14273-90-6Relevant articles and documents
Synthesis of Tetradecapentaenoic Acid Derivatives
Kolodyazhnaya,Kolodyazhny
, p. 1998 - 2004 (2019)
A 12-stage method for the stereoselective synthesis of tetradecapentaenoic acid derivatives using phosphoric reagents was developed. The key step in the synthesis is the Z-selective Wittig reaction between sorbaldehyde and triphenylphosphonium (6-methoxycarbonyl)hexanilide, as well as the Ramirez-Corey-Fuchs reaction and the Trost-Kazmaier rearrangement. The synthesized (2E,4E,8Z,10E,12E)-N-isobutyltetradeca-2,4,8,10,12-pentaenamide corresponds to a natural compound called γ-Sansho?l.
Solid phase synthesis of liquid crystalline oligopeptides
Cormack, Peter A. G.,Moore, Barry D.,Sherrington, David C.
, p. 353 - 354 (1996)
Structurally well-defined liquid crystalline oligopeptides based upon a side-chain mesogenically substituted L-lysine residue are prepared via solid phase peptide synthesis (SPPS).
Supramolecular assemblies from amphiphilic homopolymers: Testing the scope
Savariar, Elamprakash N.,Aathimanikandan, Sivakumar V.,Thayumanavan
, p. 16224 - 16230 (2006)
It has been shown by us in a recent communication that homopolymers, in which each repeat unit contains a hydrophilic and a hydrophobic head group, are capable of forming environment-dependent micellar or inverse micellar assemblies. A systematic structure-property relationship study is carried out here to test the scope of the design. We show here that the molecular design is indeed broadly applicable and that there is a significant gain in the critical aggregation concentrations of these polymers, as compared to the small molecule counterparts. We also show that the design can be tuned to achieve vesicle-type assemblies, which further expands the repertoire of amphiphilic homopolymers in a variety of areas. Characterizations of these assemblies have been carried out using transmission electron microscopy, dynamic light scattering, static light scattering, and dye incorporation experiments.
PREPARATION OF ANOMERIC PAIRS OF 1-THIOGLYCOSIDES: USE OF ANOMERIZATION CATALYZED BY BORON TRIFLUORIDE
Connolly, Daniel T.,Roseman, Saul,Lee, Yuan C.
, p. 227 - 240 (1980)
Anomeric pairs of some alkyl 1-thioaldopyranosides of D-galactose, D-glucose, D-mannose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, and L-fucose were prepared.The per-O-acetylated, 1,2-trans anomers of 6-(trifluoroacetamido)hexyl 1-thioaldopyranosides and 5-(methoxycarbonyl)pentyl 1-thioaldopyranosides were anomerized with boron trifluoride in dichloromethane.The anomeric mixtures were then separated by chromatography, using columns of either silica gel or an ion-exchange resin.De-blocking of the separated compounds provided pure anomers of 6-aminohexyl 1-thioaldopyranosides or 5-carboxypentyl 1-thioaldopyranosides.The aglycons of the latter glycosides were further extended by reaction with aminoacetaldehyde diethyl acetal, which, after deacetalization of the products, provided an ω-aldehydo group.These series of glycosides could be readily coupled to proteins or solid matrices.
Superacidic porous polymer catalyst and its application in esterification of carboxylic acid
Park, Eun Joo,Bae, Chulsung
, p. 493 - 500 (2017)
Two solid acid catalysts, SAC1 and SAC2, with porous structure obtained from mesoporous hard template were synthesized and characterized by Fourier transform infrared spectroscopy, acid-base titration, nitrogen adsorption/desorption, scanning electron mic
RGD-conjugated two-photon absorbing near-IR emitting fluorescent probes for tumor vasculature imaging
Yue, Xiling,Morales, Alma R.,Githaiga, Grace W.,Woodward, Adam W.,Tang, Simon,Sawada, Junko,Komatsu, Masanobu,Liu, Xuan,Belfield, Kevin D.
, p. 10716 - 10725 (2015)
Observation of the activation and inhibition of angiogenesis processes is important in the progression of cancer. Application of targeting peptides, such as a small peptide that contains adjacent l-arginine (R), glycine (G) and l-aspartic acid (D) residues can afford high selectivity and deep penetration in vessel imaging. To facilitate deep tissue vasculature imaging, probes that can be excited via two-photon absorption (2PA) in the near-infrared (NIR) and subsequently emit in the NIR are essential. In this study, the enhancement of tissue image quality with RGD conjugates was investigated with new NIR-emitting pyranyl fluorophore derivatives in two-photon fluorescence microscopy. Linear and nonlinear photophysical properties of the new probes were comprehensively characterized; significantly the probes exhibited good 2PA over a broad spectral range from 700-1100 nm. Cell and tissue images were then acquired and examined, revealing deep penetration and high contrast with the new pyranyl RGD-conjugates up to 350 μm in tumor tissue.
