Method of obtaining...

Details Method of obtaining... Method of obtaining...

2011-01-25

2011-01-25

Young, Shawquia (Department: 1626)

Organic compounds -- part of the class 532-570 series

Organic compounds

Amino nitrogen containing

Reexamination Certificate

active

07875750

ABSTRACT:
The present invention relates to a process for preparing 2-amino-6-alkyl-amino-4,5,6,7-tetrahydrobenzothiazoles (I) wherein the asterisk (*) represents an asymmetric carbon and R1is C1-C6alkyl; their enantiomers or mixtures thereof, their solvates, hydrates or pharmaceutically acceptable salts, comprising: (a) reacting a compound (II) with a secondary amine, optionally in the presence of an acid and a solvent 1, to form an enamine; (b) optionally removing said acid and said solvent 1, and then reacting said enamine with sulfur in the presence of a solvent 2; and (c) reacting the previously obtained compound with cyanamide to obtain the compound (I). Pramipexole, a compound with dopamine D-2 agonist activity, is among the compounds (I) and is useful for the treatment of Parkinson's disease and schizophrenia.

REFERENCES:
patent: 3682945 (1972-08-01), Engelhart
patent: 5708187 (1998-01-01), Flaugh et al.
patent: 6849290 (2005-02-01), Makinen et al.
patent: 7638542 (2009-12-01), Coca et al.
patent: 2005/0059717 (2005-03-01), van Eupen et al.
patent: 2006/0106224 (2006-05-01), Gupta et al.
patent: 0 186 087 (1986-07-01), None
patent: 0 027 696 (1987-01-01), None
patent: 0749962 (1996-12-01), None
Gewald, K., et al., “Sulfure-heterocyclics and precursors. XXX. A simple synthesis of 2-amino thiazoles”, “J. Prakt. Chem.”, 1964, pp. 298-300, vol. 23, No. 5-6.
Gewald, K., et al., “On the reaction of enamines with sulfur and cyanamide”, “J. Prakt. Chem.”, 1970, pp. 776-779, vol. 312, No. 5.
Merck & Co., Inc., “7705. Pramipexole”, “The Merck Index”, 2008, pp. 7707, Publisher: Merck Publishing.
European Medicines Agency, “Scientific Discussion: Approval of Mirapexin”, “Scientific Discussion”, Apr. 1, 2001, pp. 1-10, Publisher: European Medicines Agency.
Schneider, C. et al., “Dopamine Autoreceptor Agonists: Resolution and Pharmacological Activity of 2,6-Diaminotetrahydrobenzothiazole and a . . . ”, “J. Med. Chemistry”, 1987, pp. 494-498, vol. 30.
Vippagunta, S. et al., “Crystalline solids”, “Advanced Drug Delivery Reviews”, 2001, pp. 3-26, vol. 48.

Affiliated with

Also associated with

Rating

Method of obtaining... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of obtaining..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of obtaining... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2726447