[C:1]([O:5][C:6]([NH:8][CH2:9][CH2:10][CH2:11][CH2:12][C@@H:13]([C:15]([OH:17])=[O:16])[NH2:14])=[O:7])([CH3:4])([CH3:3])[CH3:2].C([N+](CC)(CC)CC)C1C=CC=CC=1.[N+](C1C=CC([O:41][C:42](=O)[C@H:43]([CH2:55][C:56](=[O:58])[NH2:57])[NH:44][C:45]([O:47][CH2:48][C:49]2[CH:54]=[CH:53][CH:52]=[CH:51][CH:50]=2)=[O:46])=CC=1)([O-])=O.N1C=CC=CC=1>CN(C)C=O>[CH2:48]([O:47][C:45]([NH:44][C@H:43]([C:42]([NH:14][C@H:13]([C:15]([OH:17])=[O:16])[CH2:12][CH2:11][CH2:10][CH2:9][NH:8][C:6]([O:5][C:1]([CH3:4])([CH3:2])[CH3:3])=[O:7])=[O:41])[CH2:55][C:56](=[O:58])[NH2:57])=[O:46])[C:49]1[CH:50]=[CH:51][CH:52]=[CH:53][CH:54]=151 g Nε-tert.butyloxycarbonyl-L-lysine were converted in a conventional manner into the benzyltriethylammonium salt and then stirred in 700 ml dimethylformamide with 81 g benzyloxycarbonyl-L-asparagine-4-nitrophenyl ester with the addition of 1 equivalent of pyridine for 48 hours at 20°. The residue left after vacuum evaporation was treated with ethyl acetate and potassium hydrogen sulfate solutions simultaneously; the thick precipitate formed was filtered off and then recrystallised from ethanol/petroleum ether. F = 174° - 175° (Z);[α]D20 = + 13.8° (c = 1.0; in pyridine). Yield = 70 g (71 % of the theoretical amount).
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