先前已证明含有膦酸酯代替 sn-2 位置的酯的磷脂类似物是分泌型磷脂酶 A 2 的紧密结合竞争性抑制剂。制备并分析了这些化合物的变体,其中磷脂极性头基的结构已经改变,作为来自眼镜蛇毒液、猪和牛胰腺以及人滑液的磷脂酶 A 2 的抑制剂。在酶进行催化而不从囊泡解吸的条件下,使用带负电荷的底物囊泡进行抑制剂效力的动力学测量(滑移模式)
The azulene ring as a structural element in liquid crystals
作者:Siân E. Estdale、Roger Brettle、David A. Dunmur、Charles M. Marson
DOI:10.1039/a606139g
日期:——
A new approach to the synthesis of azulene liquid crystals is described
based on Hafner’s procedure involving reaction of a pyridinium salt
with a cyclopentadienide. The preparation of a variety of liquid
crystalline materials using this method is described. Variants are
reported with single substituents on the azulene ring in the 6-position
and doubly substituted in the 2, 6- positions. The effect of the azulene
ring as a core or dipolar terminal structural element is explored.
6-(5-Alkyl-1,3-dioxan-2-yl)azulenes are shown to exhibit smectic A phases
and 2-cyclohexyl-6-(5-tridecyl-1,3-dioxan-2-yl)azulene show smectic A and
B phases. Phase characterisation of the materials is recorded together
with X-ray measurements on the smectic A phase of one representative
compound. Results of dichroism studies on the azulene mesogens are also
briefly reviewed.
Competitive inhibition of interfacial catalysis by phospholipase A2: differential interaction of inhibitors with the vesicle interface as a controlling factor of inhibitor potency
作者:Hung Kuei Lin、Michael H. Gelb
DOI:10.1021/ja00063a012
日期:1993.5
Phospholipidanaloguescontaining a phosphonate in place of the ester at the sn-2 position have been previously shown to be tight-binding competitive inhibitors of secreted phospholipases A 2 . Variants of these compounds in which the structure of the phospholipid polar headgroup has been changed were prepared and analyzed as inhibitors of the phospholipases A 2 from the and cobra venom, porcine and
先前已证明含有膦酸酯代替 sn-2 位置的酯的磷脂类似物是分泌型磷脂酶 A 2 的紧密结合竞争性抑制剂。制备并分析了这些化合物的变体,其中磷脂极性头基的结构已经改变,作为来自眼镜蛇毒液、猪和牛胰腺以及人滑液的磷脂酶 A 2 的抑制剂。在酶进行催化而不从囊泡解吸的条件下,使用带负电荷的底物囊泡进行抑制剂效力的动力学测量(滑移模式)
Mesogenic, optical, and dielectric properties of 5-substituted 2-[12-(4-pentyloxyphenyl)-p-carboran-1-yl] [1,3]dioxanes
Two homologous series of carborane-containing dioxanes 1[n] and 2[n] (n = 1–10) were prepared and their mesogenic properties investigated. All compounds exhibit nematic behavior and three members of series 2[n] show an E phase. Numerical analysis of the clearing temperatures gave a limiting value TNI(∞) of 89 °C for series 2[n] and indicated conformational flexibility of the dioxane ring. Investigations of three-ring derivative 1[4] gave Δn = 0.17, S = 0.53, and Δε = +0.4 ± 0.1 at 85 °C. Extrapolation of dielectric data for dilute solutions of 1[4] in 6-CHBT gave Δε = +0.4 ± 0.25 at 24 °C. Modelling of dielectric results with the Maier–Meier equation demonstrated that conformers with a higher β angle are preferred, which is consistent with conformational selection for the most elongated conformers.
Liquid crystalline mixtures including 2-phenylpyridine compounds
申请人:Hoffmann-La Roche Inc.
公开号:US05104569A1
公开(公告)日:1992-04-14
Compounds of the formula ##STR1## wherein R.sup.1 is alkyl or alkenyl; Z.sup.1 denotes a single covalent bond or --CH.sub.2 CH.sub.2 --; ring A represents unsubstituted or halogen- and/or methyl-substituted 1,4-phenylene; Z.sup.2 denotes a single covalent bond, oxygen or --CH.sub.2 O--; and R.sup.2 is an unsubstituted or halogen-substituted alkyl or alkenyl group, their preparation as well as liquid crystalline mixtures and their use for electro-optical purposes.
Liquid Crystal Materials with Sulfur Atoms Incorporated in the Principal Structure. VI. Optically Active New Smectic Liquid Crystal Compounds with 1,3-Oxathiane or 1,3-Dithiane Ring
(+)-2-Methylbutyl p-(5-alkyl-1,3-oxathian-2-yl)benzoate and -cinnamate (7) were synthesized. The mesomorphic behavior of these compounds were measured. Though (+)-2-methylbutyl p-(5-alkyl-1,3-oxathian-2-yl)benzoate did not exhibit any liquid-crystal phase, the corresponding 1,3-dithiane compounds (8-1, 8-2, and 8-3) and compound (7-4) having R’ of a normal alkyl chain exhibited a smectic phase. This