@article {49818,
	title = {Atom-economical and scalable asymmetric synthesis of daridorexant key starting material (S)-2-methylproline via the memory of chirality},
	journal = {Organic Process Research \& Development},
	volume = {29},
	year = {2025},
	month = {DEC},
	pages = {3223-3228},
	type = {Article},
	abstract = {<p>
	alpha-Methylproline is a key starting material (KSM) for important drugs, such as Daridorexant, Veliparib, Trofinetide, Enlicitide chloride, and Usnoflast. A practical and scalable asymmetric synthesis of (S)-2-methylproline and its derivatives has been disclosed here using a diketopiperazine intermediate-based strategy that leverages the memory of chirality. Commencing from an inexpensive starting material, l-proline, it proceeds through dimerization and alkylation, followed by hydrolysis under mild conditions, avoiding column chromatography to furnish enantiomerically pure (S)-2-methylproline.HCl, which was also converted to (S)-Boc-2-methylproline and (S)-2-methylproline methyl ester.HCl. In contrast to prior multistep approaches, which rely on expensive chiral auxiliaries and hazardous reagents, this concise three-step route offers operational simplicity, scalability, and superior stereochemical control, making it an attractive method for the synthesis of proline-derived building blocks for peptidomimetics and pharmaceutical applications.</p>
},
	keywords = {alpha-methylproline, atom economy, memoryof chirality, Stereoselective},
	issn = {1083-6160},
	doi = {10.1021/acs.oprd.5c00366},
	author = {Bhatt, Gaurang J. and Kumar, Shubham and Mhaske, Santosh B.}
}
@article {49533,
	title = {Organophotoredox-catalyzed decarboxylative C-O/N/S bond formation: access to ampakine APIs and quinazolinone alkaloids},
	journal = {Organic Letters},
	volume = {27},
	year = {2025},
	month = {APR},
	pages = {3871-3876},
	type = {Article},
	abstract = {<p>
	This study describes a novel and general protocol featuring organophotoredox-catalyzed intramolecular decarboxylative construction of carbon-heteroatom (oxygen, nitrogen, and sulfur) bonds, enabling direct access to ampakine APIs (CX-614 and CX-554), quinazolinone alkaloids (deoxyvasicinone and mackinazolinone), and thiazinone scaffolds as well as their congeners with broad functional group tolerance and scalability. Mechanistic studies suggest a radical-polar crossover pathway via single-electron oxidation.</p>
},
	issn = {1523-7060},
	doi = {10.1021/acs.orglett.5c00565},
	author = {Sonavane, Sameer R. and Kale, Tushar B. and Bhatt, Gaurang J. and Mhaske, Santosh B.}
}
