Optimization of synthetic route to PNA-T-OH monomers

Peptide nucleic acids are synthetic molecules crafted to mimic natural nucleic acids, and thus, they are widely utilized in many chemical, and, biomedical applications. Although there exist many approaches to synthesize monomers to date, there is still room to improve these methodologies. With this motivation, we compared some widely utilized synthetic routes to obtain N-Boc-PNA-T-OH, and N-Fmoc-PNA-T-OH. Our results indicate that N-Bocethylenediamine is the most pivotal intermediate in the chemistry of PNA, and synthetic route commencing with this material affords these two PNA monomers in relatively high yield, and purity, while being very reproducible

Determination of Enantiomeric Compositions of Analytes Using Novel Fluorescent Chiral Molecular Micelles and Steady State Fluorescence Measurements

Novel fluorescent chiral molecular micelles (FCMMs) were synthesized, characterized, and employed as chiral selectors for enantiomeric recognition of non-fluorescent chiral molecules using steady state fluorescence spectroscopy. The sensitivity of the fluorescence technique allowed for investigation of low concentrations of chiral selector (3.0 x 10(-5) M) and analyte (5.0 x 10(-6) M) to be used in these studies. The chiral interactions of glucose, tartaric acid, and serine in the presence of FCMMs poly(sodium N-undecanoyl-L-tryptophanate) [poly-L-SUW], poly(sodium N-undecanoyl-L-tyrosinate) [poly-L-SUY], and poly(sodium N-undecanoyl-L-phenylalininate) [poly-SUF] were based on diastereomeric complex formation. Poly-L-SUW had a significant fluorescence emission spectral difference as compared to poly-L-SUY and poly-L-SUF for the enantiomeric recognition of glucose, tartaric acid, and serine. Studies with the hydrophobic molecule alpha-pinene suggested that poly-L-SUY and poly-L-SUF had better chiral discrimination ability for hydrophobic analytes as compared to hydrophilic analytes. Partial-least-squares regression modeling (PLS-1) was used to correlate changes in the fluorescence emission spectra of poly-L-SUW due to varying enantiomeric compositions of glucose, tartaric acid, and serine for a set of calibration samples. Validation of the calibration regression models was determined by use of a set of independently prepared samples of the same concentration of chiral selector and analyte with varying enantiomeric composition. Prediction ability was evaluated by use of the root-mean-square percent relative error (RMS%RE) and was found to range from 2.04 to 4.06%

Optimization of synthetic route to PNA-T-OH monomers

Peptide nucleic acids are synthetic molecules crafted to mimic natural nucleic acids, and thus, they are widely utilized in many chemical, and, biomedical applications. Although there exist many approaches to synthesize monomers to date, there is still room to improve these methodologies. With this motivation, we compared some widely utilized synthetic routes to obtain N-Boc-PNA-T-OH, and N-Fmoc-PNA-T-OH. Our results indicate that N-Boc-ethylenediamine is the most pivotal intermediate in the chemistry of PNA, and synthetic route commencing with this material affords these two PNA monomers in relatively high yield, and purity, while being very reproducible

The state of the art in core-shell type lipid polymer hybrid nanocarriers and beyond

The need to enhance the therapeutic effect of drugs and thus reduce their side effects is the reason for the emergence of today\u27s drug delivery systems. With the advent of nanotechnology, numerous molecular structures - from carbon nanotubes to polymeric materials - have been developed, and significant progress has been made. However, all these promising results do not mean that drug delivery systems are a solution to all problems in pharmaceutical technology. This is because any drug delivery system, while having its advantages, also suffers from certain limitations. Therefore, new and hybrid structures are created by combining different materials. In this respect, lipid-polymer hybrid particles emerged as a core-shell structure, where the polymer core is covered with a layer of phospholipids, and have attracted attention in the academic community. This manuscript, which provides an overview of the fundamentals of these molecular architectures, begins with a description of lipid-polymer hybrid particles. Conventional and unconventional production methods for fabricating these structures are then described. This is followed by a section discussing how the physical properties of these particles are characterized and how the physical properties affect pharmaceutical activity. The final section discusses prominent examples from the literature

Optimization of synthetic route to PNA-T-OH monomers

Peptide nucleic acids are synthetic molecules crafted to mimic natural nucleic acids, and thus, they are widely utilized in many chemical, and, biomedical applications. Although there exist many approaches to synthesize monomers to date, there is still room to improve these methodologies. With this motivation, we compared some widely utilized synthetic routes to obtain N-Boc-PNA-T-OH, and N-Fmoc-PNA-T-OH. Our results indicate that N-Bocethylenediamine is the most pivotal intermediate in the chemistry of PNA, and synthetic route commencing with this material affords these two PNA monomers in relatively high yield, and purity, while being very reproducible

