Day: November 21, 2022

Sirci, Francesco published the artcileLigand-, structure- and pharmacophore-based molecular fingerprints: a case study on adenosine A₁, A_2A, A_2B, and A₃ receptor antagonists, Safety of 2-(Furan-2-yl)-7-(2-(4-(4-(2-methoxyethoxy)phenyl)piperazin-1-yl)ethyl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine, the publication is Journal of Computer-Aided Molecular Design (2012), 26(11), 1247-1266, database is CAplus and MEDLINE.

FLAP fingerprints are applied in the ligand-, structure- and pharmacophore-based mode in a case study on antagonists of all four adenosine receptor (AR) subtypes. Structurally diverse antagonist collections with respect to the different ARs were constructed by including binding data to human species only. FLAP models well discriminate “active” (=highly potent) from “inactive” (=weakly potent) AR antagonists, as indicated by enrichment curves, numbers of false positives, and AUC values. For all FLAP modes, model predictivity slightly decreases as follows: A_2BR > A_2AR > A₃R > A₁R antagonists. General performance of FLAP modes in this study is: ligand- > structure- > pharmacophore- based mode. We also compared the FLAP performance with other common ligand- and structure-based fingerprints. Concerning the ligand-based mode, FLAP model performance is superior to ECFP4 and ROCS for all AR subtypes. Although focusing on the early first part of the A_2A, A_2B and A₃ enrichment curves, ECFP4 and ROCS still retain a satisfactory retrieval of actives. FLAP is also superior when comparing the structure-based mode with PLANTS and GOLD. In this study we applied for the first time the novel FLAPPharm tool for pharmacophore generation. Pharmacophore hypotheses, generated with this tool, convincingly match with formerly published data. Finally, we could demonstrate the capability of FLAP models to uncover selectivity aspects although single AR subtype models were not trained for this purpose.

Journal of Computer-Aided Molecular Design published new progress about 377727-87-2. 377727-87-2 belongs to triazoles, auxiliary class GPCR/G Protein,Adenosine Receptor, name is 2-(Furan-2-yl)-7-(2-(4-(4-(2-methoxyethoxy)phenyl)piperazin-1-yl)ethyl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine, and the molecular formula is C8H14O2, Safety of 2-(Furan-2-yl)-7-(2-(4-(4-(2-methoxyethoxy)phenyl)piperazin-1-yl)ethyl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Zhang, Xueli published the artcileA simple, fast and convenient new method for predicting the stability of nitro compounds, Product Details of C2H2N4O2, the publication is Journal of Computer-Aided Molecular Design (2015), 29(5), 471-483, database is CAplus and MEDLINE.

A new method has been proposed to understand and predict the stability of nitro compounds This method uses the maximum electron densities at the critical points of two N-O bonds of nitro groups (ρ_max), and it is more simple and faster than the existing methods and applicable to bigger systems. The correlations between the ρ_max and total energy (E), bond lengths (R_C-NO2, R_N-NO2 and R_O-NO2), bond dissociation energy (BDE), and impact sensitivity (h₅₀) reveal that the mol. stability, which can be reflected by E, R, BDE and h₅₀, generally decreases with the increasing ρ_max. The compound with the larger ρ_max is less stable. For the nitrating reaction, the smaller ρ_max of the product generally implies the easier and faster reaction and the higher occurrence ratio of the product. Therefore, ρ_max can be applied to predict the stability of nitro compounds and the easiness of the nitrating reaction.

Journal of Computer-Aided Molecular Design published new progress about 84406-63-3. 84406-63-3 belongs to triazoles, auxiliary class Triazole,Nitro Compound, name is 4-Nitro-2H-1,2,3-triazole, and the molecular formula is C12H23N3S, Product Details of C2H2N4O2.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Subbaraman, Ram published the artcile4,5-Dicyano-1H-[1,2,3]-Triazole as a Proton Transport Facilitator for Polymer Electrolyte Membrane Fuel Cells, Name: 1H-1,2,3-Triazole-4,5-dicarbonitrile, the publication is Journal of the American Chemical Society (2007), 129(8), 2238-2239, database is CAplus and MEDLINE.

