Phakellin (3), a natural product isolated from marine organisms, has been studied for

Chapter 3, Problem 3.69

(choose chapter or problem)

Phakellin (3), a natural product isolated from marine organisms, has been studied for its potential use as an antibiotic agent. During studies aimed at developing a strategy for the synthesis of phakellin and its derivatives, compound 1 was investigated as a potential precursor (Org. Lett. 2002, 4, 26452648): N N O O H H 1 N Li (LDA) 2 N N O N N H H2N 3 @ ! 1 (a) Identify the most acidic proton in compound 1, draw the corresponding conjugate base, 2, and justify your choice. (b) Using a quantitative argument based on pKa values as well as a qualitative argument based on structural comparisons, justify why lithium diisopropyl amide (LDA) is a suitable base to deprotonate 1. (c) Draw a mechanism for the conversion of 1 to 2.