| Co-Investigator(Kenkyū-buntansha) |
YOSHIDA Yasuko Nippon Gaishi Ltd., Bio Research, Research Associate, バイオ研究課, 主任研究員
NAKAMURA Kaoru Kyoto Univ., Institute, Associate Professor, 化学研究所, 助教授 (10101239)
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| Budget Amount *help |
¥12,900,000 (Direct Cost: ¥12,900,000)
Fiscal Year 1996: ¥5,300,000 (Direct Cost: ¥5,300,000)
Fiscal Year 1995: ¥7,600,000 (Direct Cost: ¥7,600,000)
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| Research Abstract |
1. Synthesis of Bis (hydroxymethyl) [7] thiaheterohelicene :
We designed a thiaheterohelicene with two hydroxy groups at the terminal aromatic nuclei and synthesized racemic 2,13-bis (hydroxymethyl) dithieno [3,2-e : 3', 2'-e'] benzo [1,2-b : 4,3-b'] bis [1] benzothiophene from readily available 1-hydroxymethyl [1,2-b : 4,3-b'] benzo-dithiophene.
2. Molecular Structure and Crystal Packing of Bis (hydroxymethyl) [7] thia-heterohelicene :
The molecular structure and the crystal packing of racemic [7] helicenediol was determined by X-ray analysis. The [7] helicenediol has C_2 symmetry, and ethanol molecule was included in the crystals in a ratio [7] helicenediol : ethanol=1 : 1 by intermolecular hydrogen bonds. In the crystal cell, the helicenes possessing same helicity (P or M) are aligned in a stacking column along b axis of the crystal.
3. Optical Resolution of Helicenediol by Lipase-catalyzed Transesterification :
The reaction of racemic [7] helicenediol (100mg) with the lipase from Pseudo
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monas cepacia (Amano PS,2.99g) in dichloromethane (100ml) in the presence of molecular sieves 4A (4.37g) at room temperature was terminated close to the 50% esterification point (25h), giving (P) - (+) - [7] helicenediol (44.7mg, 45% yield) in 98% ee and the corresponding monoacetate (40.9mg, 38% yield) and diacetate (15.1mg, 13% yield) which were readily separated by silica gel chromatography. The rotational value of (P) - (+) - [7] helicenediol was [alpha] _D +1973 (c0.055, CHCl_3). Hydrolysis of the monoacetate by NaOH in methanol gave (M) - (-) - [7] helicenediol with 80% ee and the diacetate gave the same enantiomer with 95% ee. In contrast, the transesterification of the racemic [7] helicenediol (100mg) with the lipase from Candida antarctica (Nova CAL, 0.5g) gave (M) - (-) - bis (hydroxymethyl) [7] thiaheterohelicene (43.7mg, 44%yield) with 92% ee and the corresponding monoacetate (57.8mg, 53% yield) and diacetate (3.4mg, 3% yield). The rotational value of (M) - (-) - [7] helicenediol was [alpha]_D -1965 (c0.050, CHCl_3). Less
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