Novel synthesis of (d,l) trans-chrysanthemic acid involving a β-diketone fragmentation
摘要:
Methyl (d,l) trans-chrysanthemate as well as its cis-diastereoisomer have been prepared from dimethyl dimedone, one of their isomers, in a few steps and with complete control of the relative stereochemistry. (C) 2002 Elsevier Science Ltd. All rights reserved.
Highly enantioselective synthesis of chiral imides and derived products via chiral base desymmetrisation
作者:David J Adams、Alexander J Blake、Paul A Cooke、Christopher D Gill、Nigel S Simpkins
DOI:10.1016/s0040-4020(02)00367-8
日期:2002.6
The enantioselective deprotonation of several ring-fused imides with a chiral base, followed by electrophilic quenching, gives a range of chiral products in good yield and in ≥91% ee. The absolute stereochemistry of two of the products was determined by X-ray crystallography. A number of the imide products were subjected to further, highly regioselective, transformations, including enolate substitution
Novel synthesis of vinyl cyclopropane carboxylic acids: Application to the synthesis of (d,l)- and (d)-cis-chrysanthemic acid
作者:Alain Krief、Dominique Swinnen
DOI:10.1016/0040-4039(96)01410-4
日期:1996.9
5-dimethyl-2-cyclopentenones allows an efficient entry to the bicyclo[3.1.0]hexan-2-one skeleton which proved to be a valuable precursor of vinyl cyclopropane carboxylic acids. Application to the synthesis of (d,l)- and (d)-(cis)-chrysanthemic acid is described.
Fragmentation of 4-Sulfonylbicyclo[3.1.0]hexan-2-ones as the Key Step in the Enantioselective Synthesis of (1<i>R</i>)-<i>cis</i>-Chrysanthemic Acid Involving Desymmetrization of 3,3,6,6-Tetramethylbicyclo[3.1.0]hexane-2,4-dione
作者:Alain Krief、Adrian Kremer
DOI:10.1055/s-2007-970747
日期:——
t-BuOK-H2O (7.6:2.3) in THF or DMSO allows the efficient Grob-type fragmentation of 4-sulfonyl-bicyclo[3.1.0]hexan-2-ones which cannot be achieved by potassium hydroxide in DMSO as we originally described.
Comparison between ‘IgY technology’ from chickens and ‘IgG technology’ from mice for production of tailor-made antibodies
作者:Alain Krief、Jean-Jacques Letesson、Denis Billen
DOI:10.1016/s0040-4039(02)00142-9
日期:2002.3
Antibodies collected from chickens immunized towards a beta-ketoalcohol, key intermediate in the synthesis of chrysanthemic acid. which have been shown to possess similar behavior to those elaborated from mice, offer the enormous advantages of no bleeding and access to large quantities of antibodies by easy extraction of the yolk of the eggs. (C) 2002 Elsevier Science Ltd. All rights reserved.