Tag: M.W=350-400

Hedge, Oliver J. published the artcileInvestigation of Self-Emulsifying Drug-Delivery System Interaction with a Biomimetic Membrane under Conditions Relevant to the Small Intestine, Safety of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is small intestine self emulsifying drug delivery system biomimetic membrane.

Self-emulsifying drug-delivery systems (SEDDS) have been extensively shown to increase oral absorption of solvation-limited compounds However, there has been little clin. and com. use of these formulations, in large part because the demonstrated advantages of SEDDS have been outweighed by our inability to precisely predict drug absorption from SEDDS using current in vitro assays. To overcome this limitation and increase the biol. relevancy of in vitro assays, an absorption function can be incorporated using biomimetic membranes. However, the effects that SEDDS have on the integrity of a biomimetic membrane are not known. In this study, a quartz crystal microbalance with dissipation monitoring and total internal reflection fluorescence microscopy were employed as complementary methods to in vitro lipolysis-permeation assays to characterize the interaction of various actively digested SEDDS with a liquescent artificial membrane comprising lecithin in dodecane (LiDo). Observations from surface anal. showed that interactions between the digesting SEDDS and LiDo membrane coincided with inflection points in the digestion profiles. Importantly, no indications of membrane damage could be observed, which was supported by flux profiles of the lipophilic model drug felodipine (FEL) and impermeable marker Lucifer yellow on the basal side of the membrane. There was a correlation between the digestion kinetics of the SEDDS and the flux of FEL, but no clear correlation between solubilization and absorption profiles. Membrane interactions were dependent on the composition of lipids within each SEDDS, with the more digestible lipids leading to more pronounced interactions, but in all cases, the integrity of the membrane was maintained. These insights demonstrate that LiDo membranes are compatible with in vitro lipolysis assays for improving predictions of drug absorption from lipid-based formulations.

Langmuir published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Safety of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Asano, Satoshi published the artcileA new intestinal model for analysis of drug absorption and interactions considering physiological translocation of contents, Application of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, the main research area is midazolam drug absorption interaction intestinal model pharmacotherapy.

Precise prediction of drug absorption is key to the success of new drug development and efficacious pharmacotherapy. In this study, we developed a new absorption model, the advanced translocation model (ATOM), by extending our previous model, the translocation model. ATOM reproduces the translocation of a substance in the intestinal lumen using a partial differential equation with variable dispersion and convection terms to describe natural flow and micromixing within the intestine under not only fasted but also fed conditions. In comparison with ATOM, it was suggested that a conventional absorption model, advanced compartmental absorption and transit model, tends to underestimate micromixing in the upper intestine, and it is difficult to adequately describe movements under the fasted and fed conditions. ATOM explains the observed nonlinear absorption of midazolam successfully, with a minimal number of scaling factors. Furthermore, ATOM considers the apical and basolateral membrane permeabilities of enterocytes sep. and assumes compartmentation of the lamina propria, including blood vessels, to consider intestinal blood flow appropriately. ATOM estimates changes in the intestinal availability caused by drug interaction associated with inhibition of CYP3A and P-glycoprotein in the intestine. Addnl., ATOM can estimate the drug absorption in the fed state considering delayed intestinal drug flow. Therefore, ATOM is a useful tool for the anal. of local pharmacokinetics in the gastrointestinal tract, especially for the estimation of nonlinear drug absorption, which may involve various interactions with intestinal contents or other drugs.

Drug Metabolism & Disposition published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Application of 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Yi, Hanxi published the artcileEvaluation of a modified flow-through method for predictive dissolution and in vitro/in vivo correlations of immediate release and extended release formulations, Category: pyridine-derivatives, the main research area is dissolution modified flow predictive method immediate extended release formulation.

The present study evaluated the ability of a modified flow-through method for predicting in vivo performance of immediate release (IR) and extended release (ER) formulations. In vitro dissolution of two model drugs, paracetamol IR tablets and felodipine ER tablets, was investigated under tuned conditions using the modified flow-through method and compared with the compendial quality control (QC) basket method. The in vivo absorption properties of paracetamol IR tablets and felodipine ER tablets were investigated in healthy volunteers. In vitro-in vivo correlation (IVIVC) anal. was performed based on the obtained in vitro and in vivo data. Our results demonstrated that the compendial QC method was not able to reflect in vivo actual absorption, while satisfactory discriminatory power and comparable in vitro dissolution/in vivo absorption were achieved for both paracetamol IR tablets and felodipine ER tablets by the modified flow-through method. This study indicated that the modified flow-through method is a potential tool to reflect in vivo performance of the IR and ER formulations.

