N,N-acetals as N-acyliminium ion precursors: synthesis and absolute stereochemistry of epiquinamide.
A stereoselective synthesis of (+)-epiquinamide is presented in combination with determination of the absolute configuration of the natural product. Key steps in the sequence involved chemoenzymatic formation of an enantiomerically pure cyanohydrin, reductive cyclization to the corresponding cyclic N,N-acetal, and subsequent conversion into a suitable N-acyliminium ion precursor to enable construction of the second ring.
Wijdeven
Marloes A
MA
Radboud University Nijmegen, Institute for Molecules and Materials, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands.
Wijtmans
Roel
R
van den Berg
Rutger J F
RJ
Noorduin
Wim
W
Schoemaker
Hans E
HE
Sonke
Theo
T
van Delft
Floris L
FL
Blaauw
Richard H
RH
Fitch
Richard W
RW
Spande
Thomas F
TF
Daly
John W
JW
Rutjes
Floris P J T
FP
D000080:Acetals / Q000737:chemistry*; D000818:Animals; D001001:Anura; D001688:Biological Products / Q000138:chemical synthesis / Q000737:chemistry; D002412:Cations / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D011807:Quinolizines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013379:Substrate Specificity
D000080:Acetals; D001688:Biological Products; D002412:Cations; D007097:Imines; D011807:Quinolizines; C481035:epiquinamide