| DONGWOO SYNTECH CO., LTD Patent applications |
| Patent application number | Title | Published |
| 20110040097 | PROCESS FOR PREPARING LERCANIDIPINE HYDROCHLORIDE - Disclosed herein is a novel method for preparing lercanidipine hydrochloride which is highly effective for treating hypertension. The method comprises the steps of reacting 2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid with a substituted chlorophosphate derivative to obtain a substituted phosphonoester derivative, and reacting the substituted phosphonoester derivative with 2, N-dimethyl-N-(3,3-diphenylpropyl)-1-amino-2-propanol. According to the preparation method, since little by-products are formed, the yield is improved, as compared to cases of conventional methods. In addition, the method involves simple isolation and purification processes of lercanidipine, thus realizing a high-quality product. Furthermore, the method has advantages of low preparation costs, substantial waste-free environmental-friendly process and applicability to industrial mass-production. | 02-17-2011 |
| 20100120803 | 3,4-DIHYDROQUINAZOLINE DERIVATIVES - The present invention relates to 3,4-dihydroquinazoline derivatives, a process of preparing them and a pharmaceutical composition including them. The 3,4-dihydroquinazoline derivatives of the present invention have excellent T-type calcium channel blocking effect and anti-cancer activity. | 05-13-2010 |
| 20100069625 | PROCESS FOR PREPARING OF 2'-DEOXY-2'2'-DIFLUOROCYTIDINE - Disclosed is a method for preparing 2′-deoxy-2′,2′-difluorocytidine of Formula I comprising, preparing an optically pure 3R-hydroxypropane amide compound of Formula VIII from an optical ester compound of Formula IX using an optically active chiral amine, preparing an optically pure D-erythro-2,2-difluoro-2-deoxy-1-oxoribose compound of Formula V from the compound of Formula VIII, glycosylating the compound of Formula V with a nucleobase to prepare the 2′-deoxy-2′,2′-difluorocytidine of Formula I as a β-nucleoside. With the present invention, it is possible to prepare an optically pure compound of Formula I in a high purity and a high yield. In the Formulae, R | 03-18-2010 |
| 20100016592 | PROCESS FOR PREPARING SODIUM RISEDRONATE HEMIPENTAHYDRATE - A novel process for preparing risedronate sodium hemipentahydrate represented by the following formula 1 using 2-(3-pyridyl)-1-hydroxyethane-1,1-bisphosphonic acid (risedronic acid) and an aqueous solution of risedronate sodium is disclosed. | 01-21-2010 |