- POLYMORPHIC AND AMORPHOUS FORMS OF (R)-2-HYDROXY-2-METHYL-4-(2,4,5-TRIMETHYL-3,6-DIOXOCYCLOHEXA-1,4-DIENYL)BUTANAMIDE
-
Disclosed herein are polymorphic and amorphous forms of anhydrate, hydrate, and solvates of (R)-2-hydroxy-2-methyl-4-(2,4,5-trimethyl-3,6-dioxocyclohexa-1,4-dienyl)butanamide and methods of using such compositions for treating or suppressing oxidative stress disorders, including mitochondrial disorders, impaired energy processing disorders, neurodegenerative diseases and diseases of aging. Further disclosed are methods of making such polymorphic and amorphous forms.
- -
-
Paragraph 0191
(2016/07/05)
-
- Gold-catalyzed asymmetric allylic substitution of free alcohols: An enantioselective approach to chiral chromans with quaternary stereocenters for the synthesis of Vitamin E and analogues
-
The enantioselective synthesis of α- and γ-tocopherol (the most biologically active members of vitamin E family) and analogues has been accomplished employing a new enantioselective gold catalyzed intramolecular allylic alkylation reaction followed by an olefin cross-metathesis as key steps. The methodology proved to be applicable to different olefins highlighting its potential for the synthesis of diverse libraries. The enantioselective synthesis of α- and γ-tocopherol (the most biologically active members of vitamin E family) and analogues has been accomplished employing an enantioselective gold-catalyzed intramolecular allylic alkylation reaction followed by an olefin cross-metathesis as key steps (see scheme).
- Uria, Uxue,Vila, Carlos,Lin, Ming-Yuan,Rueping, Magnus
-
supporting information
p. 13913 - 13917
(2016/02/18)
-
- PROCESS FOR PRODUCTION OF OPTICALLY ACTIVE ORGANIC CARBOXYLIC ACID
-
The present invention is a simple method, in which a specific amount of alkali is added to an enantiomeric mixture of an optically active organic carboxylic acid where enantiomers are present in a non-equimolar ratio, or in which the enantiomeric mixture of an optically active organic carboxylic acid is neutralized with an alkali, and then a specific amount of acid is added thereto, thereby separating an organic carboxylic acid salt in the mother liquor and a crystallized organic carboxylic acid from each other. The method makes it possible to obtain an optically active organic carboxylic acid with improved enantiomeric excess. The present invention provides a simple production method for obtaining an optically active organic carboxylic acid with improved enantiomeric excess from an enantiomeric mixture of an optically active organic carboxylic acid where enantiomers are present in a non-equimolar ratio.
- -
-
Page/Page column 11
(2011/08/08)
-
- METHOD OF PRODUCING S-(-)-6-HYDROXY-2,5,7,8-TETRAMETHYLCHROMANE-2-CARBOXYLIC ACID AND PRODUCT OBTAINED BY THE METHOD
-
The present invention provides an industrially available method for efficiently producing high-purit y S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid excellent in solid-liquid separability from an S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid ester, and also provides products obtained by the method. Under a temperature condition of 50-80°C in an aqueous solvent, (A) an S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid ester represented by the general formula (1) is hydrolyzed under a basic condition for 1-3 hours; then (B) the insoluble matters contained in the reaction solution resulting from the hydrolysis are removed; and (C) an acid is added to the resulting solution to effect crystallization; provided that R in the general formula (1) represents an alkyl or aryl group.
- -
-
Page/Page column 8; 12
(2009/09/05)
-
- Perfluorobutylperoxyl Radical as an Oxidant in Various Solvents
-
Perfluorobutylperoxyl radicals were produced by pulse radiolysis of aerated solutions of perfluorobutyl iodide.The rate constants for reaction of this radical with several organic reductants, chlorpromazine, trolox, hydroquinone, and several other phenols, were determined in various solvents and were found to be in the range of 105 -109 M-1 s-1.By comparison with other haloalkylperoxyl radicals, C4F9OO. was found to be a much more powerful oxidant, whose reactions took place more rapidly and were less sensitive to solvent and substituent effects.The rate constants (k) for oxidation of a series of para-substituted phenols by C4F9OO. gave a good linear correlation between log k and the electrophilic substituent constant ?+, with a slope of ρ+ = -2.3, indicating formation of a positively charged transition state.Parallel experiments with CCl3OO. were limited to the most reactive phenols and gave a higher slope, ρ+ = -3.3.The rates of reaction of C4F9OO. with trolox and chlorpromazine were found to depend on solvent viscosity, but much less on solvent polarity and acid-base properties, probably because they were closer to the diffusion-controlled limit.The longer chain C10F21OO. was somewhat less reactive than C4F9OO. because of geometric factors.
- Nahor, G. S.,Neta, P.,Alfassi, Z. B.
-
p. 4419 - 4422
(2007/10/02)
-
- Total synthesis of naturally occurring α-tocopherol. Assymetric alkylation and asymmetric epoxidation as means to introduce (R)-configuration at C(2) of the chroman moiety
-
Based on the reductive, stereospecific ring closure of (2R,4'R,8'R)-α-'Tocopherylquinone' or corresponding analogues with a short, functionalized side chain (B, Scheme 1) to 1 resp. the chroman system of 1 (C), two different approaches for the introduction of the required tertiary methyl-substituted alcohol structure in the side chain of the aromatic precursors (A, Scheme 1) were developed. The first approach uses asymmetric alkylation in three different versions featuring a) diastereoselective steering with chiral auxiliaries I-IV (Scheme 2) attached as esters to α-keto acids, b) intermediate transfer of chirality in an ester enolate (from 18, Scheme 4) derived from an optically active α-hydroxyacid, c) enantioselective alkylation of phytenal (20) and subsequent ring closure with chirality transfer (Schemes 5-7). The second approach is based on the asymmetric epoxidation of β-metallylalcohol (Sharpless epoxidation), the corresponding epoxyalcohol being converted in situ to the (S)- or (R)-chlorodiol (S)- and (R)-29, respectively, for isolation (Schemes 8 and 9). Nucleophilic epoxide opening with a (3R,7R)-3,7,11-trimethyldodecyl (C15**) and an ArCH2 unit in appropriate sequence is used to assemble the C-framework of the target molecule via corresponding epoxide intermediates from either chlorodiol. Combined with the use of the methoxymethyl-ether function for protection of the hydroquinone system, the epoxide approach provides a short route to 1 (Scheme 10).
- Hubscher,Barner
-
p. 1068 - 1086
(2007/10/02)
-
- Novel Synthesis of (S)-(-)-Chroman-2-carboxylic Acid, Vitamin E Precursor
-
A new strategy to the synthesis of (S)-(-)-chroman-2-carboxylic acid, a pivotal intermediate possessing the absolute configuration required for the construction of α-tocopherol, was disclosed by utilizing asymmetric halolactonization of acylproline.Debromination followed by acidic hydrolysis directly afforded the title compound in 98percent enantiomer excess.
- Yoda, Hidemi,Takabe, Kunihiko
-
p. 465 - 466
(2007/10/02)
-
- Antioxidant chroman compounds
-
The (6-hydroxy-chroman-2-yl) acetic or carboxylic acid derivatives useful as antioxidants and a method for preparing these derivatives from hydroquinones and intermediates in this synthesis as well as the use of these derivatives as intermediates in the preparation of optically active alpha-tocopherol.
- -
-
-