Journal of Nanomaterials published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Abuhassan, Qamar published the artcileStructured solubility behaviour in bioequivalent fasted simulated intestinal fluids, Quality Control of 72509-76-3, the main research area is bioequivalent fasted simulated intestinal fluid solubility.

Drug solubility in intestinal fluid is a key parameter controlling absorption after the administration of a solid oral dosage form. To measure solubility in vitro simulated intestinal fluids have been developed, but there are multiple recipes and the optimum is unknown. This situation creates difficulties during drug discovery and development research. A recent study characterised sampled fasted intestinal fluids using a multidimensional approach to derive nine bioequivalent fasted intestinal media that covered over 90% of the compositional variability. These media have been applied in this study to examine the equilibrium solubility of twenty one exemplar drugs (naproxen, indomethacin, phenytoin, zafirlukast, piroxicam, ibuprofen, mefenamic acid, furosemide, aprepitant, carvedilol, tadalafil, dipyridamole, posaconazole, atazanavir, fenofibrate, felodipine, griseofulvin, probucol, paracetamol, acyclovir and carbamazepine) to determine if consistent solubility behavior was present. The bioequivalent media provide in the majority of cases structured solubility behavior that is consistent with physicochem. properties and previous solubility studies. For the acidic drugs (pKa < 6.3) solubility is controlled by media pH, the profile is identical and consistent and the lowest and highest pH media identify the lowest and highest solubility in over 70% of cases. For weakly acidic (pKa > 8), basic and neutral drugs solubility is controlled by a combination of media pH and total amphiphile concentration (TAC), a consistent solubility behavior is evident but with variation related to individual drug interactions within the media. The lowest and highest pH x TAC media identify the lowest and highest solubility in over 78% of cases. A subset of the latter category consisting of neutral and drugs non-ionised in the media pH range have been identified with a very narrow solubility range, indicating that the impact of the simulated intestinal media on their solubility is minimal. Two drugs probucol and atazanavir exhibit unusual behavior. The study indicates that the use of two appropriate bioequivalent fasted intestinal media from the nine will identify in vitro the maximum and min. solubility boundaries for drugs and due to the media derivation this is probably applicable in vivo. These media could be applied during discovery and development activities to provide a solubility range, which would assist placement of the drug within the BCS/DCS and rationalise drug and formulation decisions.

European Journal of Pharmaceutics and Biopharmaceutics published new progress about Absorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Quality Control of 72509-76-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Zadymova, N. M. published the artcileAdsorption of a Lipophilic Drug, Felodipine, at Different Interfaces, COA of Formula: C18H19Cl2NO4, the main research area is adsorption lipophilic drug felodipine different interface.

In connection with the development of methods for the delivery of lipophilic drugs in a bioavailable form, we have employed an integrated approach to the investigation of the adsorption of an antihypertensive drug, felodipine, at interfaces that simulate the surfaces of different carriers. Isotherms have been plotted for felodipine adsorption from solutions in heptane (C = 2.13 x 10-5 – 4.26 x 10-4 M) at interfaces with water and silver metal, as well as for the compression of drug monolayers formed on a water surface from the heptane solutions The quant. characteristics of the studied felodipine layers have been determined, and their phase state and the most probable conformation of adsorbed drug mols. have been analyzed taking into account the data of mol. dynamics simulations. The phase state of the felodipine layers at the heptane/water interface is adequately described by the van Laar equation. A bilayer is formed at the silver surface. A phase transition from a gaseous state to a liquid-expanded state has been revealed for the felodipine layers.

Colloid Journal published new progress about Adsorption. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, COA of Formula: C18H19Cl2NO4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Alshahrani, Saad M. published the artcileEffect of lutrol F grades (poloxamer) on dissolution of hot-melt extruded Kollidon VA64-felodipine matrices, Application In Synthesis of 72509-76-3, the main research area is felodipine poloxamer lutrol F grade dissolution hot melt extrusion.

