1510-21-0Relevant articles and documents
Cholesterol-linked β-cyclodextrin - A thermotropic liquid-crystalline derivative
Shaikh, Vasi Ahmed Ebrahim,Lonikar, Shrikant Vitthal,Dhobale, Deepa Arun,Pawar
, p. 1975 - 1980 (2007)
Liquid-crystalline derivative of β-cyclodextrin (BCD) was prepared by covalent linking of monocholesteryl succinate (ChMS) with β-cyclodextrin. To the best of our knowledge, this was first ever attempt so far of its kind, in which BCD has been converted into its liquid-crystalline derivative through covalent linkage of a mesogen. The degree of substitution (DS) obtained was ≈2.00. The product was characterized by various techniques, such as FT-IR, NMR, DSC, hot-stage-coupled optical polarizing microscopy (OPM), microanalysis and chemical methods. Cholesterol-linked β-cyclodextrin (CDCh) derivative was found to exhibit thermotropic liquid-crystalline behavior. The product exhibited birefringence during first heating above 130°C, and it became isotropic at about 180°C, whereas the parent compound BCD decomposed without melting above 250 °C. A comparison of CDCh derivative to similar liquid-crystalline poly-saccharide derivatives is presented.
Poly(N-propargylamide)s bearing cholesteryl moieties: Preparation and optical activity
Zhang, Chaohong,Liu, Dong,Zhou, Bolin,Deng, Jianping,Yang, Wantai
, p. 832 - 838 (2012)
We synthesized a novel chiral cholesteryl-based N-propargylamide (M ch, HCCCH2NHCOCH2CH2COOch, ch = cholesteryl) from which homopolymers [P(Mch)] with different molecular weights (number-average molecular weight: 8600, 14100 and 30000) were prepared. The polymers formed helical structures with a preferential helicity. The three polymers increased in both helix content and specific rotation as the molecular weight increased. P(Mch)-8600 was studied in detail as the model polymer. P(Mch)-8600 adopted helical conformations in toluene, THF, CHCl3 and CH2Cl2, exhibited thermal stability with a decomposition temperature of 273°C and formed a lyotropic liquid crystal under the studied conditions. Copolymers of different compositions of Mch and an achiral monomer (Met) were prepared. The copolymers formed helices to different degrees depending on the specific composition, indicating an effective approach for controlling the formation of helices in synthetic helical polymers.
Matrix-molecule induced chiral enhancement effect of binary supramolecular liquid crystals
Ma, Xiao-Jing,Shen, Yong-Tao,Deng, Ke,Tang, Hong,Lei, Sheng-Bin,Wang, Chen,Yang, Yan-Lian,Feng, Xi-Zeng
, p. 4699 - 4704 (2007)
Chiral enhancement effects associated with supramolecular liquid crystalline structures are studied, using a complex of achiral molecules (4,4′-bipyridine, 4Bpy) and chiral cholesteric liquid crystalline molecules (3-cholesteryloxycarbonylpropanoic acid, C4) as the model system. Non-mesogenic achiral molecule 4Bpy is used as the matrix element. The chiral enhancement of the supramolecular liquid crystalline structures can be revealed by circular dichroism (CD) and helical twisting power measurements. It is interesting that CD spectra of the complex exhibited an appreciably enhanced chiral property in comparison with that of the pure chiral cholesteric C4 molecules at room temperature. The helical pitch measurements by the Grandjean-Cano method also confirm the chiral enhancement effect. In addition, polarizing optical microscopy (POM) measurements indicate that the addition of matrix molecules leads to the explicit expression of the chiral liquid crystalline texture, i.e. twisted grain boundary (TGBA*) phase, at the liquid crystal temperature. Differential scanning calorimetry (DSC) and variable-temperature X-ray diffraction measurements further confirm the existence of the TGBA* phase. The binary supramolecular assembly structures are investigated by scanning tunneling microscope (STM) and the formation of hydrogen bonds between the chiral mesogens and the achiral matrix molecules can be directly observed. The variable-temperature Fourier transform infrared (FTIR) results further demonstrate that the hydrogen bonds persist until 168 °C. These results indicate that the introduction of a bifunctional aromatic base such as bipyridine could lead to self-assembled supramolecular architectures with discernible enhancements of chiral properties. The Royal Society of Chemistry.
Synthesis of novel thiol-reactive amphiphilic lipids based on cholesterol for protein-liposome coupling
Kley, Joerg T.,Fichert, Thomas,Massing, Ulrich
, p. 319 - 327 (1998)
The synthesis of a series of coupling lipids designed for covalently linking proteins to liposomes is described. The new compounds have in common a cholesterylsuccinyl unit as a lipid anchor and a thiol-reactive maleimidobenzoyl unit which are linked by alkyl or (poly)ethylene glycol spacers that differ in length and polarity.