Synthesis of polysiloxane-based quaternized imidazolium salts with a hydroxy group at the end of alkyl groups
Ichikawa, Tsukasa,Wako, Tsuyoshi,Nemoto, Nobukatsu
, p. 1 - 8 (2016)
A series of polysiloxane derivatives having quaternized imidazolium moieties with hydroxyalkyl groups ([HPImnOH]Xs) (where n is the number of methylene group and X is counter anion) were prepared by quaternization of poly(3-chloropropylmethylsiloxane) (P1) using 1-(ω-hydroxyalkyl)imidazole derivatives (ImnOHs) and anion-exchange reaction using lithium bis(trifluoromethanesulfonyl)imide. Polysiloxane-based quaternized imidazolium salts having hydroxyalkyl groups with chloride anion ([HPImnOH]Cls) were obtained with high quaternization ratio of approximately 100 mol%. The glass transition temperatures (Tgs) of [HPImnOH]Xs were reduced by introducing a hydroxy group at the end of alkyl groups; however, no significant reduction in Tgs was observed by anion exchange from chloride anion to bis(trifluoromethanesulfonyl)imide one (Tf2N-).
A modular approach toward block copolymers
Higley, Mary Nell,Pollino, Joel M.,Hollembeak, Eric,Weck, Marcus
, p. 2946 - 2953 (2005)
A novel methodology for the formation of block copolymers has been developed that combines ring- opening metathesis polymerization (ROMP) with functional chain-transfer agents (CTAs) and self-assembly. Telechelic homopolymers of cyclooctene derivatives en
Polymethylene derivatives of nucleic bases with ω-functional groups: VI. [8-(2-oxocyclohexyl)-9-oxooctyl]pyrimidines as potential inhibitors of pyrimidine phosphorylases
Komissarov,Panova,Kritzyn
, p. 67 - 73 (2008)
New polymethylene derivatives of nucleic bases with β-diketo function in ω-position were prepared by alkylation of uracil, thymine, and cytosine. Their physicochemical properties and effect on the E. coli uridine and thimidine phosphorylases were studied.
Coordination-Mediated Synthesis of Purification-Free Bivalent 99mTc-Labeled Probes for in Vivo Imaging of Saturable System
Taira, Yuichiro,Uehara, Tomoya,Tsuchiya, Masao,Takemori, Hideaki,Mizuno, Yuki,Takahashi, Shiori,Suzuki, Hiroyuki,Hanaoka, Hirofumi,Akizawa, Hiromichi,Arano, Yasushi
, p. 459 - 466 (2018)
In the synthesis of technetium-99m (99mTc) labeled target-specific ligands, the presence of a large excess of unlabeled ligands over 99mTc in the injectate hinders target accumulation of 99mTc-labeled ligands by competing for target molecules. To circumvent the problem, we recently developed a concept of the metal coordination-mediated multivalency, and proved the concept with a 99mTc-labeled trivalent compound [99mTc(CO)3(CN-RGD)3]+. In this study, D-penicillamine (Pen) was selected as a chelating molecule and a cyclic RGDfK peptide was conjugated to Pen via a hexanoic linkage (Pen-Ahx-c(RGDfK)). 99mTc complexation reaction, and the stability, integrin αvβ3 binding affinity, and biodistribution of the 99mTc-labeled probe were investigated to evaluate the applicability of the concept to bivalent probes. 99mTc-[Pen-Ahx-c(RGDfK)]2 was obtained over 95% radiochemical yields under low Pen-Ahx-c(RGDfK) concentration (50 μM). 99mTc-[Pen-Ahx-c(RGDfK)]2 showed approximately 10-times higher integrin αvβ3 binding affinity than the monovalent compounds, Pen-Ahx-c(RGDfK) and c(RGDyV). In biodistribution studies, the tumor accumulation of 99mTc-[Pen-Ahx-c(RGDfK)]2 was decreased to 77% and 43% of HPLC-purified (Pen-Ahx-c(RGDfK)-free) 99mTc-[Pen-Ahx-c(RGDfK)]2 by the presence of 5 nmol of unlabeled Pen-Ahx-c(RGDfK) and Re-[Pen-Ahx-c(RGDfK)]2, respectively. 99mTc-[Pen-Ahx-c(RGDfK)]2 provided tumor image without removing unlabeled ligand, while a 99mTc-labeled monovalent probe prepared from a monovalent ligand could not. These findings indicate the availability of the design concept to prepare 99mTc-labeled bivalent probes with a variety of 99mTc core and other metallic radionuclides of clinical relevance.
