Smart and concise entry to chiral spiro[cyclopentane-indolizidine]-tetraol diastereomers as a new aza-spirocyclic framework

• Published in: New journal of chemistry Vol. 45; no. 35; pp. 15956 - 15967
• Main Authors: Fra ová, Paula, Marchalín, Štefan, Šafá, Peter, Cve ko, Matej, Moncol, Ján, ídeková, Ivana, Othman, Mohamed, Daïch, Adam
• Format: Journal Article
• Language: English
• Published: CAMBRIDGE Royal Soc Chemistry 21.09.2021; Royal Society of Chemistry
• Subjects: Alkylation; Amides; Carbonyls; Chemistry; Chemistry, Multidisciplinary; Crystallography; Glutamic acid; Metathesis; Physical Sciences; Science & Technology; CARBON; ENANTIOSELECTIVE SYNTHESIS; ENANTIOSPECIFIC SYNTHESIS; PRODUCTS; OXAZOLOPIPERIDONE LACTAMS; CONSTRUCTION; RACEMIC BICYCLIC LACTAMS; SCAFFOLDS; CYCLIZATION; ALKALOIDS
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d1nj02180j

Dihydrofuro[2,3- f ]indolizidinone obtained from biosourced l -glutamic acid ( l -GA) was used advantageously as an advanced building block to prepare affordably in a few steps optically pure spiro[cyclopentane-indolizidine]-tetraol diastereomers as a new oxacarba-spiroindolizidine framework. The sequential approach used for the construction of tetracyclic spiro-compounds' core consists of olefin cis -dihydroxylation, diol protection, and α-carbonyl alkylation followed by alkene ring-closing metathesis as the key step. Chiral oxacarba-spiroindolizidine tetraols were obtained by the sequence of steps consisting of alkene cis -dihydroxylation, diol protection and lactam carbonyl reduction followed ultimately by acetonide deprotection. Synthesis of chiral oxacarba-spiroindolizidine tetraols was achieved by alkene cis -dihydroxylation, diol protection, and lactam carbonyl reduction followed ultimately by acetonide deprotection.