Tag: M.W=700-800

Amirkhanov, Nariman V. published the artcileImaging Human Pancreatic Cancer Xenografts by Targeting Mutant KRAS2 mRNA with [111In]DOTAn-Poly(diamidopropanoyl)m-KRAS2 PNA-d(Cys-Ser-Lys-Cys) Nanoparticles, Recommanded Product: 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, the publication is Bioconjugate Chemistry (2010), 21(4), 731-740, database is CAplus and MEDLINE.

95% Of patients with ductal pancreatic cancer carry 12th codon activating mutations in their KRAS2 oncogenes. Early whole body imaging of mutant KRAS2 mRNA activation in pancreatic cancer would contribute to disease management. Scintigraphic hybridization probes to visualize gene activity in vivo constitute a new paradigm in mol. imaging. We have previously imaged mutant KRAS2 mRNA activation in pancreatic cancer xenografts by positron emission tomog. (PET) based on a single radiometal, ⁶⁴Cu, chelated to a 1,4,7,10-tetra(carboxymethylaza)cyclododecane (DOTA) chelator, connected via a flexible, hydrophilic spacer, aminoethoxyethoxyacetate (AEEA), to the N-terminus of a mutant KRAS2 peptide nucleic acid (PNA) hybridization probe. A peptide analog of insulin-like growth factor 1 (IGF1), connected to a C-terminal AEEA, enabled receptor-mediated endocytosis. We hypothesized that a polydiamidopropanoyl (PDAP) dendrimer (generation m), with increasing numbers (n) of DOTA chelators, extended via an N-terminal AEEA from a mutant KRAS2 PNA with a C-terminal AEEA and IGF1 analog could enable more intense external imaging of pancreatic cancer xenografts that overexpress IGF1 receptor and mutant KRAS2 mRNA. ([¹¹¹In]DOTA-AEEA)_n-PDAP^m-AEEA₂-KRAS2 PNA-AEEA-IGF1 analogs were prepared and administered i.v. into immunocompromised mice bearing human AsPC1 (G12D) pancreatic cancer xenografts. CAPAN2 (G12 V) pancreatic cancer xenografts served as a cellular KRAS2 mismatch control. Scintigraphic tumor/muscle image intensity ratios for complementary [¹¹¹In]_n-PDAP^m-KRAS2 G12D probes increased from 3.1 ± 0.2 at n = 2, m = 1, to 4.1 ± 0.3 at n = 8, m = 3, to 6.2 ± 0.4 at n = 16, m = 4, in AsPC1 (G12D) xenografts. Single mismatch [¹¹¹In]_n-PDAP^m-KRAS2 G12 V control probes showed lower tumor/muscle ratios (3.0 ± 0.6 at n = 2, m = 1, 2.6 ± 0.9 at n = 8, m = 3, and 3.7 ± 0.3 at n = 16, m = 4). The mismatch results were comparable to the PNA-free [¹¹¹In]DOTA control results. Simultaneous administration of nonradioactive Gd_n-KRAS2 G12 V probes (n = 2 or 8) increased accumulation of [¹¹¹In]₈KRAS2 G12 V probes 3-6-fold in pancreatic cancer CAPAN2 xenografts and other tissues, except for a 2-fold decrease in the kidneys. As a result, tissue distribution tumor/muscle ratios of ¹¹¹In uptake increased from 3.1 ± 0.5 to 6.5 ± 1.0, and the kidney/tumor ratio of ¹¹¹In uptake decreased by more than 5-fold from 174.8 ± 17.5 to 30.8 ± 3.1. Thus, PDAP dendrimers with up to 16 DOTA chelators attached to PNA-IGF1 analogs, as well as simultaneous administration of the elevated dose of nonradioactive Gd_n-KRAS2 G12 V probes, enhanced tumor uptake of [¹¹¹In]_nKRAS2 PNA probes. These results also imply that Gd(III) dendrimeric hybridization probes might be suitable for magnetic resonance imaging of gene expression in tumors, because the higher generations of the dendrimers, including the NMR contrast Gd_n-KRAS2 G12 V probes, improved tumor accumulation of the probes and specificity of tumor imaging.

Bioconjugate Chemistry published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Recommanded Product: 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Lu, Xiao-Wei published the artcileModulating the hybridization property of PNA with a peptoid-like side chain, Quality Control of 186046-83-3, the publication is Organic Letters (2009), 11(11), 2329-2332, database is CAplus and MEDLINE.

Modification on the γ-N of the PNA backbone yielded a PNA analog with a peptoid-like side chain. We found that the length of the side chain was important in influencing the hybridization affinity of the modified PNA.

Organic Letters published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Quality Control of 186046-83-3.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Shemesh, Yossi published the artcilePNA-Rose Bengal Conjugates as Efficient DNA Photomodulators, SDS of cas: 186046-83-3, the publication is Bioconjugate Chemistry (2015), 26(9), 1916-1922, database is CAplus and MEDLINE.

Selective photoinduced modulation of DNA may provide a powerful therapeutic tool allowing spatial and temporal control of the photochem. reaction. We have explored the photoreactivity of peptide nucleic acid (PNA) conjugates that were conjugated to a highly potent photosensitizer, Rose Bengal (RB). In addition, a short PEGylated peptide (K-PEG₈-K) was conjugated to the C-terminus of the PNA to improve its water solubility A short irradiation (visible light) of PNA conjugates with a synthetic DNA resulted in highly efficient photomodulation of the DNA as evidenced by polyacrylamide gel electrophoresis (PAGE). In addition, a PNA-RB conjugate replacing K-PEG₈-K with four L-glutamic acids (E₄) was found to be photoinactive. Irradiation of active PNA-RB conjugates with synthetic DNA in D₂0 augments the photoactivity; supporting the involvement of singlet oxygen. PAGE, HPLC, and MALDI-TOF analyses indicate that PNA-DNA photo-crosslinking is a significant pathway in the observed photoreactivity. Selective photo-crosslinking of such PNA-RB conjugates may be a novel approach to selective photodynamic therapy (sPDT) as such mols. would be sequence-specific, cell-permeable, and photoactivated in the visible region.

Bioconjugate Chemistry published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C13H16O2, SDS of cas: 186046-83-3.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Berger, Or published the artcileSpectral Transition in Bio-Inspired Self-Assembled Peptide Nucleic Acid Photonic Crystals, Quality Control of 186046-83-3, the publication is Advanced Materials (Weinheim, Germany) (2016), 28(11), 2195-2200, database is CAplus and MEDLINE.

Guanine-containing short sequences of peptide nucleic acids (PNAs), synthetic nucleic acid analogs with an amide backbone, can self-assemble into ordered structures with unique optical properties. These observations prompted examination as to whether PNA monomers can also undergo a process of self-association and organization into supramol. assemblies, as it had previously been shown that even a single amino acid can self-assemble into fibrils with well-ordered electron diffraction. The 4 PNA monomers were tested for their ability to self-assemble into ordered structures under a variety of conditions including organic solvents (MeOH, EtOH, DMSO, and hexafluoro-2-propanol) and diverse buffer solutions with a range of pH values and concentrations The monomers were examined with or without the addnl. protecting groups, fluorenylmethyloxycarbonyl (Fmoc) and benzhydryloxycarbonyl (Bhoc), which are conjugated to the building blocks used for solid phase synthesis of PNA oligomers. Assembly into ordered structures was evident solely for N-(N-Fmoc-2-aminoethyl)-N-[(N-6-Bhoc-9-guanyl)acetyl]glycine (Fmoc-G-(Bhoc)-aeg-OH) in H₂O. Aromatic protecting groups are known to promote self-assembly of short peptides. The Fmoc moiety has a significant impact on the assembly of aromatic peptide amphiphiles. The PNA monomers could be considered as amphiphiles with the protecting groups serving as lipophilic moieties and the guanine base as the hydrophilic component.

Advanced Materials (Weinheim, Germany) published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Quality Control of 186046-83-3.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Schneggenburger, Philipp E. published the artcileAzide reduction during peptide cleavage from solid support-the choice of thioscavenger?, Application In Synthesis of 186046-83-3, the publication is Journal of Peptide Science (2010), 16(1), 10-14, database is CAplus and MEDLINE.