Synthesis of α-carboranyl-α-acyloxy-amides as potential BNCT agents
Jonnalagadda, Subash C.,Cruz, Jonathan S.,Connell, Ryan J.,Scott, Patricia M.,Mereddy, Venkatram R.
, p. 4314 - 4317 (2009)
Novel α-carboranyl-α-acyloxy-amides were prepared as potential BNCT agents utilizing three-component Passerini reaction. Preliminary cytotoxicity of the representative compounds on two brain tumor cell lines (U-87 and A-172) showed no effect on cell viability; an essential requirement for utility as potential BNCT agents.
Electrical conformational bistability of dimesogen molecules with a molecular chord structure
Yang, Yan-Lian,Chan, Qi-Lin,Ma, Xiao-Jing,Deng, Ke,Shen, Yong-Tao,Feng, Xi-Zeng,Wang, Chen
, p. 6889 - 6893 (2006)
Touching a chord: A field-dependent conformational change occurs in dimesogen molecules with flexible linking chains, which illustrates a molecular chord structure that is switchable by an electric field (see picture; HOPG = highly oriented pyrolytic graphite). No discernible changes are observed for dimesogen molecules with rigid linkers. (Figure Presented).
Physico-chemical interactions of a new rod-coil-rod polymer with liposomal system: Approaches to applications in tryptophan-related therapies
Cardoso dos Santos, Marinalva,Silva de Farias, Bruna,da Costa Cabrera, Diego,Roberto Sant'Anna Cadaval Junior, Tito,Antonio de Almeida Pinto, Luiz,Gon?alves Dal-Bó, Alexandre,de Lima, Vania Rodrigues
, (2021)
This work describes the synthesis of the new supramolecular rod-coil-rod polymer, designated as cholesterol-PEO1000-tryptophan (Chl-PEO-Trp), as well as its effects on the physico-chemical properties of phosphatidylcholine (PC)-based liposomes. The molecular interactions between the Chl-PEO-Trp and PC were characterized by HATR-FTIR, DSC, NMR, DLS and zeta (ζ) potential techniques. The Chl-PEO-Trp polymer yield was 75 %. FTIR and DSC data showed that the motion of almost all PC groups was restricted by the polymer, and it promoted a decrease of the trans-gauche isomerization of the PC methylene, restricting the mobility of the hydrophobic region of the liposomes. NMR analyses indicated a Chl-PEO-Trp-induced restriction in the rotation of the PC phosphorus and a discreet increase of the hydrogen mobility of the choline. Despite this increase in the rotation of the choline, DLS and ζ-potential analyses suggested a reorientation of the choline group toward the system surface, which contributed, along with the other physico-chemical effects, to a globally packed membrane arrangement and reduced liposome size. Data described in this work were correlated to possible applications of the Chl-PEO-Trp in its free or PC liposome-loaded forms in the diagnosis and therapy of cancer, SARS caused by coronaviruses, and central nervous system-related diseases.
Cathepsin B-sensitive cholesteryl hemisuccinate-gemcitabine prodrug nanoparticles: Enhanced cellular uptake and intracellular drug controlled release
Xu, Yanyun,Geng, Jianqi,An, Ping,Xu, Yan,Huang, Jin,Lu, Wei,Liu, Shiyuan,Yu, Jiahui
, p. 6985 - 6992 (2015)
Gemcitabine [2′,2′-difluoro-2′-deoxycytidine (dFdC)], firstline treatment for pancreatic cancer in the clinic, is a cytotoxic nucleoside analogue. Nucleoside transporters are required in the transport of gemcitabine into cells since it is a hydrophilic compound. Actually, there are significant drawbacks for the application of gemcitabine in clinic, including a short half-life and serious side effects. In order to overcome the mentioned drawbacks, a novel prodrug, cholesteryl hemisuccinate-gemcitabine (CHSdFdC), was synthesized through covalently coupling the amino group of gemcitabine with the carboxylic group of cholesteryl hemisuccinate. The amphiphilic prodrug self-assembled spontaneously as nanoparticles in aqueous media confirmed by transmission electron microscopy (TEM). Dynamic light scattering (DLS) measurement revealed that the mean particle size is approximately 200 nm in aqueous media. The CHSdFdC nanoparticles displayed accumulative controlled drug release in simulated lysosome conditions (pH 5.0 NaAc buffer solution containing cathepsin B); the amount of drug release reached up to 80% within 10 h. However, there was almost no drug release in pH 7.4 PBS and pH 5.0 NaAc buffer solutions without cathepsin B. All these results indicated the intracellularly controlled drug release manner of the CHSdFdC nanoparticles. The controlled release of dFdC from the CHSdFdC nanoparticles was related closely to cleavage of amide bonds by cathepsin B. The CHSdFdC nanoparticles exhibited increased ability to inhibit cell growth compared with gemcitabine in vitro. Meanwhile, the CHSdFdC nanoparticles exhibited enhanced cellular uptake ability against Bxpc-3 cells, and the amount of CHSdFdC was about 15 fold of gemcitabine during the 2.5 h incubation. All these results showed that the CHSdFdC nanoparticle prodrug has great potential in the treatment of pancreatic cancer.
