Abstract: The present invention relates to a process for the preparation of Sevelamer carbonate from polyallylamine hydrochloride.

Abstract: The invention provides an improved process for preparing Ethacrynic acid of formula I, including the steps of: (a) reacting 4-butyryl-2,3-dichloro-phenoxy acetic acid of formula II with dimethylamine or its salt to obtain [2,3-dichloro-4-(2-dimethylaminomethylbutyryl)phenoxy] acetic acid of formula III or its salt; (b) hydrolyzing [2,3-dichloro-4-(2-dimethylaminomethylbutyryl)phenoxy] acetic acid hydrochloride of formula III obtained in step a) with t-butyl amine to obtain t-butyl amine salt of Ethacrynic acid; (c) acidifying the t-butyl amine salt of Ethacrynic acid formed in step b) to obtain Ethacrynic acid of formula I; and (d) optionally purifying the obtained Ethacrynic acid with a solvent mixture of alkyl acetate and hydrocarbon solvent. The invention also provides crystalline t-butylamine salt of Ethacrynic acid and process thereof. Also provide compound Ethacrynic acid having a purity of greater than or equal to 99% and a composition including the compound.

Abstract: Stable non-alcoholic transdermal hydrogel of dexibuprofen was prepared by using a simple manufacturing process, and the experimental trials showed that the pH modifying agent, antioxidant and water miscible solvent are the essential excipients to obtain stable non-alcoholic transdermal hydrogel of dexibuprofen. The dexibuprofen hydrogel prepared using carbopol as a gelling polymer produced an opaque gel, whereas hydrogel prepared using hyroxypropyl methylcellulose (HPMC) as a gelling polymer produced a transparent gel. There was no significant changes observed with respect to physical description, pH, assay and particularly to the related substance values when the hydrogels were subjected to the stability study at accelerated condition (40° C./75% RH) for 3 months in laminated tubes.

Abstract: The invention discloses a process for the preparation of Zileuton of formula I by employing acetic acid-1-benzo[b]thiophen-2-yl-ethyl-ester of formula-III as an intermediate.