Details for Patent: 9,499,546

Title:	Process for the preparation of chiral 8-(3-aminopiperidin-1-yl)-xanthines
Abstract:	The invention relates to an improved process for preparing enantiomerically pure 8-(3-aminopiperidin-1-yl)-xanthines.
Inventor(s):	Pfrengle; Waldemar (Biberach an der Riss, DE), Pachur; Thorsten (Biberach an der Riss, DE), Nicola; Thomas (Ingelheim am Rhein, DE), Duran; Adil (Biberach an der Riss, DE)
Assignee:	Boehringer Ingelheim International GmbH (Ingelheim am Rhein, DE)
Filing Date:	Oct 06, 2014
Application Number:	14/507,190
Claims:	1. A process for preparing a medicament comprising a first compound of formula ##STR00015## or a physiologically acceptable salt thereof, the process comprising deprotecting a second compound of formula ##STR00016## by detaching the phthalyl protecting group to provide the first compound, wherein R.sup.1 is a (4-methylquinazolin-2-yl)methyl, (3-methylisoquinolin-1-yl)methyl or (3-cyanopyridin-2-yl)methyl group, R.sup.2 is a methyl group, and R.sup.3 is a 2-butyn-1-yl group; and combining the first compound with one or more inert carriers and/or diluents. 2. The process according to claim 1 wherein R.sup.1 is a (4-methylquinazolin-2-yl)methyl. 3. The process according to claim 2, wherein the phthalyl protecting group of the second compound is detached in the presence of ethanolamine. 4. The process according to claim 2, wherein the phthalyl protecting group of the second compound is detached in the presence of (a) ethanolamine and toluene or (b) ethanolamine and a mixture of tetrahydrofuran and water. 5. The process according to claim 2, further comprising crystallizing the first compound from ethanol or methanol. 6. The process according to claim 2, further comprising crystallizing the first compound from ethanol. 7. The process according to claim 2, wherein the step of detaching the phthalyl protecting group of the second compound is carried out the presence of (a) ethanolamine and toluene or (b) ethanolamine and a mixture of tetrahydrofuran and water, to provide the first compound, and the process further comprises crystallizing the first compound from ethanol or methanol. 8. The process according to claim 7, wherein the first compound is crystallized from ethanol.