A photocleavable low molecular weight hydrogel for light-triggered drug delivery
A photocleavable low-molecular-weight hydrogelator (LMWG) was synthesized based on coumarin derivative. 1H NMR and UV spectroscopy study suggested that the gelator had good gelling ability, and the driving force for the gelation were hydrogen bonding and π-π stacking. This molecular hydrogel exhibited satisfied photocleavage at C-N bond in 7-amino coumarin with the light irradiation (365 nm, 77.5 mW/cm2). The promising photo-triggered drug release of antineoplastics cytarabine hydrochloride has been obtained, due to the photocleavage motived gel-sol transition.
Preparation of dual responsive low-molecular-weight hydrogel for long-lasting drug delivery
A novel low-molecular-weight hydrogel (LMWG) was fabricated by oligopeptide and phenylboronic acid to obtain a smart molecular hydrogel with dual glucose and pH response for long-term drug delivery in this study. Dual glucose and pH responsiveness of the blank molecular hydrogel was first evaluated by on-line tracking the dynamics curves using UV spectroscopy. Model drugs of phenformin for antidiabetes and doxorubicin for anticancer were selected to evaluate the drug carry and glucose/pH responsive drug release of the molecular hydrogel. The results showed the drug-loaded LMWG had good sustaining and long-lasting drug delivery in physiological or pathological environment.
Ruthenium-catalyzed α-(hetero)arylation of saturated cyclic amines: Reaction scope and mechanism
Transition-metal-catalyzed sp3 C-H activation has emerged as a powerful approach to functionalize saturated cyclic amines. Our group recently disclosed a direct catalytic arylation reaction of piperidines at the α position to the nitrogen atom. 1-(Pyridin-2-yl)piperidine could be smoothly α-arylated if treated with an arylboronic ester in the presence of a catalytic amount of [Ru3(CO)12] and one equivalent of 3-ethyl-3-pentanol. A systematic study on the substrate and reagent scope of this transformation is disclosed in this paper. The effect of substitution on both the piperidine ring and the arylboronic ester has been investigated. Smaller (pyrrolidine) and larger (azepane) saturated ring systems, as well as benzoannulated derivatives, were found to be compatible substrates with the α-arylation protocol. The successful use of a variety of heteroarylboronic esters as coupling partners further proved the power of this direct functionalization method. Mechanistic studies have allowed for a better understanding of the catalytic cycle of this remarkable transformation featuring an unprecedented direct transmetalation on a RuII-H species. Copyright
Peschiulli, Aldo,Smout, Veerle,Storr, Thomas E.,Mitchell, Emily A.,Elias, Zdenek,Herrebout, Wouter,Berthelot, Didier,Meerpoel, Lieven,Maes, Bert U. W.
supporting information
p. 10378 - 10387
(2013/09/02)
Coil-by-coil assembly of poly[acrylamide-co-3-(methacryl-amido)- phenylboronic acid] with polydiallyldimethyl-ammonium to give alizarin red S responsive films
An electrolyte-stable polymer composite sensor film based on 2.4% boronic acid substituted polyacrylamide (poly[acrylamide-co-3-(methacrylamido)- phenylboronic acid] or P(A-MPBA)) and polydiallyl-dimethyl-ammonium chloride (or PDDACl) is obtained in a coil-by-coil deposition procedure. Based on AFM evidence, the resulting coil aggregate deposits show ca. 5-10 nm diameter and the average film thickness increases with ca. 1 nm per deposition cycle consistent approximately with the solution coil diameter. In electrochemical experiments alizarin red S is employed as a boronic acid indicating redox probe with a Langmuirian binding constant of ca. K = 4 × 106 M -1 and two distinct redox responses tentatively assigned here to two isomeric forms of the complex in oxidized and reduced state. Inter- and intra-coil electron transfer and electron hopping occurs during alizarin red S reduction and back-oxidation. Both smooth and mesoporous ITO substrates are employed. The Royal Society of Chemistry.
Shariki, Sara,Cox, Owen T. L.,Tickell, David A.,Pereira Morais, Marta P.,Van Den Elsen, Jean M. H.,James, Tony D.,Dale, Sara E. C.,Bending, Simon,Marken, Frank
p. 18999 - 19006
(2012/11/07)
Dye displacement assay for saccharide detection with boronate hydrogels
Hydrogel spheres, fashioned from an operationally simple mould, that incorporate boronate units were shown to function as saccharide sensors. The Royal Society of Chemistry.
Ma, Winson M. J.,Pereira Morais, Marta P.,D'Hooge, Fran?ois,Van Den Elsen, Jean M. H.,Cox, Jonathan P. L.,James, Tony D.,Fossey, John S.
supporting information; experimental part
p. 532 - 534
(2009/06/17)
More Articles about upstream products of 220080-93-3