Abstract: The present invention relates to a process of separation of 4-aza-androst-1-ene-17-oic acid from 4-aza-androstan-17-oic acid, which brings to 4-aza-androst-1-ene-17-oic containing less than 0.05% w/w of 4-aza-androstan-17-oic acid, with high yield and productivity. In particular, the present invention relates to a process for the separation of 4-aza-androstan-17-oic acid from 4-aza-androst-1-ene-17-oic acid, comprising the steps of treating the crude 4-aza-androst-1-ene-17-oic acid with formic acid and recovering the purified 4-aza-androst-1-ene-17-oic acid containing 4-aza-androstan-17-oic acid in w/w % less than 0.05%.
Abstract: The present invention relates to a process for the preparation of Brinzolamide, or 2H-thieno[3,2-e]-1,2-thiazin-6-sulfonamide, 4-(ethyl amino)-3,4-dihydro-2-(3-methoxypropyl)-, 1,1-dioxide, (4R)-via intermediates 2,3-dihydro-4H-thieno[3,2-e]-1,2-thiazin-4-ones, 1,1-dioxide. Further objects of the present invention are the intermediates mentioned above and other intermediates of the synthesis.
Type:
Grant
Filed:
June 15, 2009
Date of Patent:
January 1, 2013
Assignee:
PHF S.A.
Inventors:
Alessandro Falchi, Ottorino De Lucchi, Andrea Castellin
Abstract: The present invention relates to a process of separation of 4-aza-androst-1-ene-17-oic acid from 4-aza-androstan-17-oic acid, which brings to 4-aza-androst-1-ene-17-oic containing less than 0.05% w/w of 4-aza-androstan-17-oic acid, with high yield and productivity. In particular, the present invention relates to a process for the separation of 4-aza-androstan-17-oic acid from 4-aza-androst-1-ene-17-oic acid, comprising the steps of treating the crude 4-aza-androst-1-ene-17-oic acid with formic acid and recovering the purified 4-aza-androst-1-ene-17-oic acid containing 4-aza-androstan-17-oic acid in w/w % less than 0.05%.