High proton conductivity with limited or no dependence on humidity is the desired property for proton exchange membrane for use in a fuel cell operating >100°. Proton exchange facilitators are designed to aid in transport of protons at low humidity conditions by acting as a proton bridge. The presence of intermol. hydrogen bonding in these compounds gives a proton conducting network where the proton hopping is enabled by the amphoteric nature of these neutral mols. The authors report 4,5-dicyano-1H-[1,2,3]-triazole (DCTz) as an active proton transport facilitator for PEM fuel cells. The authors observe conductivities ∼1 mS/cm in dry conditions at 100° for composites of DCTz with polyacrylonitrile in the absence of any external proton sources. High acidity of N-H proton as well as existence of a hydrogen-bonded network in DCTz leads to facile proton transport through the membrane in the absence of humidity. Diffusion measurements from NMR experiments further confirm the existence of local proton conducting structures over the long range. Electrochem. stability of DCTz in the potential window of interest offers addnl. advantage for the use of this material in PEM fuel cells.

Journal of the American Chemical Society published new progress about 53817-16-6. 53817-16-6 belongs to triazoles, auxiliary class Triazoles, name is 1H-1,2,3-Triazole-4,5-dicarbonitrile, and the molecular formula is C12H19BrS, Name: 1H-1,2,3-Triazole-4,5-dicarbonitrile.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Subbaraman, R. published the artcileTriazole and triazole derivatives as proton transport facilitators in polymer electrolyte membrane fuel cells, SDS of cas: 53817-16-6, the publication is Solid State Ionics (2009), 180(20-22), 1143-1150, database is CAplus.

Some basic aspects pertaining to the application of triazole and its derivatives as proton transport facilitators for membranes for high temperature fuel cell operations are investigated. Performance as proton transport facilitators is studied for compounds in their native solid state and as a dopant in a polymer membrane. Some key parameters which influence the proton transport in the system are the proton affinity, pKa or acidity, activation energy and the ease of formation of hydrogen bonding network. Theor. calculations of the proton affinity of the compounds are presented. The effect of proton affinity of the compound on the activation energies for proton transport is investigated. Proton conductivity is measured for acid doped triazoles in both pellet form (powder triazole mixed with acid) and in composite forms wherein the acid group is contained in a polymer matrix. The effect of formation of a hydrogen bonding network by the triazoles and its impact on the proton conductivity are studied. Also, the effect of ion exchange capacity (IEC) of the host polymeric electrolytes and loading of triazoles in the composites were investigated.

Solid State Ionics published new progress about 53817-16-6. 53817-16-6 belongs to triazoles, auxiliary class Triazoles, name is 1H-1,2,3-Triazole-4,5-dicarbonitrile, and the molecular formula is C14H10N2O, SDS of cas: 53817-16-6.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Subbaraman, R. published the artcileTriazole and triazole derivatives as proton transport facilitators in polymer electrolyte membrane fuel cells, Category: triazoles, the publication is Solid State Ionics (2009), 180(20-22), 1143-1150, database is CAplus.

Some basic aspects pertaining to the application of triazole and its derivatives as proton transport facilitators for membranes for high temperature fuel cell operations are investigated. Performance as proton transport facilitators is studied for compounds in their native solid state and as a dopant in a polymer membrane. Some key parameters which influence the proton transport in the system are the proton affinity, pKa or acidity, activation energy and the ease of formation of hydrogen bonding network. Theor. calculations of the proton affinity of the compounds are presented. The effect of proton affinity of the compound on the activation energies for proton transport is investigated. Proton conductivity is measured for acid doped triazoles in both pellet form (powder triazole mixed with acid) and in composite forms wherein the acid group is contained in a polymer matrix. The effect of formation of a hydrogen bonding network by the triazoles and its impact on the proton conductivity are studied. Also, the effect of ion exchange capacity (IEC) of the host polymeric electrolytes and loading of triazoles in the composites were investigated.

Solid State Ionics published new progress about 14544-45-7. 14544-45-7 belongs to triazoles, auxiliary class Triazoles, name is 5-Nitro-1H-1,2,3-triazole, and the molecular formula is C16H24BF4Ir, Category: triazoles.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Maalouf, M. published the artcileStudy of proton conductivity of triazole-based electrolytes for high temperature fuel cell applications, Recommanded Product: 1H-1,2,3-Triazole-4,5-dicarbonitrile, the publication is ECS Transactions (2010), 25(33), 19-25, database is CAplus.