The synthesis of peptide-conjugated poly(2-ethyl-2-oxazoline)-b-poly(L-lactide) (PEtOx-b-PLA) polymeric systems through the combination of controlled polymerization techniques and click reactions

To optimize the therapeutic effect of pharmaceutical agents, drug delivery systems tailored from FDA-approved polymers like poly(L-lactide) (PLA) is an effective strategy. Because of their hydrophobic character, these systems greatly suffer from reduced circulation time thus, amphiphilic block copolymers became favorable to overcome this limitation. Of them, poly(oxazoline)-b-poly(L-lactide) are of choice as poly(oxazoline) (PEtOx) is compatible, biodegradable, while exhibiting minimum cytotoxicity. To tailor selective drug targeting drug delivery systems, whereby their selectivity for tumor tissues is maximized, these polymers should be decorated with so-called tumor-homing agents, such as antibodies, peptides and so forth. To this respect, we designed a new block copolymer, allyl-poly(2-ethyl-2-oxazoline)-b-poly(L-lactide) allyl-(PEtOx-b-PLA) and its subsequent conjugation to tumor-homing peptides, peptide-18, and peptide-563 at the terminal position. In this manuscript, we report our synthetic route to obtain this building block and its conjugation to tumor-homing agents

Determination of enantiomeric compositions of analytes using novel fluorescent chiral molecular micelles and steady state fluorescence measurements

Novel fluorescent chiral molecular micelles (FCMMs) were synthesized, characterized, and employed as chiral selectors for enantiomeric recognition of non-fluorescent chiral molecules using steady state fluorescence spectroscopy. The sensitivity of the fluorescence technique allowed for investigation of low concentrations of chiral selector (3.0∈×∈10 -5 M) and analyte (5.0∈×∈10 -6 M) to be used in these studies. The chiral interactions of glucose, tartaric acid, and serine in the presence of FCMMs poly(sodium N-undecanoyl-l-tryptophanate) [poly-l-SUW], poly(sodium N-undecanoyl-l-tyrosinate) [poly-l-SUY], and poly(sodium N-undecanoyl-l- phenylalininate) [poly-SUF] were based on diastereomeric complex formation. Poly-l-SUW had a significant fluorescence emission spectral difference as compared to poly-l-SUY and poly-l-SUF for the enantiomeric recognition of glucose, tartaric acid, and serine. Studies with the hydrophobic molecule α-pinene suggested that poly-l-SUY and poly-l-SUF had better chiral discrimination ability for hydrophobic analytes as compared to hydrophilic analytes. Partial-least-squares regression modeling (PLS-1) was used to correlate changes in the fluorescence emission spectra of poly-l-SUW due to varying enantiomeric compositions of glucose, tartaric acid, and serine for a set of calibration samples. Validation of the calibration regression models was determined by use of a set of independently prepared samples of the same concentration of chiral selector and analyte with varying enantiomeric composition. Prediction ability was evaluated by use of the root-mean-square percent relative error (RMS%RE) and was found to range from 2.04 to 4.06%. © 2007 Springer Science+Business Media, LLC

Design and Synthesis of Novel Peptidomimetics for Cancer Immunotherapy

Tumor cells benefit from some certain signals, which are referred to as “immune checkpoints”, to escape immune-mediated destruction. With that in mind, it is believed that the blockade of these points, such as programmed cell death Ligand-1 (PD-L1) and programmed cell death 1 (PD-1), can restore an adaptative immune response against tumoral cells. In this study, we have designed and synthesized some novel peptidomimetics with a 2-aminobenzathiazole scaffold, which targets the PD-1/PDL-1 pathway. In the viability assay, it was found that these compounds decreased the proliferation of peripheral blood mononuclear cells in the concentration of 10 uM. Overall, our results indicate that these novel compounds are potential checkpoint inhibitors for cancer immunotherapy

Stereochemical and regiochemical trends in the selective detection of saccharides

Several discreet sugar-boronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. In the current investigation, we determine the regio- and stereochemical features of the various equilibrating sugar isomers that induce signal transduction in boronic acid chemosensors such as 1 as well as 2 and 3. We present a unique example of a chemosensor (1) that is selective for ribose, adenosine, nucleotides, nucleosides, and congeners. As a result of this study, we are able to predict and achieve selective fluorescence and colorimetric responses to specific disaccharides as a consequence of their terminal sugar residue linkage patterns and configurations. We also find that the combined use of chemosensors exhibiting complementary reactivities may be used cooperatively to obtain enhanced selectivity for ribose and rare saccharides. © 2006 American Chemical Society