We prepared 6,6-F2-AcAP in eight steps from N,O-protected 4-oxoproline. The key step was a Dieckmann condensation that annulated the A ring onto the B ring. When we subjected 6,6-F2-AcAP to LolO, the enzyme was able to catalyze both the hydroxylation and the cycloetherification to make 6,6-F2-NANL, suggesting that the LolO has a flexible active site, as it did not differentiate between the natural substrate (AcAP) and this difluorinated analog of AcAP. Also, it suggested that cycloetherification mechanism most likely involves a C(7) radical as opposed to a C(7) carbocation. Then, we prepared 7,7-F2-AcAP from 3-oxoproline in 17 steps where the key step was radical cyclization to make the pyrrolizidine ring in 5-exo-dig fashion. By contrast, when we subjected the difluorinated analog 7,7-F2-AcAP to LolO, the cycloetherification step was shut down completely, giving 2-OH-7,7-F2-AcAP as the sole product. Because 7,7-F2-AcAP completely blocks the cycloetherification step, it may be used in the future to further understand the cycloetherification of 2-hydroxy-AcAP by accumulating and characterizing the LolO intermediates responsible for cycloetherification.