[S:1]1[CH:5]=[CH:4][CH:3]=[C:2]1[CH2:6][CH2:7][CH2:8][N:9]1[CH2:13][CH2:12][C@@H:11]([O:14][C:15](=[O:28])[C:16]([OH:27])([C:22]2[S:23][CH:24]=[CH:25][CH:26]=2)[C:17]2[S:18][CH:19]=[CH:20][CH:21]=2)[CH2:10]1.C[Br:30].[CH3:31]COCC>C(#N)C.C(Cl)(Cl)Cl>[Br-:30].[OH:27][C:16]([C:22]1[S:23][CH:24]=[CH:25][CH:26]=1)([C:17]1[S:18][CH:19]=[CH:20][CH:21]=1)[C:15]([O:14][C@@H:11]1[CH2:12][CH2:13][N+:9]([CH3:31])([CH2:8][CH2:7][CH2:6][C:2]2[S:1][CH:5]=[CH:4][CH:3]=2)[CH2:10]1)=[O:28]0.3 g (0.00069 mol) of 2-Hydroxy-2,2-dithien-2-ylacetic acid (3R)-1-(3-thien-2-ylpropyl)pyrrolidin-3-yl ester (Intermediate 1-3) were dissolved in 4 ml of acetonitrile and 6 ml of CHCl3. To this solution 3.45 ml (0.00345 mol) of a 1 M solution of methyl bromide in acetonitrile were added. After stirring the mixture at room temperature under N2 atmosphere during 24 h, the solvents were evaporated. Ether was added to the residue and the mixture stirred to obtain a solid. This solid was treated with ether several times, filtered and washed with ether. The yield was 0.34 g (93.2%) of the title compound as a mixture of two stereoisomers.
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