[CH2:1]([N:8]1[C@H:12]([C:13]([O:15]CC)=[O:14])[CH2:11][CH2:10][C@@H:9]1[C:18]([O:20]CC)=[O:19])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C1CCC(C(NNCCC(NCC2C=CC=CC=2)=O)=O)CC1>Cl>[CH2:1]([N:8]1[C@H:9]([C:18]([OH:20])=[O:19])[CH2:10][CH2:11][C@@H:12]1[C:13]([OH:15])=[O:14])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1The first step in the preparation of this compound was to prepare diethyl cis-N-benzylpyrrolidine-2,5-dicarboxylate from diethyl meso-α,α'-dibromoadipate (see Example 1) as described by G. Cignarella and G. Nathansohn in J. Org. Chem., 26, p 1500, 1961. Diethyl cis-N-benzylpyrrolidine-2,5-dicarboxylate (103.5 g, 0.340 mole) was then heated in 1 liter concentrated hydrochloric acid at 100° C for 2 hours. Upon cooling, a crystalline solid precipitated. It was isolated by filtration, triturated with acetone-diethyl ether, and recrystallized from ethanol-water to give 41.3 g (49%) of partially hydrated product, melting point 254°-258° C. An infrared spectrum analysis gave λmax.Nujol = 2.95 μ (O--H).
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