The objective of this study was to assess the potential of Lutrol F grades as polymeric surfactants for dissolution enhancement of Kollidon VA64-drug matrixes produced by hot-melt extrusion (HME). The poorly soluble model drug felodipine (FEL) with a medium m.p. was selected for this study. Two different grades of Lutrol F (also called Kolliphor P grades) were added into the HME systems to investigate their influence on the drug-incorporated matrixes. Two grades of Lutrols i.e., Lutrol F 68 (KolliphorP 188) and Lutrol F 127 (KolliphorP 407) were studied as polymeric solubilizers. FEL was mixed with KollidonVA64, with or without LutrolF (alone or in combination) at predetermined amounts which resulted in 8 different formulations. Each blend was melt-extruded at the same extrusion conditions. Differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) analyses were performed to evaluate their physicochem. properties. DSC and PXRD studies suggested the formation of amorphous solid dispersion for all extruded formulations. Dissolution studies revealed that the extrudates with Lutrol F grades exhibited faster and higher release compared to formulations without Lutrol F grades. Formulations with high drug loading, which did not include Lutrol F grades, demonstrated low drug release profiles when compared with the same formulations containing Lutrol F grades. Fourier transform IR (FTIR) studies suggested that a stronger hydrogen bond has occurred between the (-NH) of FEL and (C = O) of the pyrrolidone group in Kollidon VA 64. Overall, these studies suggested the potential of Lutrols in enhancing the dissolution rate of poorly soluble model drug FEL.

Acta Poloniae Pharmaceutica published new progress about Dissolution. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Application In Synthesis of 72509-76-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Bochmann, Esther S. published the artcileMicro-scale solubility assessments and prediction models for active pharmaceutical ingredients in polymeric matrices, Quality Control of 72509-76-3, the main research area is polyvinylpyrrolidone polyvinyl acetate active pharmaceutical ingredient; Amorphous solid dispersion; Bisacodyl (PubChem CID: 2391); Carbamazepine (PubChem CID: 2554); Celecoxib (PubChem CID: 2662); Cilostazol (PubChem CID: 2754); Clozapine (PubChem CID: 2818); Copovidone (PubChem CID: 25086-89-9); Data review; Dipyridamole (PubChem CID: 3108); Felodipine (PubChem CID: 3333); Gliclazide (PubChem CID: 3475); Griseofulvin (PubChem CID: 441140); Indomethacin (PubChem CID: 3715); Itraconazole (PubChem CID: 55283); Lamotrigine (PubChem CID: 3878); Loratadine (PubChem CID: 3957); Naproxen (PubChem CID: 156391); Nifedipine (PubChem CID: 4485); Posaconazole (PubChem CID: 468595); Praziquantel (PubChem CID: 4891); Prediction model; Probucol (PubChem CID: 4912); Ritonavir (PubChem CID: 392622); Solubility; Telmisartan (PubChem CID: 65999); Verapamil-HCl (PubChem CID: 62969).

The number of models for assessing the solubility of active pharmaceutical ingredients (APIs) in polymeric matrixes on the one hand and the extent of available associated data on the other hand has been rising steadily in the past few years. However, according to our knowledge an overview on the methods used for prediction and the resp. exptl. data is missing. Therefore, we compiled exptl. data, the techniques used for their determination and the models used for estimating the solubility Our focus was on polymers commonly used in spray drying and hot-melt extrusion to form amorphous solid dispersions (ASDs), namely polyvinylpyrrolidone grades (PVP), polyvinyl acetate (PVAc), vinylpyrrolidone-vinyl acetate copolymer (copovidone, COP), polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft polymer (Soluplus, SOL), different types of methacrylate copolymers (PMMA), polyethylene glycol grades (PEG) and hydroxypropyl-methylcellulose grades (HPMC). The literature data were further supplemented by our own results. The final data set included 37 APIs and two sugar derivatives The majority of the prediction models was constituted by the m.p. depression method, dissolution endpoint measurements, indirect solubility determination by Tg and the use of low mol. weight analogs. We observed that the API solubility depended more on the working group which conducted the experiments than on the measuring technique used. Furthermore, this compilation should assist researchers in choosing a prediction method suited for their investigations. Furthermore, a statistical assessment using recursive feature elimination was performed to identify descriptors of mols., which are connected to the API solubility in polymeric matrixes. It is capable of predicting the criterium 20% API soluble at 100°C (Yes/No) for an unknown compound with a balanced accuracy of 71%. The identified 8 descriptors to be connected to API solubility in polymeric matrixes were the number of hydrogen bonding donors, three descriptors related to the hydrophobicity of the mol., glass transition temperature, fractional neg. polar van der Waals surface area, out-of-plane potential energy and the fraction of rotatable bonds. Finally, in addition to our own model, the data set should help researchers in training their own solubility prediction models.

