Total syntheses of (+/-)-crinine, (+/-)-crinamine, and (+/-)-6a-epi-crinamine via the regioselective synthesis and Diels-Alder reaction of 3-aryl-5-bromo-2-pyrone.
We have devised a new unified synthetic protocol to (+/-)-crinine, (+/-)-crinamine, and (+/-)-6a- epi-crinamine from the Diels-Alder cycloadduct of 3-(3,4-methylenedioxyphenyl)-5-bromo-2-pyrone with TBS vinyl ether. The requisite 3-(3,4-methylenedioxyphenyl)-5-bromo-2-pyrone was prepared from the C3-selective Stille coupling reaction of 3,5-dibromo-2-pyrone. Also noted is that the vinyl bromide can be used as a handle for further derivatization.
Nguyen
Thanh Tam
TT
Department of Chemistry, Hanyang University, Seoul, Korea 133-791.
Chang
Jayhyok
J
Jung
Eun-Ju
EJ
Cho
Cheon-Gyu
CG
D047151:Amaryllidaceae Alkaloids / Q000138:chemical synthesis*; D011753:Pyrones / Q000737:chemistry*; D013237:Stereoisomerism
D047151:Amaryllidaceae Alkaloids; D011753:Pyrones; C528221:crinine; C411129:crinamine