69888-86-4Relevant academic research and scientific papers
Hydrophobic myristic acid modified PAMAM dendrimers augment the delivery of tamoxifen to breast cancer cells
Matai, Ishita,Gopinath
, p. 24808 - 24819 (2016)
In the present study, cationic generation 5 polyamido amine (G5 PAMAM) dendrimers were hydrophobically modified by grafting the surface with lipid-like myristic acid (My) tails to augment their potential as a drug delivery vector in vitro. Nuclear magnetic resonance (1H NMR) measurements confirmed the presence of myristic acid tails at the dendrimer periphery (My-g-G5). Tamoxifen (TAM) an estrogen agonist, was entrapped in the My-g-G5 domains to impart them with anticancer properties. Transmission electron microscopy (TEM) observations indicate these My-g-G5/TAM complexes to be around 6-8 nm in size. Further, in vitro drug release studies ascertained the ability of My-g-G5/TAM complexes to release TAM in a sustained fashion under acidic conditions (pH 5.5). Cellular uptake studies revealed lysosomes as the target organelles of these nanocomplexes. MTT assay suggested good cell viability of My-g-G5 dendrimers and strong inhibitory effects of My-g-G5/TAM complexes in MCF-7 (human breast adenocarcinoma, estrogen receptor (ER) positive) cells. Dual fluorescence staining, reactive oxygen species (ROS) generation, cell cycle analysis, field emission scanning electron microscopy (FE-SEM), change in mitochondrial membrane potential (MMP, ΔΨ) and gene expression studies revealed the apoptosis-inducing ability of My-g-G5/TAM in MCF-7 cells. Based on our findings, we present these hydrophobically modified G5 PAMAM dendrimers as prospective nanocarriers for TAM delivery for anticancer applications.
A METHOD FOR MODIFICATION OF PEPTIDES IMMOBILIZED ON A SOLID SUPPORT BY TRACELESS REDUCTIVELY CLEAVABLE LINKER MOLECULES
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Page/Page column 57; 58, (2021/02/12)
The present invention relates to a method for modifying and purifying peptides comprising an immobilizing step, a modification step and a releasing step. In the immobilizing step, a crude linker-tagged peptide L-P is coupled to a solid support yielding an immobilized linker-tagged peptide S-L-P. Subsequently, the immobilized linker-tagged peptide S-L-P is modified with one or more organic molecules yielding an immobilized linker-tagged peptide S-L-mP. Finally, the modified peptide is released via a reduced intermediate RI. The linker molecule is a compound of formula 1, X-Tbb-Vaa-U-Y-Z (1), which can be coupled to a purification resin via the moiety X and to a peptide via the moiety Y under the release of the leaving group Z. T is an optional spacer moiety and V is an optional electron withdrawing moiety. U is an aryl or 5- or 6-membered heteroaryl moiety bound to at least one electron withdrawing moiety V, W or E. The linker is stable under acidic conditions and releases the peptide upon addition of a reducing agent.
Development of small-molecule inhibitors of fatty acyl-AMP and fatty acyl-CoA ligases in Mycobacterium tuberculosis
Aldrich, Courtney C.,Baran, Marzena,Boshoff, Helena I. M.,Fu, Peng,Grimes, Kimberly D.,Sibbald, Paul A.,Wilson, Daniel J.
, (2020/06/29)
Lipid metabolism in Mycobacterium tuberculosis (Mtb) relies on 34 fatty acid adenylating enzymes (FadDs) that can be grouped into two classes: fatty acyl-CoA ligases (FACLs) involved in lipid and cholesterol catabolism and long chain fatty acyl-AMP ligases (FAALs) involved in biosynthesis of the numerous essential and virulence-conferring lipids found in Mtb. The precise biochemical roles of many FACLs remain poorly characterized while the functionally non-redundant FAALs are much better understood. Here we describe the systematic investigation of 5′-O-[N-(alkanoyl)sulfamoyl]adenosine (alkanoyl adenosine monosulfamate, alkanoyl-AMS) analogs as potential multitarget FadD inhibitors for their antitubercular activity and biochemical selectivity towards representative FAAL and FACL enzymes. We identified several potent compounds including 12-azidododecanoyl-AMS 28, 11-phenoxyundecanoyl-AMS 32, and nonyloxyacetyl-AMS 36 with minimum inhibitory concentrations (MICs) against M. tuberculosis ranging from 0.098 to 3.13 μM. Compound 32 was notable for its impressive biochemical selectivity against FAAL28 (apparent Ki = 0.7 μM) versus FACL19 (Ki > 100 μM), and uniform activity against a panel of multidrug and extensively drug-resistant TB strains with MICs ranging from 3.13 to 12.5 μM in minimal (GAST) and rich (7H9) media. The SAR analysis provided valuable insights for further optimization of 32 and also identified limitations to overcome.
