成人免费xx,国产又黄又湿又刺激不卡网站,成人性视频app菠萝网站,色天天天天

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List Pramipexole Impurity 4
104632-25-9

Pramipexole Impurity 4 synthesis

13synthesis methods
-

Yield:104632-25-9 98%

Reaction Conditions:

with hydrogenchloride in water;acetone at 0 - 3; pH=1.5; for 2 h;Product distribution / selectivity;

Steps:

8

Example 8 (S)-2-Amino-6-(n-propyl)amino-4,5,6,7-tetrahydrobenzothiazole dihydrochloride monohydrate, (S)-pramipexole dihydrochloride monohydrate (I·2 HCl·1 H2O) A solution of (S)-pramipexole free base (Ia) (24.30 g) in acetone (730 ml) was cooled to 0-3°C, its pH was adjusted to 1.5 by the addition of 37% hydrochloric acid. The mixture was stirred at that temperature for 2 h and the precipitated crystals were collected by filtration. The cake was washed with cold acetone and air-dried to give 34.16 g (98%) product with m.p. 278-280°C. HPLC (purity, A%): 99.95%, [α]D20: -67.3 (c = 1.0, MeOH), optical purity (A%) (HPLC, using a chiral, optically active stationary phase): 99.6% ee.

References:

EP1878731,2008,A1 Location in patent:Page/Page column 11

Pramipexole Impurity 4 Related Search: