<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bhatt, Gaurang J.</style></author><author><style face="normal" font="default" size="100%">Kumar, Shubham</style></author><author><style face="normal" font="default" size="100%">Mhaske, Santosh B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Atom-economical and scalable asymmetric synthesis of daridorexant key starting material (S)-2-methylproline via the memory of chirality</style></title><secondary-title><style face="normal" font="default" size="100%">Organic Process Research &amp; Development</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">alpha-methylproline</style></keyword><keyword><style  face="normal" font="default" size="100%">atom economy</style></keyword><keyword><style  face="normal" font="default" size="100%">memoryof chirality</style></keyword><keyword><style  face="normal" font="default" size="100%">Stereoselective</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2025</style></year><pub-dates><date><style  face="normal" font="default" size="100%">DEC</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">3223-3228</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	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.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
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	3.6&lt;/p&gt;
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