4,5-Dicyano-1H-[1,2,3]-Triazole (DCTz) is a possible water replacement for proton transport in high temperature polymer electrolyte membranes since it exhibits a favorable proton affinity. In this study, some properties of DCTz doped with Trifluoromethanesulfonic Acid (TFMSA) and Heptadecafluorooctanesulfonic acid (C₈HO₃F₁₇S-HDSA) are investigated. Thermal anal. as well as FTIR data indicated the formation of the salts. After proving to be stable up to 140°C, DCTz, DCTz_TFMSA and DCTz_HDSA salts were formed into membranes in a Polyacrylonitrile (PAN) polymeric binder. Thermogravimetric anal. (TGA) showed that adding the acid increases the stability of the membranes. Electrochem. measurements showed that the acid loading increases the conductivity of these polymeric membranes. Thus, a DCTZ_TFMSA doped PAN membrane has higher conductivity than a DCTZ doped PAN membrane over a temperature range of 20°C to 160°C at low relative humidity (RH). Similarly, increasing the weight % of DCTz_TFMSA in PAN membranes leads to an improved conductivity by an order of magnitude.

ECS Transactions published new progress about 53817-16-6. 53817-16-6 belongs to triazoles, auxiliary class Triazoles, name is 1H-1,2,3-Triazole-4,5-dicarbonitrile, and the molecular formula is C4HN5, Recommanded Product: 1H-1,2,3-Triazole-4,5-dicarbonitrile.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Al-Azmi, Amal published the artcileAlkylation of azoles: synthesis of new heterocyclic-based AT₁-non-peptide angiotensin (II) receptor antagonists, COA of Formula: C4HN5, the publication is Journal of Heterocyclic Chemistry (2007), 44(3), 515-520, database is CAplus.

Several analogs of Losartan (I) were synthesized as potential non-peptide angiotensin (II) receptor antagonists. In these non-peptide analogs, e.g., II, the tetrazole and the substituted imidazole rings of Losartan were replaced, resp., by a carboxylic acid function or its Me ester and substituted triazole, imidazole or benzimidazole moieties. The biphenyl bromide precursor (BPE) used to introduce the linker between the acid/ester function and the heterocyclic moiety was synthesized using Suzuki biphenyl coupling and then incorporated into the target mol. by simple nucleophilic substitution. The fixed N-aryl isomeric forms of several azole and benzimidazole tautomers were successfully separated by HPLC using 50% aqueous acetonitrile as eluent. Intermediate reaction products and final target compounds were fully characterized spectroscopically.

Journal of Heterocyclic Chemistry published new progress about 53817-16-6. 53817-16-6 belongs to triazoles, auxiliary class Triazoles, name is 1H-1,2,3-Triazole-4,5-dicarbonitrile, and the molecular formula is C4HN5, COA of Formula: C4HN5.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Al-Azmi, Amal published the artcileNovel 2H-1,2,3-triazole sodium complex from N-[2-amino-1,2-dicyanovinyl]alkanamides, Category: triazoles, the publication is Heterocycles (2007), 71(10), 2183-2201, database is CAplus.

Diazotization at 0 °C of N-[2-amino-1,2-dicyanovinyl]ethanamide or the propanamide analog prepared from diaminomaleonitrile (DAMN) I using aqueous acetic acid and NaNO₂ solution furnished sodium complex II. The x-ray structure of the complex II showed that it is a 1:1 mixture of the neutral 2H-triazole heterocycle III and its anion deprotonated at the central (N) atom of the ring, together with a sodium counterion and two coordinated water mols. However, when the diazotization reaction was carried out in the presence of aqueous HCl, the product was 5-cyano-2H-[1,2,3]triazole-4-carboxylic acid amide monohydrate III. Diazotization of I using aqueous HCl furnished 1H-1,2,3-triazole-4,5-dicarbonitrile IV, whereas with acetic acid there was no reaction, and hence no route analogous to that leading to complex II. The structure of both complex II and the triazole monohydrate III were solved using x-ray crystallog., and the compounds under study were fully characterized using spectroscopic techniques.

