Synthesis of Geometrically Pure 11 Z-Retinal Derivatives for Elucidation of Visual Systems by Molecular Recognition
Grant-in-Aid for Scientific Research (B).
|Allocation Type||Single-year Grants|
|Research Institution||kyoto Pharmaceutical University(1999-2000)|
Okayama University of Science(1998)
UENISHI Jun'ichi Faculty of Pharmaceutical Science, kyoto Pharmaceutical University, Professor, 薬学部, 教授 (50167285)
|Project Period (FY)
1998 – 2000
Completed(Fiscal Year 2000)
|Budget Amount *help
¥3,400,000 (Direct Cost : ¥3,400,000)
Fiscal Year 2000 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Fiscal Year 1999 : ¥1,800,000 (Direct Cost : ¥1,800,000)
|Keywords||Z-alkene / 11Z-retinal / Suzuki coupling / hydrogenolysis / stereospecific reaction / Geometrical control / 1,1-ジブロモアルケン / パラジウム / ニッケル / クロスカップリング / 三置換アルケン / 合成 / 立体特異的 / ポリエン / 異性化 / 視覚|
In this research, the following results were obtained during three years.
Stereocontrolled synthesis of 11Z-retinal by Suzuki coupling of C_1-C_<12> and C_<13>-C_<15> fragments
(1) Stereoselective hydrogenolysis of 1, 1-dibromo-1-alkene was performed by Pd catalyzed reduction with tributyltin hydride giving (Z)-1-bromo-1-alkene with excellent stereo-selectivity in good yield. A (Z)-bromotetraene corresponding to a C_1-C_<12> fragment of 11Z-retinal was prepared by this selective hydrogenolysis.
(2) Trisubstituted alkenylboronic acid corresponding to a C_<13>-C_<15> fragment of 11Z-retinal was prepared stereolselectively. These two fragments were coupled by Suzuki reaction catalyzed by Pd catalyst to give the complete 11Z-retinal skeleton. After transformation of terminal silyl ether to aldehyde gave stereochemically pure 11Z-retinal.
Stereocontrolled synthesis of 13-ehtyl substituted 11Z-retinal by Suzuki coupling of C_1-C_<10> and C_<11>-C_<15> fragments
(1) Trienylboronic acid corresponding to a C_1-C_<10> fragment of 11Z-retinal was prepared from dieneyne through idodotriene.
(2) Stepwise cross coupling reactions of 1, 1-dibromo-1-alkene by Sonogashira reaction and Kumada-Tamao reaction gave stereochemically pure trisubstituted enyne. Base on this method, 13-alkyl substituted iododiene corresponding to a C_<11>-C_<15> fragment of 11Z-retinal was synthesized.
(3) The two fragments were combined by Suzuki coupling to give 13-ethyl substituted 11Z-retinal skeleton under the stereocontrolled manner.
Research Output (7results)