European Journal of Pharmaceutics and Biopharmaceutics published new progress about Flexibility. 72509-76-3 belongs to class pyridine-derivatives, name is 3-Ethyl 5-methyl 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C18H19Cl2NO4, Quality Control of 72509-76-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Feibelman, Peter J. published the artcileWhat Limits Turnover Number in NH₃ Synthesis on a PNP Pincer Molecule?, SDS of cas: 338800-13-8, the publication is Comments on Inorganic Chemistry (2014), 34(1-2), 3-16, database is CAplus.

Abiol. NH₃ synthesis under mild conditions on a PNP [=2,6-bis(di-tert-butyl-phosphinomethyl)pyridine] pincer chelating an Mo(N₂)₃ group has been reported and attributed to a catalytic cycle wherein only the equatorial N₂ is reduced. The present calculations suggest that reduction of axial N₂ ligands was the reason the cycle ended after production of 23 equivalent of NH₃. NH₃ detachment from axial NNH₃ initiates a terminal reaction pathway by leaving an axial nitrido N behind on the Mo. The trans influence of the strong axial nitride bond causes the second axial N₂ to detach from the Mo, with N-Mo-N₂ remaining as a non-catalytic, pincer-chelated group.

Comments on Inorganic Chemistry published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C23H43NP2, SDS of cas: 338800-13-8.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Benyettou, Farah published the artcileRedox-Responsive Viologen-Mediated Self-Assembly of CB[7]-Modified Patchy Particles, Formula: C22H18Cl2N2, the publication is Langmuir (2016), 32(28), 7144-7150, database is CAplus and MEDLINE.

Sulfonated surface patches of poly(styrene)-based colloidal particles (CPs) were functionalized with cucurbit[7]uril (CB[7]). The macrocycles served as recognition units for di-Ph viologen (DPV²⁺), a rigid bridging ligand. The addition of DPV²⁺ to aqueous suspensions of the particles triggered the self-assembly of short linear and branched chainlike structures. The self-assembly mechanism is based on hydrophobic/ion-charge interactions that are established between DPV²⁺ and surface-adsorbed CB[7]. DPV²⁺ guides the self-assembly of the CPs by forming a ternary DPV²⁺⊂(CB[7])₂ complex in which the two CB[7] macrocycles are attached to two different particles. Viologen-driven particle assembly was found to be both directional and reversible. Whereas sodium chloride triggers irreversible particle disassembly, the one-electron reduction of DPV²⁺ with sodium dithionite causes disassembly that can be reversed via air oxidation Thus, this bottom-up synthetic supramol. approach allowed for the reversible formation and directional alignment of a 2D colloidal material.

Langmuir published new progress about 47369-00-6. 47369-00-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Benzene,Organic ligands for MOF materials,Nitrogen containing MOF ligands,Nitrogen containing MOF ligands, name is 1,1′-Diphenyl-[4,4′-bipyridine]-1,1′-diium chloride, and the molecular formula is C22H18Cl2N2, Formula: C22H18Cl2N2.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Li, Shuzheng published the artcileVoltammetric study on some electron relays and ligands, Related Products of pyridine-derivatives, the publication is Taiyangneng Xuebao (1983), 4(3), 269-75, database is CAplus.

The voltammetric behavior is described of 2,2′-bipyridine; 4,4′-bipyridine and their derivative of small mols. and macromols. at pH 2-10. From the viewpoint of selecting an electron relay, these results are discussed, including the generation of H in the photoreduction system of H₂O with Ru (bipy)₃²⁺ as sensitizer. Finally, the voltammetric behavior and redox potentials of these compounds are explained.

Taiyangneng Xuebao published new progress about 47369-00-6. 47369-00-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Benzene,Organic ligands for MOF materials,Nitrogen containing MOF ligands,Nitrogen containing MOF ligands, name is 1,1′-Diphenyl-[4,4′-bipyridine]-1,1′-diium chloride, and the molecular formula is C22H18Cl2N2, Related Products of pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem