N#N.[CH3:3][C:4]([CH3:29])([O:6][C:7]([NH:9][C@H:10]([C:26]([OH:28])=[O:27])[CH2:11][CH2:12][CH2:13][CH2:14][NH:15][C:16]([O:18][CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)=[O:17])=[O:8])[CH3:5].[N+:30](=C)=[N-:31].[C:33](O)(=O)[CH3:34].N#N.CC(C)(OC(N[C@H](C(OC)=O)CCCCNC(OCC1C=CC=CC=1)=O)=O)C>C(OCC)(=O)C.CC(C)=O.CCCCCC>[N:30]#[N:31].[CH3:5][C:4]([CH3:29])([O:6][C:7]([NH:9][C@H:10]([C:26]([O:28][CH2:33][CH3:34])=[O:27])[CH2:11][CH2:12][CH2:13][CH2:14][NH:15][C:16]([O:18][CH2:19][C:20]1[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=1)=[O:17])=[O:8])[CH3:3]N2 -[(1,1-Dimethylethoxy)carbonyl]-N6 -[(phenylmethoxy)carbonyl]-L-lysine (5.48 g., 14.4 mmole) is dissolved in ethyl acetate (130 ml.). Diazomethane is added until a yellow color persists. Acetic acid is added to quench the excess diazomethane, and the volatiles are evaporated. The residue is partitioned between ethyl acetate and saturated sodium bicarbonate, the organic layer is dried over sodium sulfate, filtered, and then the volatiles are evaporated. Purification of the residue by column chromatography on LPS-1 silica eluting with 30% ethyl acetate/hexane yields 4.0 g. of N2 -[(1,1-dimethylethoxy)carbonyl]-N6 -[(phenylmethoxy)carbonyl]-L-lysine, methyl ester. TLC (silica gel; hexane:acetone, 1:1) Rf =0.69.
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