Highly stereoselective and stereodivergent synthesis of four types of THF cores in acetogenins using a C4-chiral building block.
[reaction: see text] Four stereoisomers of the THF cores, synthetic intermediates of acetogenins, have been synthesized with high diastereoselectivity by asymmetric alkynylation and subsequent stereodivergent THF ring formation. The asymmetric alkynylation of alpha-oxyaldehyde with (S)-3-butyne-1,2-diol derivatives (C4-unit) gave good yields of syn and anti adducts with >97:3 dr and 94:6 dr, respectively. These adducts were converted into the four types of THF compounds via one-pot THF formation or via intramolecular Williamson synthesis.
Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
Naoyoshi
N
Maezaki
Naoto
N
Kojima
Mikito
M
Asai
Hiroaki
H
Tominaga
Tetsuaki
T
Tanaka
D000447:Aldehydes / Q000737:chemistry; D000480:Alkynes / Q000737:chemistry; D029061:Annonaceae / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis; D003500:Cyclization; D005663:Furans / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000447:Aldehydes; D000480:Alkynes; D000970:Antineoplastic Agents; D005663:Furans