摘要:
1-Benzyl(or substituted benzyl)-3.beta.-[4(S)-aryloxazolidin-2-one-3-yl]-4.beta.-(2-arylvinyl)azetidin-2-ones are provided via cycloaddition of a 4(S)-aryloxazolidin-2-one-3-ylacetyl halide and an imine formed with a benzylamine and a 3-arylacrolein, e.g. cinnamaldehyde. The azetidinones are useful chiral intermediates in an asymmetric synthesis of 1-carba(1-dethia)-3-hydroxy-3-cephem-4-carboxylic acids and esters and to monocyclic .beta.-lactam antibiotics.
摘要:
7.beta.-Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.
摘要:
A process for preparing a .beta.-keto ester of the formula ##STR1## is provided which comprises cycloaddition of an (S)-4-aryloxazolidin-2-one-3-ylacetyl halide with an imine formed with a benzyl amine and an m-alkoxycinnamaldehyde to form the azetidinone ##STR2## hydrogenation of the azetidinone to the 4-[2-(m-alkoxyphenyl)-ethyl]substituted azetidinone; reduction of the hydrogenation product with Li-NH.sub.3 and t-butyl alcohol to form the 3-aminoazetidinone. ##STR3## and N-acylation of the 3-aminoazetidinone followed by ozonolysis of the cyclodiene group; wherein, e.g. alk, is methyl, Ar is phenyl and R.sub.1 is phenoxymethyl.
摘要:
1-Benzyl (or substituted benzyl)-3.beta.-[4(S)-aryloxazolidin-2-one-3-yl]-4.beta.-(2-arylvinyl)azetidin-2-ones are provided via cycloaddition of a 4(S)-aryloxazolidin-2-one-3-ylacetyl halide and an imine formed with a benzylamine and a 3-arylacrolein, e.g. cinnamaldehyde. The azetidinones are useful chiral intermediates in an asymmetric synthesis of 1-carba(1-dethia)-3-hydroxy-3-cephem-4-carboxylic acids and esters and to monocyclic .beta.-lactam antibiotics.
摘要:
1-Benzyl(or substituted benzyl)-3.beta.-[4(S)-aryloxazolidin-2-one-3-yl]-4.beta.-(2-arylvinyl)azetidin-2-ones are provided via cycloaddition of a 4(S)-aryloxazolidin-2-one-3-ylacetyl halide and an imine formed with a benzylamine and a 3-arylacrolein, e.g. cinnamaldehyde. The azetidinones are useful chiral intermediates in an asymmetric synthesis of 1-carba(1-dethia)-3-hydroxy-3-cephem-4-carboxylic acids and esters and to monocyclic .beta.-lactam antibiotics.
摘要:
7.beta.-Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.
摘要:
7.beta.-Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.
摘要:
A human or animal dietary supplement composition comprising one or more long chain (C24-C36) primary alcohols (policosanols) dispersed in food-grade oils or fats where the policosanol particle size is substantially less than ten (10) microns. The composition (Nanocosanol™) is effective and convenient for supporting blood lipid health.
摘要:
A method of automatically constructing a model of an activity from an unsupervised examination of a plurality of textual documents describing the activity is comprised of: extracting prototypical steps from the plurality of textual documents; sequencing the extracted steps; aligning the sequenced steps; and constructing the model based on the aligned steps. The model may take the form of a step vs. position matrix which identifies the prototypical steps that make up the activity and provides the probability of each step occupying each position within the activity. The model thus constitutes common sense knowledge that encodes the stereotypical steps of an activity and the stereotypical sequencing of the steps.
摘要:
A packaged hybrid capacitor according to the invention includes a metal cup having a bottom wall with a periphery and an upstanding sidewall at the periphery and surrounding the bottom wall; a first capacitor electrode located within the sidewall and on the bottom wall of the metal cup; an endless electrically insulating plastic sealing member having a base and an outer wall upstanding from the base, disposed within the metal cup, the outer wall having a shape and size fitting within the cup, adjacent the sidewall of the cup; a metal cover including a top wall and a peripheral skirt extending from and surrounding the top wall and inclined relative the top wall toward an inside surface of the metal cover; a second capacitor electrode on the inside surface of the top wall; a separator disposed between the first and second electrodes; and an electrolyte within the capacitor and in contact with the first and second capacitor electrodes, wherein the sidewall of the metal cup bears against the peripheral skirt, with the outer wall of the sealing member interposed between the sidewall and the peripheral skirt, sealing the packaged hybrid capacitor and electrically insulating the metal cup from the metal cover. The sealing member preferably has a channel shape, in cross-section, including an inner wall opposite the outer wall that is captured between the skirt of the cover and the sidewall of the cup. The sealing member is preferably a plastic polymeric material such as polytetrafluoroethylene, polyethylene, polypropylene, silicone rubber, natural and synthetic rubbers, elastomers, polyvinyl chloride, and a moldable elastomer-polymer blend.