The formation and stability of flavans with 2,3-cis-3,4-cis configuration

被引:12
作者
Coetzee, J
Malan, E
Ferreira, D
机构
[1] Univ Orange Free State, Dept Chem, ZA-9300 Bloemfontein, South Africa
[2] Univ Mississippi, Sch Pharm, Pharmaceut Sci Res Inst, Natl Ctr Nat Prod Res, University, MS 38677 USA
关键词
flavanoids; stereoselection; neighbouring group effects; thioethers;
D O I
10.1016/S0040-4020(99)00558-X
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
Treatment of 4 beta-chloroepioritin tri-O-methylether with phenylmethanethiol under neutral conditions affords both the 4 alpha- and 4 beta-substituted epioritin derivatives. The stereochemical course of the reaction is of relevance to the thiolysis of 5-oxy (A-ring) proanthocyanidins and to the conspicuous stability of the 7, 8-dihydroxy-2,3-cis-3,4-cis-flavan-3,4-diols, teracacidin and melacacidin, and of some of their all-cis (C-ring) oligomers. (C) 1999 Elsevier Science Ltd. Atl rights reserved.
引用
收藏
页码:9999 / 10004
页数:6
相关论文
共 17 条
[1]   DEGRADATION OF CONDENSED TANNINS - STRUCTURE OF TANNIN FROM COMMON HEATHER [J].
BETTS, MJ ;
BROWN, BR ;
BROWN, PE ;
PIKE, WT .
CHEMICAL COMMUNICATIONS, 1967, (21) :1110-&
[2]   FLAVAN DERIVATIVES .3. MELACACIDIN AND ISOMELACACIDIN FROM ACACIA SPECIES [J].
CLARKLEWIS, JW ;
MORTIMER, PI .
JOURNAL OF THE CHEMICAL SOCIETY, 1960, (OCT) :4106-4111
[3]  
CLARKLEWIS JW, 1968, AUST J CHEM, V21, P2059
[4]  
CLARKLEWIS JW, 1967, AUST J CHEM, V20, P2152
[5]   Oligomeric flavanoids - Part 29: Structure and synthesis of novel ether-linked [4-O-4]bis-teracacinidins [J].
Coetzee, J ;
Malan, E ;
Ferreira, D .
TETRAHEDRON, 1998, 54 (31) :9153-9160
[6]   Oligomeric flavanoids. Part 28. Structure and synthesis of ether-linked (4-O-3)-bis-teracacidins, a novel class of naturally occurring proanthocyanidins [J].
Coetzee, J ;
Malan, E ;
Ferreira, D .
JOURNAL OF CHEMICAL RESEARCH, 1998, (09) :526-527
[7]  
COETZEE J, 1998, J CHEM RES M, P2287