Synthesis of the Integrastatin Nucleus Using the Ramberg - Bäcklund Reaction

Organic Letters

Volumn 5, Issue 23, 2003, Pages 4441-4444

  Foot, Jonathan S ^a   Giblin, Gerard M P ^b   Taylor, Richard J K ^a  

^a UNIVERSITY OF YORK   (United Kingdom)

^b GLAXOSMITHKLINE   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

INTEGRASE INHIBITOR; INTEGRASTATIN A; INTEGRASTATIN B; LEWIS ACID; NATURAL PRODUCT; UNCLASSIFIED DRUG;

ARTICLE; CHEMICAL REACTION; CYCLIZATION; DRUG SYNTHESIS; OXIDATION; X RAY CRYSTALLOGRAPHY;

EID: 0345359259     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol035786v     Document Type: Article

References (17)

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17. Procedure for Oxidation of 17. To a stirred solution of 17 (0.03 g, 0.12 mmol), PDC (0.26 g, 0.7 mmol), and Celite (0.2 g) in benzene (3.5 mL) at 6-10°C under nitrogen was added TBHP (5.5 M in decane, 0.13 mL, 0.7 mmol). The reaction mixture was stirred below 10°C for 4 days, with further addition of TBHP (2 x 0.13 mL) after 36 and 72 h. Filtration of the reaction through a pad of Celite, washing with EtOAc, and removal of solvent in vacuo, followed by purification (flash chromatography, eluting in 15:1 petroleum ether/EtOAc), afforded the integrastatin nucleus, 2 (0.013 g, 41%), and unreacted 17 (0.014 g, 47% recovered).