Heterocycles published new progress about 53817-16-6. 53817-16-6 belongs to triazoles, auxiliary class Triazoles, name is 1H-1,2,3-Triazole-4,5-dicarbonitrile, and the molecular formula is C4HN5, Category: triazoles.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Carlsen, Per published the artcileThermal rearrangement of 4-alkyl-1,2,4-triazoles. Rearrangements in the crystalline state, Recommanded Product: 4H-1,2,4-Triazole, the publication is Molecules [Electronic Publication] (1996), 242-250, database is CAplus.

A review and symposium lecture on the thermolyses of 4-alkyl-1,2,4-triazoles with 16 references They were observed to rearrange at 200-350° to the corresponding 1-alkylated triazoles. When substituted in the 4-position with aryl or vinylic substituents, the triazoles were inert to thermolysis, contrary to what was observed for the 4-alkyl- and 4-allyl-substituted systems. The mechanisms for the reactions were elucidated, e.g., by studies of substituent effects and by kinetic measurements in solution as well as for the neat samples. Reactions in solution were slow. The rearrangements in melts of the neat triazoles readily proceeded to the products, and were proposed to take place via a series of nucleophilic displacement steps. X-ray crystallog. measurements of selected structures showed that the interat. distances and angles between the relevant atoms in these structures to a large degree resembled the geometry expected for the S_N2-type transition states proposed for the rearrangement mechanism. Thus, thermolyses of a series of triazole structures at temperatures below their m.ps., confirmed that rearrangements actually did take place. The “kinetics” of the reactions in the crystalline state were investigated, and rate constants and thermodn. data were correlated with the structural characteristics of the crystals.

Molecules [Electronic Publication] published new progress about 63598-71-0. 63598-71-0 belongs to triazoles, auxiliary class Triazole, name is 4H-1,2,4-Triazole, and the molecular formula is C2H3N3, Recommanded Product: 4H-1,2,4-Triazole.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Eddy, Matthew T. published the artcileExtrinsic Tryptophans as NMR Probes of Allosteric Coupling in Membrane Proteins: Application to the A_2A Adenosine Receptor, HPLC of Formula: 377727-87-2, the publication is Journal of the American Chemical Society (2018), 140(26), 8228-8235, database is CAplus and MEDLINE.

Tryptophan indole ¹⁵N-¹H signals are well separated in NMR spectra of proteins. Assignment of the indole ¹⁵N-¹H signals therefore enables one to obtain site-specific information on complex proteins in supramacromol. systems, even when extensive assignment of backbone ¹⁵N-¹H resonances is challenging. Here the authors exploit the unique indole ¹⁵N-¹H chem. shift by introducing extrinsic tryptophan reporter residues at judiciously chosen locations in a membrane protein for increased coverage of structure and function by NMR. The authors demonstrate this approach with three variants of the human A_2A adenosine receptor (A_2AAR), a class A G protein-coupled receptor, each containing a single extrinsic tryptophan near the receptor intracellular surface, in helix V, VI, or VII, resp. The authors show that the native A_2AAR global protein fold and ligand binding activity are preserved in these A_2AAR variants. The indole ¹⁵N-¹H signals from the extrinsic tryptophan reporter residues show different responses to variable efficacy of drugs bound to the receptor orthosteric cavity, and the indole ¹⁵N-¹H chem. shift of the tryptophan introduced at the intracellular end of helix VI is sensitive to conformational changes resulting from interactions with a polypeptide from the carboxy terminus of the Gα_S intracellular partner protein. Introducing extrinsic tryptophans into proteins in complex supramol. systems thus opens new avenues for NMR investigations in solution

Journal of the American Chemical Society published new progress about 377727-87-2. 377727-87-2 belongs to triazoles, auxiliary class GPCR/G Protein,Adenosine Receptor, name is 2-(Furan-2-yl)-7-(2-(4-(4-(2-methoxyethoxy)phenyl)piperazin-1-yl)ethyl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine, and the molecular formula is C25H29N9O3, HPLC of Formula: 377727-87-2.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics