Lithium Hydroxide → 4-((S)-8-(3-(((S)-2-(4-((S)-2-((S)-2-amino-3-methylbutanamido)propanamido)phenyl)-7-methoxy-5-oxo-5,11a-dihydro-1H-benzo[e]pyrrolo[1,2-a][1,4]diazepin-8-yl)oxy)propoxy)-7-methoxy-5-oxo-5,11a-dihydro-1H-benzo[e]pyrrolo[1,2-a][1,4]diazepin-2-yl)benzoic acid

Participants

Reaction Steps

To 9 (20 mg) in THF/CH3OH (2 mL) was added a lithium hydroxide solution (1 mL of a 0.1 M solution). The reaction mixture was stirred at an ambient temperature. At 5 hours, LC-MS revealed approximately a 30% conversion to desired product with significant decomposition. The reaction mixture was cooled to −80° C. for 16 hours. LC-MS showed a ˜1:1 mixture of 10 and 9. The reaction mixture was neutralized with 0.1N HCl (˜1 mL) and was concentrated to approximately 1 mL. DMSO (1 mL) and CH3CN (1 mL) were added, and the mixture was purified by preparatory reverse-phase HPLC. Product containing fractions were combined, frozen and lyophilized. This resulted in 1.7 mg (9%) of 10 as a yellow film: MS (ES+) m/z 938 [M+H]+.

Provenance & Evidence