Chol-Dex nanomicelles: Synthesis, characterization and evaluation as efficient drug carriers for colon targeting
Goyal, Preeti,singh, Mahak,Kumar, Pradeep,Gupta, Alka
, (2021)
Core-shell structures obtained from amphiphilic molecules on self-assembly in a medium have emerged as an important tool in the area of biomedical sciences. Here, we have synthesized cholesteryl-dextran (Chol-Dex) amphiphiles in sufficiently high yields via conjugation of cholesteryl hemisuccinate to dextran in two different concentrations (5 and 10%). After physicochemical and spectral analysis, the nanomicelles were subjected to size measurements. DLS and TEM confirmed the formation of core-shell type of nanomicelles. Hydrophobic drug-entrapped formulations (Metronidazole and Rifampicin) displayed sustained release behaviour of drugs from them. Sustained release at neutral pH demonstrated usefulness of the non-toxic delivery system for colon specific diseases.
LHRHa aided liposomes targeting to human ovarian tumor cells: Preparation and cellular uptake
Yuan, Wen-Min,Song, Qin-Guo,Zhang, Zhi-Rong,Fu, Yao,Liu, Ji,He, Qin
, p. 434 - 438 (2008)
In this study, a synthetic nonapeptide similar to luteinizing hormone-releasing hormone (LHRHa), the ligand of an extracellular membrane receptor specific to ovarian tumor cells, was selected as targeting moiety and electrically adsorbed to the negatively charged liposomes composed of phos-pholipid and monocholesterolsuccinate. Docetaxel, as the first line chemotherapy for ovarian tumor, was chosen to be encapsulated into the liposomes. And a high encapsulate efficiency (93%) and drug loading efficiency (20%) of liposomes were achieved via central composite design. In order to investigate the targeting efficiency of the drug delivery system, in vitro cell uptake was determined and the results showed an increasing uptake of LHRHa aided liposomes compared to normal ones.
Preparation and application of brain glioma targeting berberine and folic acid modified lipid material
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Paragraph 0009; 0018, (2021/09/21)
The invention discloses preparation and application of a brain glioma targeting berberine and folic acid modified lipid material, and can be used for preparing lipidosome modified by brain glioma targeting Tween 80 coated berberine and folic acid. The liposome surface is coated with Tween 80 and can pass through the blood-brain barrier effectively through receptor-mediated endocytosis after binding with low density lipoprotein receptors to deliver the drug to the brain. In addition, the liposome uses folic acid and berberine to modify brain glioma targeting and mitochondrial targeting capacity of the liposome, and the long chain of polyethylene glycol is introduced to stabilize the liposome. A new thought and a method can be provided for targeted therapy of glioma, and a wide application prospect is provided. pH MDR. The utility model can provide a new idea and a method for targeted therapy of brain glioma.
Folic acid modified liposome complex and its preparation and use (by machine translation)
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Paragraph 0049; 0055; 0056, (2019/06/30)
The present invention relates to folic acid modified liposome complex and its preparation and use, which belongs to the field of medicine. The present invention provides folic acid modified liposome complex, it is composed of the following weight proportion of the raw materials with the: loaded with the BIM - S gene recombinant expression vector 1 parts, folic acid modified liposome 5 more than, wherein said folic acid is modified liposome comprising (2, 3 - dioleoyl - propyl) - trimethylamine, cholesterol, polyethylene glycol - succinimide - cholesterol and folic acid - polyethylene glycol - succinimide - cholesterol prepared of raw materials. The invention also provides the liposome method for preparing the compound and use thereof. The present invention provides of the folic acid modified liposome composition not only can kill the lung cancer cell, can also be through targeting TAM to influence the tumor micro-environment, for clinical treatment of lung cancer provides a new choice of drug use for. (by machine translation)
