7766-49-6Relevant academic research and scientific papers
Design of: C 2-symmetric alkaloidal chiral amphiphiles and configurational effects on self-assembly
Tsuchiya, Nana,Ryu, Yunosuke,Muraoka, Takahiro,Oguri, Hiroki
, p. 9305 - 9313 (2018)
Alkaloids are a cornerstone in the development of medicinal and synthetic compounds due to their capability of specific recognition of targeted biomacromolecules, and uses in optical resolution and asymmetric reactions. To explore the untapped potential of the rigid and densely functionalized structures of alkaloids with precisely regulated configurations as optically active core scaffolds of self-assembling molecules, here we report the design, syntheses, chiroptical properties and self-assemblies of C2-symmetric alkaloidal amphiphiles with anti/syn stereochemical variations. Bispyrrolidinoindoline (BPI) was chosen as the optically active core scaffold. It was synthetically modified with hydrophobic alkyl chains and hydrophilic tetraethylene glycol tails to provide amphiphilicity. The anti/syn configurational differences in the amphiphiles significantly influenced the chiroptical, dynamic and supramolecular properties. Amphiphiles with anti-configurations responded to a solvent polarity change by altering their conformations, while the conformational changes of the syn-type amphiphiles were largely restricted. Furthermore, the anti-type amphiphile having the highest structural flexibility showed a characteristic split Cotton effect in an organic medium and formed the largest aggregates upon addition of water with a significant change in the circular dichroism (CD) profile, while amphiphiles having conformational restriction by the syn-configuration or a macrocyclic structure showed monomodal CD signals and afforded significantly smaller aggregates upon addition of water. Hence, the C2-symmetric alkaloidal BPI structure is demonstrated to be a useful core scaffold for supramolecular chemistry to design amphiphiles with controllable configurational diversity, which allows for the customization of chiroptical properties, conformational flexibility and self-assembly.
In-chain poly(phosphonate)s via acyclic diene metathesis polycondensation
Bauer, Kristin N.,Tee, Hisaschi T.,Lieberwirth, Ingo,Wurm, Frederik R.
, p. 3761 - 3768 (2016/06/09)
In-chain poly(phosphonate)s have been prepared via acyclic diene metathesis polymerization of three different monomers. Novel unsaturated phosphonate monomers with asymmetric structure have been developed. The monomers are accessible via a three-step synthesis that can be easily scaled up. This is the first report on poly(phosphonate)s by olefin metathesis where the stable carbon-phosphorus linkage is localized in the polymer backbone. This changes the nature of the degradation products compared to other poly(phosphoester)s. Polymers with molecular weights up to 31000 g mol-1 can be achieved and have been characterized in detail NMR spectroscopy, size exclusion chromatography, thermogravimetry, and differential scanning calorimetry. They have been also compared to structural analogues polyphosphates with respect to crystallization (SAXS, WAXS) and their rheological behavior. Also, solution grown crystals were analyzed rendering some of the herein reported poly(phosphonate)s as interesting defect poly(ethylene)-like structures.
Copper-catalyzed trifluoromethylthiolation of primary and secondary alkylboronic acids
Shao, Xinxin,Liu, Tianfei,Lu, Long,Shen, Qilong
supporting information, p. 4738 - 4741 (2015/04/27)
A Cu-catalyzed trifluoromethylthiolation of primary and secondary alkylboronic acids with an electrophilic trifluoromethylthiolating reagent is described. Tolerance for a variety of functional groups was observed.
Phosphate transport inhibitors
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Page/Page column 10, (2010/02/05)
Disclosed is a phosphate transport inhibiting compound represented by Structural Formula (I): R1 and R2 are independently —H, an electron withdrawing group or a C1-C10 alkyl group. Y is a covalent bond, a substituted methylene group, an unsubstituted methylene group or —CR1R2P(O)(OH)—. R3 is a hydrocarbyl group optionally comprising one or more amine, ammonium, ether, thioether or phenylene linking groups, a substituted hydrocarbyl group optionally comprising one or more amine, ammonium, ether, thioether or phenylene linking groups, a heteroaryl group, a substituted heteroaryl group or a phenyl group substituted with one or more groups selected from —Cl, —Br, —F, —CN, —NO2, —ORa, —N(Ra)2, —COORa, —CON(Ra)2, —CORa, —S(O)Ra, —S(O)2Ra, —S(O)2N(Ra)2, —NRaS(O)2Ra, —NRaCORa, a halogenated lower alkyl group, an aryl group, a substituted aryl group, or a halogenated alkoxy group. Each Ra is independently —H, lower alkyl, substituted lower alkyl, aryl or substituted aryl. Each Rb is independently —H, a lower alkyl group, or a phosphate protecting group.
Synthesis of Various New Nitroxide Free Radical Fatty Acids
Hideg, Kalman,Lex, Laszlo
, p. 1431 - 1438 (2007/10/02)
A generally applicable method is presented for the synthesis of various new nitroxide fatty acid isomers in which the fatty acid chains are attached at different positions of the pyrrolidin-1-oxyl ring.These isomers can be obtained by Michael addition of a nitroalkane to an α,β-unsaturated ketone to give a γ-nitro ketone, followed by ring closure with zinc and ammonium chloride to give a 1-pyrroline N-oxide which then reacts with Grignard reagents to give a pyrrolidin-1-oxyl free radical compound, which undergoes phase transfer oxidation of its terminal unsaturated bond.