MODIFIED RELAXIN POLYPEPTIDES COMPRISING A PHARMACOKINETIC ENHANCER AND USES THEREOF
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Paragraph 0395-0396, (2018/08/25)
The present disclosure generally relates to modified relaxin polypeptides, such as modified human relaxin 2 polypeptides, comprising a non-naturally encoded amino acid which is linked to a pharmacokinetic enhancer, and therapeutic uses of such polypeptides, such as for the treatment of cardiovascular conditions (such as heart failure) and/or conditions relating to fibrosis.
Synthesis and Characterization of Fatty Acid Grafted Chitosan Polymer and Their Nanomicelles for Nonviral Gene Delivery Applications
Sharma, Divya,Singh, Jagdish
, p. 2772 - 2783 (2017/11/20)
The aim of this study was to synthesize and characterize fatty acid-grafted-chitosan (fatty acid-g-CS) polymer and their nanomicelles for use as carriers for gene delivery. CS was hydrophobically modified using saturated fatty acids of increasing fatty acyl chain length. Carbodiimide along with N-hydroxysuccinimide was used for coupling carboxyl group of fatty acids with amine groups of CS. Proton nuclear magnetic resonance and Fourier transform infrared spectroscopy were used to quantify fatty acyl substitution onto CS backbone. The molecular weight distribution of the synthesized polymers was determined using size exclusion high performance liquid chromatography and was found to be in range of the parent CS polymer (~50 kDa). The critical micelle concentration (cmc) of the polymers was determined using pyrene as a fluorescent probe. The cmc was found to decrease with an increase in fatty acyl chain length. The amphiphilic fatty acid-g-CS polymers self-assembled in an aqueous environment to form nanomicelles of ~200 nm particle size and slightly positive net charge due to the cationic nature of free primary amino groups on CS molecule. These polymeric nanomicelles exhibited excellent hemo- and cytocompatibility, as evaluated by in vitro hemolysis and MTT cell viability assay, respectively, and showed superior transfection efficiency compared to unmodified chitosan and naked DNA. The surface of these nanomicelles can be further modified with ligands allowing for selective targeting, enhanced cell binding, and internalization. These nanomicelles can thus be exploited as potential nonviral gene delivery vectors for safe and efficient gene therapy.
Single-stranded nucleic acid molecule for regulating expression of gene having delivering function
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Page/Page column 41, (2017/06/19)
The invention provides a single-stranded nucleic acid capable of inhibiting expression of a target gene having a delivery function. The nucleic acid contains, from the 5′-side to the 3′-side, a 5′-side region (Xc), a linker region (Lx), an inner region (Z), a linker region (Ly) and a 3′-side region (Yc) in this order, wherein the inner region (Z) is constituted by linkage of the inner 5′-side region (X) and the inner 3′-side region (Y), the 5′-side region (Xc) is complementary to the inner 5′-side region (X), the 3′-side region (Yc) is complementary to the inner 3′-side region (Y), at least one of the inner region (Z), the 5′-side region (Xc) and the 3′-side region (Yc) comprises an expression inhibitory sequence that inhibits expression of a target gene, and at least one of the 5′-terminus, the 3′-terminus, the linker region (Lx) and the linker region (Ly) is bound to a bio-related substance.
KRN7000 analogue with antitumor activity and synthetic method thereof
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Paragraph 0024; 0025, (2016/11/02)
The invention provides a KRN7000 analogue with antitumor activity and a synthetic method thereof, wherein the KRN7000 analogue is synthesized by substituting oxygen atoms with sulfur atoms in a galactose sugar ring, and replacing various substituting groups at positions R1 and R2, so that a method for obtaining KRN7000 analogues with better anticancer and antitumor bioactivities and other bioactivities is provided. The method is characterized by comprising the steps as shown in the specification.
