Leaving group effect in the cleavage of picolinate esters catalyzed by hydroxy-functionalized metallomicelles
摘要:
Micellar aggregates of complexes of transition metal ions with the hydroxy-functionalized surfactant 1a are very effective catalysts of the cleavage of activated esters of alpha-amino acids. To ascertain their effectiveness toward unactivated esters, a systematic kinetic study was undertaken employing as substrates the picolinic acid esters 3a-1, the pK(a) of their alcoholic portion spanning more than 12 units from 3.6 to 16. The leaving group effect was investigated in water, pH=6.3, in the absence and presence of CU2+ ions, in the presence of the nonmicellar complex 2-CU2+, and in the presence of micellar aggregates made of 1a-Cu2+ or of its O-methylated analog 1b-Cu2+. In the presence of free metal ions the leaving group effect is negligible in the case of esters with good leaving groups (pK(a)
Leaving group effect in the cleavage of picolinate esters catalyzed by hydroxy-functionalized metallomicelles
摘要:
Micellar aggregates of complexes of transition metal ions with the hydroxy-functionalized surfactant 1a are very effective catalysts of the cleavage of activated esters of alpha-amino acids. To ascertain their effectiveness toward unactivated esters, a systematic kinetic study was undertaken employing as substrates the picolinic acid esters 3a-1, the pK(a) of their alcoholic portion spanning more than 12 units from 3.6 to 16. The leaving group effect was investigated in water, pH=6.3, in the absence and presence of CU2+ ions, in the presence of the nonmicellar complex 2-CU2+, and in the presence of micellar aggregates made of 1a-Cu2+ or of its O-methylated analog 1b-Cu2+. In the presence of free metal ions the leaving group effect is negligible in the case of esters with good leaving groups (pK(a)
[EN] MICROSPORE TRANSFORMATION METHODOLOGY BY MACROINJECTION<br/>[FR] TECHNIQUE DE TRANSFORMATION DE MICROSPORES PAR MACRO-INJECTION
申请人:CA NAT RESEARCH COUNCIL
公开号:WO2012075562A1
公开(公告)日:2012-06-14
A method for introducing a cargo molecule into a microspore of a plant involves macroinjecting a bud of a donor plant in vivo with a complex comprising a nanocarrier and the cargo molecule. The method is particularly useful in a method of transforming plant cells by macroinjection of buds using a nanocarrier:nucleic acid complex. The method preferably involves transformation of microspores in vivo by macroinjection of donor plant buds with a nanocarrier:nucleic acid complex prior to culturing isolated microspores (immature pollen), and subsequent generation of a doubled-haploid homozygous transgenic plant from the transformed microspores.