Unusual Conformation and Photoisomerization of Retinochrome Analogues with 11-Methylretinals
作者:Kazuo Tsujimoto、Yasuhiro Shirasaka、Taku Mizukami、Mamoru Ohashi
DOI:10.1246/cl.1997.813
日期:1997.8
NOESY measurement. The formed retinochrome-analogues with 11-Me-, 11-Me-13-deMe- and 11-Me-9,13-dideMe-retinals showed their absorption maxima at 450, 470 and 470 nm, respectively. The enzymatic photoisomerization of their retinochrome-analogues gave the 11-cis isomers in 90-91 % regioselectivity. The CD spectra of 11-methylretinochrome exhibited the intense β-band with extremely weak α-band.
合成了三种 11-甲基视黄醛,以阐明甲基取代对视黄色素类似物形成及其性质的影响。基于 NOESY 测量发现 11-甲基视黄醛的稳定构象为 6,10,12-tri-S-cis 构象。形成的具有 11-Me-、11-Me-13-deMe-和 11-Me-9,13-dideMe-视黄醛的视黄色素类似物分别在 450、470 和 470 nm 处显示出它们的吸收最大值。它们的视黄色素类似物的酶促光异构化产生了 90-91% 区域选择性的 11-顺式异构体。11-甲基视黄色素的CD光谱表现出强烈的β-带和极弱的α-带。