A systematic understanding of gelation self-assembly: solvophobically assisted supramolecular gelation via conformational reorientation across amide functionality on a hydrophobically modulated dipeptide based ambidextrous gelator, N-n-acyl-(l)Val-X(OBn), (X = 1,ω-amino acid)
Haldar, Saubhik,Karmakar, Koninika
, p. 66339 - 66354 (2015/08/18)
A systematic investigation on gelation self-assembly has been performed on a hydrophobically modulated dipeptide based ambidextrous gelator, N-n-acyl-(l)Val-X(OBn), (X = 1,ω-amino acid). To elucidate the effect of hydrophobic tuning on gelator architecture towards its gelation self-assembly, three sets of gelators with a common formula: CmH2m+1C(=O)NH(l)Val(C=O)NH-(CH2)n-(C=O)OBn, were synthesized, Set-I includes gelators with n = 2, m = 9, 11, 13, 15, 17, for Set-II it is n = 2, 3, 5, m = 13 and Set-III comprises of two isomeric gelators (n = 2, m = 15; n = 10, m = 7). Gelation has been critically analyzed in various apolar (aromatic and aliphatic) and polar (protic and aprotic) solvents using FESEM, CD, IR, WAXRD and rheological studies. Obtained results reveal that π-π type interaction dictates the primary molecular alignment and positioning of amide functionality across the aliphatic chain which influences the peptidic orientation in parallel (when m > n) or antiparallel (when m gel and yield stress of gel systems increases with m, but for a given m, the trend goes apparently inverse with the increasing n. Circular dichroism (CD) studies suggest an intriguing evidence of non-planarity of amide plane during self-assembly, highlighting the involvement of conformational change taking place during molecular organization towards its gelation. Despite complex nature of solvent-gelator interaction, the effect of H-bonding component of solubility parameters was found to have a significant role on self-assembly. Overall, supramolecular forces acting at specific functionalities encrypted in gelator backbone must overcome the solvation energy with synergic assistance of solvophobic effect towards stabilization of gel-network with optimum gelator backbone conformation for achieving required enthalpic contribution for self-assembly.
Synthesis and biological activities of 5-thio-α-GALCERS
Bi, Jingjing,Wang, Jing,Zhou, Kai,Wang, Yuancheng,Fang, Min,Du, Yuguo
supporting information, p. 476 - 480 (2015/04/27)
NKT cells, a unique subset of T cells that recognizes glycolipid antigens presented by CD1d molecules, are believed to produce key cytokines of both Th1 and Th2 T cells and are thus involved in the control of several types of immune response. As an active glycolipid antigen having α-galactosyl ceramide core structure, KRN7000 showed promising immunostimulation activity and was selected as an anticancer drug candidate for further clinical application. In this report, three new KRN7000 structural analogues were designed and synthesized, in which the ring oxygen of the galactopyranose residue is replaced by a sulfur atom along with the variation on the lipid chain. Their abilities for stimulating mouse NKT cells to produce IFN-γ and IL-4 were evaluated both in vivo and in vitro.
Partial synthesis of ganglioside and lysoganglioside lipoforms as internal standards for MS quantification
Gantner, Martin,Schwarzmann, Günter,Sandhoff, Konrad,Kolter, Thomas
, p. 2692 - 2704 (2015/02/19)
Within recent years, ganglioside patterns have been increasingly analyzed by MS. However, internal standards for calibration are only available for gangliosides GM1, GM2, and GM3. For this reason, we prepared homologous internal standards bearing nonnatural fatty acids of the major mammalian brain gangliosides GM1, GD1a, GD1b, GT1b, and GQ1b, and of the tumor-associated gangliosides GM2 and GD2. The fatty acid moieties were incorporated after selective chemical or enzymatic deacylation of bovine brain gangliosides. For modifi cation of the sphingoid bases, we developed a new synthetic method based on olefi n cross metathesis. This method was used for the preparation of a lyso-GM1 and a lyso-GM2 standard. The total yield of this method was 8.7% for the synthesis of d17:1-lyso-GM1 from d20:1/18:0-GM1 in four steps. The title compounds are currently used as calibration substances for MS quantifi cation and are also suitable for functional studies.
