49776-70-7Relevant articles and documents
Rearrangement Approaches to Cyclic Skeletons. IV. The Total Synthesis of (+/-)-Pinguisone and (+/-)-Deoxopinguisone Based on Photochemical Acyl Migration of a Bicyclonon-6-en-2-one
Uyehara, Tadao,Kabasawa, Yasuhiro,Kato, Tadahiro
, p. 2521 - 2528 (2007/10/02)
The total synthesis of (+/-)-Pinguisone (2) and (/-)-deoxopinguisone (3), fused ring sesquiterpenes, has been achieved starting from 1-methoxy-3,4,5-trimethylbenzene. 1-Methoxy-4,5,endo-8-trimethylbicyclonon-5-en-2-one (9) was prepared selectively via facial selective Diels-Alder reaction of the diene derived from the benzene and 2-chloroacrylonitrile.Ring enlargement of 9 using (CH3)3SiCHN2 and BF3 etherate gave the corresponding bicyclooct-en-2-one (8).The photochemical acyl migration of 8 gave the fused-ring compound (7).The fourth methyl was introduced selectively by the conjugate addition of (CH3)2CuLi to the spironon-8-ene-3,2'-dioxolan>-7-one prepared from 7.Each furan ring of 2 and 3 was constructed via the corresponding butenolide derived from the γ-keto acid by acid-catalyzed dehydration.
Sesquiterpenes of Porella vernicosa (Hepaticae)
Asakawa,Aratani
, p. 1469 - 1470 (2007/10/10)
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