First total syntheses of the phytotoxins solanapyrones D and E via the domino Michael protocol.
The phytotoxins solanapyrones D (1) and E (2) have been synthesized from the decalone prepared by the domino Michael reaction of the kinetic enolate of optically pure acetylcyclohexene with methyl crotonate. The decalone was transformed into a solanapyrone core by equilibration into thermodynamically stable trans-decalone (11), dehydroxylation, and dehydration. Condensation of a methyl acetoacetate equivalent followed by cyclization installed a pyrone moiety. Introduction of a formyl or hydroxymethyl unit into the pyrone ring via Pummerer related reactions furnished solanapyrones D (1) and E (2).
Hagiwara
Hisahiro
H
Graduate School of Science and Technology, Niigata University, 8050, 2-nocho, Ikarashi, Niigata 950-2181, Japan. hagiwara@gs.nigata-u.ac.jp
Kobayashi
Katsuhiro
K
Miya
Shigeki
S
Hoshi
Takashi
T
Suzuki
Toshio
T
Ando
Masayoshi
M
Okamoto
Tetsuji
T
Kobayashi
Masaki
M
Yamamoto
Isao
I
Ohtsubo
Satoru
S
Kato
Michiharu
M
Uda
Hisashi
H
D000528:Alternaria / Q000737:chemistry; D002625:Chemistry, Organic / Q000379:methods; D003500:Cyclization; D007700:Kinetics; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000138:chemical synthesis* / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular; D011753:Pyrones / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
D009281:Naphthalenes; D011753:Pyrones; C113269:solanapyrone B; C113266:solanapyrone A