Search results for "Hydrazide"
showing 10 items of 87 documents
Preparation and molecular structures of N′-(2-heteroarylmethylidene)-3-(3-pyridyl)acrylohydrazides
2018
Abstract The crystal and molecular structures of N′-(2-furylmethylidene)-3-(3-pyridyl)acrylohydrazide and N′-(2-thienylmethylidene)-3-(3-pyridyl)acrylohydrazide are reported, and the influence of the type of the heteroatom on the aromaticity of the aromatic rings is discussed. Both molecules are nearly planar. The geometry of the acrylohydrazide arrangement is comparable to that of homologous compounds. Density functional theory (DFT) calculations were performed in order to analyze the changes in the geometry of the studied compounds in the crystalline state and for the isolated molecule. The most significant changes were observed in the values of the N–N and C–N bond lengths. The harmonic …
CCDC 956724: Experimental Crystal Structure Determination
2013
Related Article: M. O. Plutenko, R. D. Lampeka, M. Haukka and E. Nordlander|2013|Acta Crystallogr.,Sect.E:Struct.Rep.Online|69|o765|doi:10.1107/S1600536813009628
CCDC 914350: Experimental Crystal Structure Determination
2013
Related Article: M.O.Plutenko, R.D.Lampeka, M.Haukka, E.Nordlander|2012|Acta Crystallogr.,Sect.E:Struct.Rep.Online|68|o3381|doi:10.1107/S1600536812045412
A second monoclinic polymorph of 2-(3,5-dimethyl-1H-pyrazol-1-yl)-2-hydroxyimino-N'-[1-(pyridin-2-yl)ethylidene]acetohydrazide
2013
[Introduction] The title compound, C 14 H 16 N 6 O 2 , is a second monoclinic polymorph of 2-[1-(3,5-dimethyl)pyrazolyl]-2-hydroxyimino- N 0 -[1-(2-pyridyl)ethylidene] acetohydrazide, with two crystal- lographically independent molecules per asymmetric unit. The non-planar molecules are chemically equal having similar geometric parameters. The previously reported polymorph [Plutenko et al. (2012). Acta Cryst. E 68 , o3281] was described in space group Cc ( Z = 4). The oxime group and the O atom of the amide group are anti with respect to the C—C bond. In the crystal, molecules are connected by N—H N hydrogen bonds into zigzag chains extending along the b axis. peerReviewed
Polyaspartylhydrazide Copolymer-Based Supramolecular Vesicular Aggregates as Delivery Devices for Anticancer Drugs
2008
In this paper we report on three different hydrophilic copolymers based on alpha,beta-polyaspartylhydrazide (PAHy) bearing butyric groups in the side chain (C 4) (PAHy-C 4) or a combination of butyric groups and positive charged residues ((carboxypropyl)trimethylammonium chloride, CPTACl) (PAHy-C 4-CPTA) that were synthesized and used for the preparation of new supramolecular vesicular aggregates (SVAs) containing gemcitabine as an antitumor drug. Gemcitabine-loaded SVAs containing synthesized PAHy derivatives were characterized from the physicochemical and technological point of view and the in vitro toxicity and anticancer activity on two different human cancer cell lines, i.e., CaCo-2 (h…
Dielectric Behavior of Aqueous Solutions of α,β-Poly(aspartyl hydrazide) and α,β-Poly(N-hydroxyethyl aspartamide): An Investigation of the Structural…
1994
The dielectric properties of aqueous solutions of α,β-poly(aspartyl hydrazide) (PAHy) and of α,β-poly( N-hydroxyethyl aspartamide) (PHEA) were measured at 25 ° C in the frequency range of 100 MHz to 15 GHz using a time domain reflection method (TDR). Single time relaxation processes were found at 2 GHz and 15 GHz, respectively. The low frequency dispersion was inter preted in terms of the dynamics of polymeric segments based on the dielectric relaxation strength and the relaxation time. The high frequency process which is attributed to the rotational relaxation of water, indicated that water mole cules surrounding the polymeric backbone and in the pure state have a similar rotational behav…
Folate-targeted supramolecular vesicular aggregates based on polyaspartyl-hydrazide copolymers for the selective delivery of antitumoral drugs.
2010
Supramolecular vesicular aggregates (SVAs) have the advantage of combining the safe and biocompatible properties of colloidal vesicular carriers based on phospholipids with those of polymeric materials, i.e. polyaspartyl-hydrazide (PAHy) copolymers. To provide SVAs with a certain tumour selectivity, folate moieties were chemically conjugated to PAHy copolymers. Physicochemical properties (mean sizes, polydispersity index and zeta potential) of folate-targeted SVAs (FT-SVAs) loaded with gemcitabine were evaluated. The antiproliferative and anticancer activity of gemcitabine-loaded FT-SVAs was evaluated against two cancer cell lines, i.e. MCF-7 cells which over-express the folate receptor and…
Cationic Supramolecular Vesicular Aggregates for Pulmonary Tissue Selective Delivery in Anticancer Therapy
2016
The biopharmaceutical properties of supramolecular vesicular aggregates (SVAs) were characterized with regard to their physicochemical features and compared with cationic liposomes (CLs). Neutral and cationic SVAs were synthesized using two different copolymers of poly(aspartyl hydrazide) by thin-layer evaporation and extrusion techniques. Both copolymers were self-assembled in pre-formulated liposomes and formed neutral and cationic SVAs. Gemcitabine hydrochloride (GEM) was used as an anticancer drug and loaded by a pH gradient remote loading procedure, which significantly increased drug loading inside the SVAs. The resulting average size of the SVAs was 100 nm. The anticancer activity of …
Novel cationic polyaspartamide with covalently linked carboxypropyl-trimethyl ammonium chloride as a candidate vector for gene delivery
2006
Abstract The non-viral gene vector properties of a protein-like polymer, the α,β-poly(N-2-hydroxyethyl)- d , l -aspartamide (PHEA) were investigated after its derivatization with 3-(carboxypropyl)trimethyl-ammonium chloride (CPTA) as molecule bearing cationic groups, in order to obtain stable polycations able to condense DNA. PHEA was firstly functionalized with hydrazide pendant groups by reaction with hydrazine monohydrate (HYD), obtaining the polyhydrazide α,β-poly(N-2-hydroxyethyl/carbazate)- d , l -aspartamide (PHEA–HYD). In this paper we reported that polymer functionalization degree can be easily modulated by varying reaction conditions, so allowing us to produce two PHEA derivatives…
HYDROGELS OF HYALURONIC ACID AND alpha, beta-POLYASPARTYLHYDRAZIDE AND THEIR BIOMEDICAL AND PHARMACEUTICAL USES
2005
Compositions and products based on the chemical crosslinking of hyaluronic acid with a polyfunctional polymer having a protein-like structure, bearing hydrazido pendent groups along the polymeric chain. The polymer is preferably, alpha-beta-polyaspartylhydrazide, a biocompatible macromolecule. The materials obtained after crosslinking, specifically hydrogels, undergo a reduced chemical and enzymatic degradation, unlike the starting hyaluronic acid, and they can be used to prepare systems for applications in the biomedical and pharmaceutical field.