have investigated the regio- and stereochemistry of the reductive dealkoxylation of alkyl aryl ethers. Chiral non-racemic secondary alcohols were converted into the corresponding m-terphenyl or 2-biphenyl ethers either via inversion of configuration under Mitsunobu reaction conditions or with retention of configuration under SNAr conditions. The successive cleavage of the aromatic CO bond occurred
Optically active compound and liquid crystal composition containing same
申请人:CANON KABUSHIKI KAISHA
公开号:EP0301511A1
公开(公告)日:1989-02-01
An optically active, generally mesomorphic compound represented by the following formula (I):
wherein R, denotes an alkyl group having 1 - 18 carbon atoms, R2 denotes an alkyl group having 1 - 12 carbon atoms; X denotes a single bond,
or
or
and
C* denotes an asymmetric carbon atom; k, m and n are respectively 0, 1 or 2 with proviso that k + m + n amounts to 2 or 3; and p is 1 or 2.
由下式(I)表示的具有光学活性的一般介形化合物:
其中 R 表示具有 1 - 18 个碳原子的烷基,R2 表示具有 1 - 12 个碳原子的烷基,X 表示单键、
或
或
和
C*表示不对称碳原子;k、m 和 n 分别为 0、1 或 2,但 k + m + n 为 2 或 3;p 为 1 或 2。
Mesomorphic compound and liquid crystal composition containing same
申请人:CANON KABUSHIKI KAISHA
公开号:EP0316011A2
公开(公告)日:1989-05-17
A mesomorphic compound represented by the formula:
wherein R₁ denotes an alkyl group having 1 - 16 carbon atoms; R₂ denotes an alkyl group having 2 - 10 carbon atoms; X denotes a single bond or -0-; Y denotes -OCH₂-, -OCH₂- or -O-;
Z denotes a single bond,
respectively and independently denote
k, l and n are respectively 0, 1 or 2 satisfying the relation of k+l+n = 2 or 3; C* denotes an asymmetric carbon atom. The mesomorphic compound, when added as a component, provides a liquid crystal composition showing an improved field respective characteristic or is effective in preventing occurrence of a reverse domain.
Optically active ester derivatives, preparation process thereof, liquid crystal materials and a light switching element
申请人:SUMITOMO CHEMICAL COMPANY, LIMITED
公开号:EP0357372A2
公开(公告)日:1990-03-07
Disclosed are herein optically active ester derivatives represented by the formula (I):
(wherein R1 represents an alkyl group having 3 to 20 carbon atoms; R2 represents an optically active alkyl or alkoxyalkyl group having 3 to 15 carbon atoms optionally substituted by halogen atoms; Y represents -O-, -COO- or -OCO-; X represents -COO- or -OCO-; represents a number of 1 or 2; k and m each represents a number of 0 or 1; n represents a numberof 1 to 6), preparation processes therefor, liquid crystal materials containing such easter derivatives as active ingredient, and a light switching element using said liquid crystal materials as liquid crystal element.
Trichoderma-derived selenium nanoparticles foliar fertilizer for reducing crop fungal diseases and toxin contamination
申请人:Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences
公开号:US10807920B2
公开(公告)日:2020-10-20
The present invention relates to a Trichoderma-derived selenium nanoparticles foliar fertilizer which reduces crop fungal diseases and toxin contamination. For the first time, a new type of agricultural composition was disclosed, which is mainly obtained by mixing Trichoderma harzianum culture with selenite, which has a good fungistatic effect. The inventors also screened and obtained a harzianum strain with excellent effect. After fermentation, mixed with selenite and post-processed, the obtained product had a significant effect on resisting harmful fungus and improving disease resistance of the plant.