title: Pentacyclic furanosteroids: the synthesis of potential kinase inhibitors related to viridin and wortmannolone.
abstract: A regiocontrolled intermolecular Diels-Alder reaction of an o-benzoquinone followed by an intramolecular nitrile oxide cyclization is employed to prepare the BCD fragment of viridin. The AE segment is attached to it by means of an intramolecular Diels-Alder reaction of an o-benzoquinone monoketal generated in situ from tricycle 15 and 5-trimethylsilyl-2E,4E-pentadienol 20. The silyl substituent at C-1 of the pentacyclic product directs the dihydroxylation of the C2-C3 double bond to its beta-face. Various transformations of the 1alpha-trimethylsilyl-2beta,3beta-dihydroxy pentacycle into several others with oxygen substituents in ring A are described. One of these products 40 possesses the same structure and relative stereochemistry in rings A, B, and E as that of the natural product wortmannolone 3.
authors: Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
authors: Yunhui
authors: Y
authors: Lang
authors: Fabio E S
authors: FE
authors: Souza
authors: Xinshe
authors: X
authors: Xu
authors: Nicholas J
authors: NJ
authors: Taylor
authors: Abdeljalil
authors: A
authors: Assoud
authors: Russell
authors: R
authors: Rodrigo
mesh_terms: D000730:Androstadienes / Q000138:chemical synthesis* / Q000737:chemistry; D000736:Androstenes / Q000138:chemical synthesis* / Q000737:chemistry; D001430:Bacteriocins / Q000138:chemical synthesis* / Q000737:chemistry; D016227:Benzoquinones / Q000737:chemistry; D003500:Cyclization; D015394:Molecular Structure; D047428:Protein Kinase Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; D000736:Androstenes; D001430:Bacteriocins; D016227:Benzoquinones; D047428:Protein Kinase Inhibitors; C025225:2-benzoquinone; C012097:viridin; D000077191:Wortmannin