Abstract: The invention provides methods of obtaining a peptide that include steps of synthesizing a peptide intermediate having one or more side chain protecting groups; providing a solvent to the peptide intermediate to form a peptide intermediate composition; and providing a precipitating agent in an amount sufficient to precipitate the peptide intermediate from the peptide intermediate composition, wherein the precipitating agent is an alcohol having three or more carbon atoms. Also provided are methods for precipitating peptides, methods for concentration peptides, and methods for filtering peptides.

Abstract: A seal for a flared end fitting, wherein the fitting includes a male portion having a tapered end, a female portion having a coordinated shape to the male portion, and a flow passage axially disposed in both female and male portions, the seal comprising: a frustoconical portion having an inner end and an outer end, wherein the inner end is circumferentially attached to one end of a cylindrical portion having two ends and coaxially disposed about the cylindrical portion, the cylindrical portion forms a flow passage through the seal, the frustoconical and cylindrical portions form a cavity that fits on the tapered end of the male portion of the fitting, and the cylindrical portion of the seal fits into the flow passage of the male portion of the fitting. A method of sealing a flared end fitting.

Abstract: The present invention relates to methods of reducing ketal acids, salts and esters to form corresponding ketal alcohols. More particularly, the reducing methods convert the ketal acids, salts, or esters to ketal alcohols by using a reducing agent that comprises a hydride that comprises one or more alkoxy moieties. The ketal alcohol is prepared in a hydrophobic reagent. This is purified by washing the hydrophobic reagent with one or more water washes. Because the ketal alcohol has some water solubility, the water washes are back-extracted with a hydrophobic solvent to recover additional ketal alcohol from such one or more water washes. The alcohol products are useful in many applications such as intermediates in the synthesis of pharmacologically important molecules.

Abstract: The present invention advantageously provides ketal functional compounds that can be strong electrophiles under conditions compatible with ketal groups, are stable, crystalline solids at room temperature, and are much safer to handle than ketal iodides. The present invention accomplishes by incorporating aromatic sulfonyl moieties into ketal functional materials. The compounds are useful starting materials or intermediates in the synthesis of more complex organic molecules.

Abstract: The present invention relates to methods of subjecting a mixture of stereoisomers to epimerization and optionally recrystallization procedures to obtain a desired stereoisomer in high yield and purity. Relying upon solubility differences, the epimerization desirably is carried out in a solvent mixture that extends the epimerization equilibrium in favor of the desired stereoisomer. Recrystallization from a solvent mixture upgrades the purity even more. Purified stereoisomers are useful in many applications such as intermediates in the synthesis of pharmacologically important molecules.

Abstract: The present invention relates to a novel process for producing a ?-lactone of the formula: using an acyl halide of the formula: wherein R1, R2 R3 and X are described herein, as well as novel intermediates. In particular, the present invention relates to a process for enantioselectively producing the (R)-?-lactone.

Abstract: The present invention relates to a novel process for producing a &dgr;-lactone of the formula: using an acyl halide of the formula: wherein R1, R2 R3 and X are described herein, as well as novel intermediates. In particular, the present invention relates to a process for enantioselectively producing the (R)-&dgr;-lactone.

Abstract: The present invention provides a method for preparing S-aryl cysteine. Specifically, the present invention provides enantioselective method for preparing S-aryl cysteine starting from cystine, cysteine or serine amino acid. The methods of the present invention provides S-aryl cysteine in enantiomeric excess of greater than about 96%.

Abstract: The present invention relates to a novel process for producing a &dgr;-lactone of the formula: using an acyl halide of the formula: wherein R1, R2 R3 and X are described herein, as well as novel intermediates. In particular, the present invention relates to a process for enantioselectively producing the (R)-&dgr;-lactone.

Abstract: The present invention relates to a novel process for producing a &dgr;-lactone of the formula: 1

Abstract: The present invention relates to a novel process for producing a &dgr;-lactone of the formula: 1

Abstract: The present invention relates to a novel process for producing a &dgr;-lactone of the formula: using an acyl halide of the formula: wherein R1, R2 R3 and X are described herein, as well as novel intermediates. In particular, the present invention relates to a process for enantioselectively producing the (R)-&dgr;-lactone.

Abstract: The present invention provides a method for preparing S-aryl cysteine. Specifically, the present invention provides enantioselective method for preparing S-aryl cysteine starting from cystine, cysteine or serine amino acid. The methods of the present invention provides S-aryl cysteine in enantiomeric excess of greater than about 96%.