Ampac Fine Chemicals LLC Patent applications |
Patent application number | Title | Published |
20150259289 | METHODS FOR PREPARING D-THREO METHYLPHENIDATE USING DIAZOMETHANE, AND COMPOSITIONS THEREOF - Novel methods and systems for producing a substantially pure d-threo stereoisomer of methylphenidate or a salt thereof are provided. In particular, methods and systems for producing d-threo-methylphenidate hydrochloride in pure stereoisomeric form from d-threo-ritalinic acid hydrochloride using diazomethane are described. The described methods can be performed on a large scale, and thus provide d-threo methylphenidate or a salt thereof, and particularly the hydrochloride salt of d-threo-methylphenidate, in stereoisomerically pure form and in large quantities from a single batch reaction. Also described are novel compositions of d-threo methylphenidate hydrochloride. | 09-17-2015 |
20150114315 | EVAPORATOR-FEEDER SYSTEM AND METHOD - A method for releasing an anhydrous gas in a gas phase at a target rate includes the step of obtaining a vessel at least partially filled with the anhydrous gas. The anhydrous gas is at least partially in a liquid phase and the vessel has an outlet for releasing the anhydrous gas in the gas phase. The method further includes releasing at least a portion of the anhydrous gas from the vessel through the outlet in the gas phase; applying a heat transfer fluid having a temperature of 32° F. to 150° F. to an exterior surface of the vessel during the releasing step, such that the anhydrous gas in the liquid phase is evaporated and the anhydrous gas in the gas phase is released at the target rate; and measuring starting and end weights of the vessel to monitor the releasing of the anhydrous gas in the gas phase. | 04-30-2015 |
20140051888 | NOVEL STEREOISOMERIC MIXTURES, SYNTHESIS AND USES THEREOF - A novel stereochemical mixture of 1,6-diaryl-2,5-diaminohexanes, such as a mixture of stereoisomers of 1,6-diphenylhexane-2,5-diamine, is described. Also described are methods of preparing stereochemically pure 1,6-diaryl-2,5-diaminohexanes, and particularly stereochemically pure 1,6-diphenyl-2,5-diaminohexane. Also described is the use of both the mixture of stereoisomers and the individual stereoisomers. | 02-20-2014 |
20100286444 | PREPARATION OF 2R,3S-N-ISOBUTYL-N-(2-HYDROXY-3-AMINO-4-PHENYLBUTYL)-P-NITROBENZENESULFON- YLAMIDE HYDROCHLORIDE AND OTHER DERIVATIVES OF 2-HYDROXY-1,3-DIAMINES - The present invention provides a new process for the preparation of 2R,3S-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride, wherein this compound is prepared directly from the chloromethylalcohol. Importantly, the process of the present invention results in higher yields of 2R,35-N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride without sacrificing its purity. The processes of the present invention can be used to prepare not only the 2R,3S-derivative, but also the 2S,3S-, 2S,2R- and the 2R,3R-derivatives. | 11-11-2010 |
20090292122 | PROCESS FOR THE PREPARATION OF CYANO-SUBSTITUTED-NITROGEN-CONTAINING HETEROARYL COMPOUNDS - The present invention provides compounds and methods that can be used to convert nitrogen-containing-heteroaryl carboxamides to the corresponding nitrogen-containing-heteroaryl nitriles reliably in one step, with high yields and without the need for elaborate purification. | 11-26-2009 |
20090242486 | SIMULATED MOVING BED CHROMATOGRAPHY FOR STRONGLY RETAINED COMPOUNDS - Simulated moving bed (SMB) chromatography involving a series of columns serially connected in a circuit is performed in a modified protocol by dividing the columns into two groups isolated from flow communication with each other and using one of the two groups solely for extraction of the more strongly retained component from the solid phase while the other group is operated in the conventional SMB manner. The sites of introduction and withdrawal and the site of division between the two groups of columns are all rotated around the circuit as in conventional SMB chromatography, but the process is capable of separating component mixtures with non-linear isotherms and of extracting solutes that are very strongly retained on the solid phase. | 10-01-2009 |
20080312469 | PREPARATION OF 2S,3S-N-ISOBUTYL-N-(2-HYDROXY-3-AMINO-4-PHENYLBUTYL)-P-NITROBENZENESULFONYLAMIDE HYDROCHLORIDE AND OTHER DERIVATIVES OF 2-HYDROXY-1,3-DIAMINES - The present invention provides a new process for the preparation of 2S,3S—N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride, wherein this compound is prepared directly from the chloromethylalcohol. Importantly, the process of the present invention results in higher yields of 2S,3S—N-isobutyl-N-(2-hydroxy-3-amino-4-phenylbutyl)-p-nitrobenzenesulfonylamide hydrochloride without sacrificing its purity. The processes of the present invention can be used to prepare not only the 2S,3S-derivative, but also the 2R,3S-, 2S,2R- and the 2R,3R-derivatives. | 12-18-2008 |
20080287704 | PREPARATIVE-SCALE SEPARATION OF ENANTIOMERS OF CHIRAL CARBOXYLIC ACIDS - High yields and purity are obtained in the purification of enantiomers of chiral carboxylic acids by preparative-scale chromatography by including a tertiary alcohol in the mobile phase in conjunction with an acidic modifier and a hydrophobic solvent. The tertiary alcohol is superior to other, more commonly used alcohols by reducing the extent of esterification of the enantiomer that otherwise lowers the yield and the purity. | 11-20-2008 |