@article {48668,
	title = {Total synthesis, structure elucidation and expanded bioactivity of icosalide A: effect of lipophilicity and ester to amide substitution on its bioactivity},
	journal = {Organic \& Biomolecular Chemistry},
	volume = {21},
	year = {2023},
	month = {JUL},
	pages = {5725-5731},
	type = {Article},
	abstract = {<p>
	The first total synthesis of icosalide A, an antibacterial depsipeptide that is unique in that it contains two lipophilic beta-hydroxy acids, has been achieved by following Fmoc solid-phase peptide synthesis in combination with solution-phase synthesis. The ambiguity in the absolute stereochemistry of icosalide A has been resolved by synthesizing the reported structures and other relevant diastereomers of icosalides and comparing their NMR data. NMR-based structure elucidation of icosalide A revealed a well-folded structure with cross-strand hydrogen bonds similar to the anti-parallel beta-sheet conformation in peptides and displayed a synergistic juxtaposition of the aliphatic sidechains. 12 analogues of icosalide A were synthesized by varying the constituent lipophilic beta-hydroxy acid residues, and their biological activities against Bacillus thuringiensis and Paenibacillus dendritiformis were explored. Most of these icosalide analogues showed an MIC of 12.5 \&amp; mu;g mL(-1) against both bacteria. Swarming inhibition by icosalides was least in B. thuringiensis (8.3\%) compared to that in P. dendritiformis (33\%). Furthermore, this is the first report of icosalides showing assured inhibitory action (MIC between 2 and 10 \&amp; mu;g mL(-1)) against the active stage of Mycobacterium tuberculosis and cancer cell lines such as HeLa and ThP1. This study could help optimize icosalides for anti-TB, antibacterial, and anti-cancer activities.</p>
},
	issn = {1477-0520},
	doi = {10.1039/d3ob00809f},
	author = {Dangi, Abha and Pande, Bharat and Agrawal, Sonia and Sarkar, Dhiman and Vamkudoth, Koteswara Rao and Marelli, Udaya Kiran}
}
