Systematic synthesis of Bis-THF ring cores in annonaceous acetogenins

Systematic synthesis of bis-THF ring cores, synthetic intermediates of adjacent bis-THF annonaceous acetogenins, has been achieved by asymmetric alkynylation and subsequent stereodivergent THF ring formation. The asymmetric alkynylation of alpha-tetrahydrofuranic aldehyde with (S)-3-butyne-1,2-diol derivatives gave good yields of erythro- and threo-adducts with very high diastereoselectivity. These adducts were converted into four types of bis-THF cores via two kinds of one-pot THF ring formation. [reaction: see text]     

Stereodivergent and reiterative synthesis of bistetrahydrofuran ring cores of annonaceous acetogenins

Eight diastereoisomers of the bistetrahydrofuran ring cores of annonaceous acetogenins have been synthesized by asymmetric alkynylation of alpha-tetrahydrofuranic aldehydes and stereodivergent one-pot tetrahydrofuran (THF) ring formation. In all cases, the asymmetric alkynylation proceeded with very high diastereoselectivity to give eight kinds of optically pure THF cores. We also describe a comparison of the (1)H and (13)C NMR spectral data of the eight isomers and give full details of the THF ring construction.     

Rapid and Simple Determination of a Cationic Surfactant by Adsorption Induced by Vigorous Shaking

A rapid and simple method for the determination of a cationic surfactant is described. The method is based on the formation of an ion associate with tetraphenylporphinetetrasulfonic acid (TPPS) and zephiramine as an example of a cationic surfactant. The ion associate was adsorbed on the inner wall of the vessel by vigorous shaking. After complete removal of the solution in the tube, the ion associate was dissolved with 50% ethanol and measured spectrophotometrically. The proposed method is simple and rapid. The apparent molar absorption coefficient for zephiramine using 20mL of sample and 5mL of eluent was estimated to be 9.01×10⁴Lmol^–1cm^–1 at 415nm. The coefficient of variation for 20.2µg of zephiramine was 5.9% (n=10).     

Photocatalytic self-cleaning coatings to remove oleic acid,an organic pollutant,from cotton fabrics

Cellulose - Some textiles and apparel cannot be laundered, such as astronauts’ clothes on the space station, smart textiles that contain optical fiber electronic devices. Thus, self-cleaning...     

Preparation of isotactic‐rich poly(dimethyl vinylphosphonate) and poly(vinylphosphonic acid) via the anionic polymerization of dimethyl vinylphosphonate

A vinylphosphonate monomer, dimethyl vinylphosphonate (DMVP), has been polymerized by anionic initiators. Anionic polymerization of DMVP with tert‐butyllithium (t‐BuLi) in combination with a Lewis acid, tributylaluminum (n‐Bu₃Al), in toluene proceeded smoothly to give an isotactic‐rich poly(dimethyl vinylphosphonate) (PDMVP) with relatively narrow molecular weight distribution. Although all the PDMVPs were soluble in water, the isotactic‐rich PDMVP was insoluble in acetone and in chloroform which are good solvents for an atactic PDMVP prepared by radical polymerization. The isotactic‐rich PDMVP showed higher thermal property than that of the atactic PDMVP. Moreover, we successfully prepared poly(vinylphosphonic acid) (PVPA) through the hydrolysis of the isotactic‐rich PDMVP, which formed a highly transparent, self‐standing film. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1677–1682, 2010     

Grayscale-Memory Spatial Light Modulator with Polymer-Dispersed Phase-Transition Liquid Crystal

A new storage-type spatial light modulator has been developed which uses a polymer-dispersed phase-transition liquid crystal film and a photoconductor for high-brightness projection displays. The liquid crystal film containing micrometer-sized chiral nematic liquid crystal domains subdivided by a unique honeycomb polymer network functions as a memory layer for an input image. The liquid crystal domains independently maintain the binary alignment states in the opaque (light-scattering) cholesteric phase or transparent nematic phase. Grayscale images can be displayed according to the spatial distribution of the bistable liquid crystal domains. The device exhibits rapid response of a few ms and a limiting resolution of 32 lp/mm. It has the advantages of high transmittance without polarizers and ease of fabrication due to the free-standing liquid crystal film.     

Fc-binding antibody-recruiting molecules exploit endogenous antibodies for anti-tumor immune responses

Redirecting endogenous antibodies in the bloodstream to tumor cells using synthetic molecules is a promising approach to trigger anti-tumor immune responses. However, current molecular designs only enable the use of a small fraction of endogenous antibodies, limiting the therapeutic potential. Here, we report Fc-binding antibody-recruiting molecules (Fc-ARMs) as the first example addressing this issue. Fc-ARMs are composed of an Fc-binding peptide and a targeting ligand, enabling the exploitation of endogenous antibodies through constant affinity to the Fc region of antibodies, whose sequence is conserved in contrast to the Fab region. We show that Fc-ARM targeting folate receptor-α (FR-α) redirects a clinically used antibody mixture to FR-α⁺ cancer cells, resulting in cancer cell lysis by natural killer cells in vitro. Fc-ARMs successfully interacted with antibodies in vivo and accumulated in tumors. Furthermore, Fc-ARMs recruited antibodies to suppress tumor growth in a mouse model. Thus, Fc-ARMs have the potential to be a novel class of cancer immunotherapeutic agents.

Fc-binding antibody-recruiting molecules provide robust and sufficient opportunities to employ endogenous antibodies for anti-tumor immune responses.