Peptide azides acquired growing impact because of application in bioconjugation via click chem.’ or Staudinger ligation. Furthermore, there are many methods established in organic synthesis addressing the reduction of azides to amines, but no observation of a reductive transformation of peptide azides during SPPS cleavage was yet reported. In the present study, the reduction of peptide azides during SPPS cleavage was investigated depending on the choice of thioscavenger, reacting as reductive species. First observed for short PNA/peptide conjugates the occurring extensive side reaction was also validated for one of the applied azide amino acid building blocks and was further investigated by applying different cleavage cocktails to a series of peptides varying in hydrophobicity and position of the azide moiety in the oligomer sequence. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.

Journal of Peptide Science published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Application In Synthesis of 186046-83-3.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Nim-anussornkul, Duangrat published the artcileSynthesis and optical properties of pyrrolidinyl peptide nucleic acid bearing a base discriminating fluorescence nucleobase 8-(pyrene-1-yl)-ethynyladenine, Recommanded Product: 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, the publication is Bioorganic & Medicinal Chemistry (2017), 25(24), 6388-6397, database is CAplus and MEDLINE.

A combination of fluorophore and nucleobase through a π-conjugated rigid linker integrates the base pairing and the fluorescence change into a single event. Such base discriminating fluorophore can change its fluorescence as a direct response to the base pairing event and therefore have advantages over tethered labels or base surrogates lacking the hydrogen-bonding ability. 8-(Pyrene-1-yl)ethynyl-adenine (A^PyE) has been extensively used as fluorescence labels in DNA and LNA, but it showed little discrimination between different nucleobases. Herein we investigated the synthesis, base pairing ability and optical properties of A^PyE in pyrrolidinyl peptide nucleic acid – a DNA mimic that shows much stronger affinity and specificity towards DNA than natural oligonucleotides. The A^PyE in PNA pairs specifically with thymine in the DNA strand, and resulted in 1.5-5.2-fold enhanced and blue-shifted fluorescence emission. Fluorescence quenching was observed in the presence of mismatched base or abasic site directly opposite to the A^PyE. The behavior of A^PyE in acpcPNA is distinctively different from DNA whereby a fluorescence was increased selectively upon duplex formation with complementary DNA and therefore emphasizing the unique advantages of using PNA as alternative oligonucleotide probes. Applications as color-shifting probe for detection of trinucleotide repeats in DNA were demonstrated, and the performance of the probe was further improved by combination with reduced graphene oxide as an external nano-quencher.

Bioorganic & Medicinal Chemistry published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Recommanded Product: 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Michaelis, Julia published the artcileDNA-Triggered Dye Transfer on a Quantum Dot, Safety of 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, the publication is Bioconjugate Chemistry (2014), 25(1), 18-23, database is CAplus and MEDLINE.

Nucleic acid-templated reactions are frequently explored tools in nucleic acid diagnosis. To enable a separation-free DNA detection, the reactive probe mols. require conjugation with reporter groups that provide measurable changes of an observable parameter upon reaction. A widely used, generic read-out method is based on fluorescence resonance energy transfer (FRET) between two appended dyes. Yet, spectral cross-talk usually limits the achievable enhancements of the FRET signal in DNA-directed chemistries. We describe a DNA-triggered transfer reaction which provides for strong increases of a fluorescent signal caused by FRET. The method may involve DNA- and PNA-based probes and is based upon a proximity-triggered transfer reaction which leads to the covalent fixation of a fluorescence dye on the surface of a quantum dot (QD). The transfer reaction brings the dye closer to the QD than hybridization alone. The resulting FRET signal is a specific monitor of the reaction and allows efficient discrimination of single base mismatched templates. Of note, the 35-fold increase of the FRET signal is measured at 310 nm apparent Stokes shift and turnover in template provides a means for signal amplification.

Bioconjugate Chemistry published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Safety of 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Beall, Edward published the artcileEffects of the backbone and chemical linker on the molecular conductance of nucleic acid duplexes, Safety of 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, the publication is Journal of the American Chemical Society (2017), 139(19), 6726-6735, database is CAplus and MEDLINE.

