors of the enzyme acyl coenzyme A: cholesterol acyltransferase (ACAT), and to novel intermediates used in such processes.
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- A New and Facile Method for the Direct Preparation of α-Hydroxycarboxylic Acid Esters from α,β-Unsaturated Carboxylic Acid Esters with Molecular Oxygen and Phenylsilane Catalyzed by Bis(dipivaloylmethanato)manganese(II) Complex
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In the presence of a catalytic amount of bis(dipivaloylmethanato)manganese(II) complex, the oxygenation of benzyl crotonate with molecular oxygen and phenylsilane proceeds smoothly under a mild condition to give benzyl 2-hydroxybutyrate in high yield.The reaction provides a new and convenient method for the direct preparation of various α-hydroxycarboxylic acid esters starting from α,β-unsaturated carboxylic acid esters.The influence of substituents of olefins on regioselectivity is also studied.
- Inoki, Satoshi,Kato, Koji,Isayama, Shigeru,Mukaiyama, Teruaki
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p. 1869 - 1872
(2007/10/02)
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- Synthesis of S-Methyl 2-Hydrxyalkanethioates, 2-Hydroxyalkanoic Acids and Related Compounds via the Addition Reaction of Tris(methylthio)methanide Ion to Alkanals
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In connection with the studies on biological activities on myrmicacin and related compounds, the synthetic method for 2-hydroxyalkanoic acids and the corresponding 1,2-diols was studied.The addition reaction of tris(methylthio)methyllithium to the aldehydes (propanal-dodecanal) gave the corresponding 1,1,-tris(methylthio)-2-alkanols 1a-j.Treatment of 1 with mercury(II) chloride-mercury(II) oxide in water-acetone afforded S-methyl 2-hydroxyalkanethioates 2a-j, and in methanol methyl 2-hydroxyalkanoates 3c-j were obtained.Reduction of the thioates 2 with lithium aluminium hydride gave 1,2-diols 4c-j and saponification produced the corresponding 2-hydroxyalkanoic acids 5c-j.
- Orito, Kazuhiko,Seki, Yoshikatsu,Suginome, Hiroshi,Iwadare, Tsukasa
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p. 2013 - 2017
(2007/10/02)
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