Example 250
The structure of the compound of Example 250 is depicted in FIG. 1.
The structure of the compound of Example 250 is depicted in FIG. 1.
(+)-Sodium L-ascorbate (4.7 mg, 0.02 mmol) was added to a solution of the foregoing compound (25 mg, 0.01 mmol), N-but-3-yn-1-yl-N2,N6-dipent-4-ynoyl-L-lysinamide (2.103 mg, 5.88 μmol) and CuSO4.5H2O (5.88 mg, 0.02 mmol) in t-BuOH (5 mL)/H2O (10 mL) under N2 atmosphere. The solution turned milky. After 4 hours the reaction was quenched with aqueous Na2CO3 (10%, 0.050 mL, 0.05 mmol) and filtered. The filtrate was lyophilized and the residue was purified by preparative RP-HPLC (Column: Waters XSelect CSH C18 ODB 5 μm 150×19 mm; mobile phase: A—H2O/TFA 100/0.15 and B—MeCN with a gradient 5% B for 0.5 min, 5-36% B in 1.5 min, 36-41% B in 14 min; flow 30 mL/min at rt, detection 230 nm) to give the title compound (6.8 mg, 9%). HRMS: calculated for (C305H432F3N81O72S9+4H)4+1682.5096; found (ESI [M+4H]4+) 1682.5154, purity 97%.