Scanning tunneling microscope break junction measurements were used to examine how the mol. conductance of nucleic acids depends on the composition of their backbone and the linker group to the electrodes. Mol. conductances of 10 base-pair-long homoduplexes of DNA, aeg-PNA, γ-PNA, and a heteroduplex of DNA/aeg-PNA with identical nucleobase sequence were measured. The mol. conductance was found to vary by 12-13-fold with the change in backbone. Computational studies showed that the mol. conductance differences between nucleic acids of different backbones correlated with differences in backbone structural flexibility. The mol. conductance was also measured for duplexes connected to the electrode through 2 different linkers, one directly to the backbone and one directly to the nucleobase stack. While the linker caused an order-of-magnitude increase in the overall conductance for a particular duplex, the differences in the elec. conductance with backbone composition were preserved. The highest mol. conductance value(0.06G₀) was measured for aeg-PNA duplexes with a base stack linker. These findings revealed an important new strategy for creating longer and more complex electroactive, nucleic acid assemblies.

Journal of the American Chemical Society published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, Safety of 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Totsingan, Filbert published the artcileHighly selective single nucleotide polymorphism recognition by a chiral (5S) PNA beacon, Computed Properties of 186046-83-3, the publication is Chirality (2008), 21(1), 245-253, database is CAplus and MEDLINE.

A chiral peptide nucleic acid (PNA) beacon containing a C-5 modified monomer based on L-lysine was synthesized. The terminal amino group of the lysine side chain was linked to a spacer for future applications on surfaces. The PNA beacon bears a carboxyfluorescein fluorophore and a dabcyl quencher at opposite ends. The DNA binding properties were compared with those of a homologous PNA beacon containing only achiral monomers. Both beacons underwent a fluorescence increase in the presence of complementary DNA, with higher efficiency and higher selectivity (evaluated using single mismatched DNA sequences) observed for the chiral monomer containing PNA. Ion exchange (IE) HPLC with fluorimetric detection was used in combination with the beacon for the selective detection of complementary DNA. A fluorescent peak corresponding to the PNA beacon:DNA duplex was observed at a very low detection limit (1 nM). The discriminating capacity of the chiral PNA beacon for a single mismatch was found to be superior to those observed with the unmodified one, thus confirming the potency of chirality for increasing the affinity and specificity of DNA recognition.

Chirality published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C13H18N2, Computed Properties of 186046-83-3.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics

Gasser, Gilles published the artcileTowards the Preparation of Novel Re/^99mTc Tricarbonyl-Containing Peptide Nucleic Acid Bioconjugates, COA of Formula: C40H35N7O8, the publication is Australian Journal of Chemistry (2011), 64(3), 265-272, database is CAplus.

A novel azido derivative of the di-(2-picolyl)amide (Dpam) ligand, namely 3-azido-N,N-bis-pyridin-2-ylmethylpropionamide (3), was prepared from 3-bromo-N,N-bis(pyridin-2-ylmethyl)propanamide (2) with an excess of sodium azide in DMSO. 3 Was then reacted, by Cu(I)-catalyzed [3+2] cycloaddition (often referred to as click chem.), with the previously reported alkyne-containing peptide nucleic acid (PNA) monomer Fmoc-1-OBu-t to give the Dpam-containing PNA monomer (Fmoc-4-OBu-t) in 44% yield. It was also demonstrated that 3 could be reacted by click chem., on the solid phase, to an alkyne-containing PNA oligomer (alkyne-PNA) to yield Dpam-PNA. The attempts to complex Dpam-PNA with [NEt₄]₂[ReBr₃(CO)₃] and [^99mTc(CO)₃(H₂O)₃]⁺ are also discussed in detail.

Australian Journal of Chemistry published new progress about 186046-83-3. 186046-83-3 belongs to amides-buliding-blocks, auxiliary class Purine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(2-(((benzhydryloxy)carbonyl)amino)-6-oxo-5H-purin-9(6H)-yl)acetamido)acetic acid, and the molecular formula is C40H35N7O8, COA of Formula: C40H35N7O8.

Referemce:
https://en.wikipedia.org/wiki/Amide,
Amide – an overview | ScienceDirect Topics