Tag: M.W=300-350

Dutta, Sansa published the artcileEngineered-membranes and engineered-micelles as efficient tools for purification of halorhodopsin and bacteriorhodopsin, Quality Control of 85618-21-9, the publication is Analyst (Cambridge, United Kingdom) (2015), 140(1), 204-212, database is CAplus and MEDLINE.

We describe two alternative and complementary purification methods for halorhodopsin and bacteriorhodopsin. The first relies on a unique form of detergent micelles which we have called engineered-micelles. These are specifically conjugated in the presence of [hydrophobic chelator:Fe²⁺] complexes and form detergent aggregates into which membrane proteins partition, but hydrophilic water-soluble proteins do not. The approach was tested on the membrane protein, bacteriorhodopsin (bR), with five non-ionic detergents (OG, OTG, NG, DM, and DDM), commonly used in purification and crystallization of membrane proteins, in combination with the com. available bathophenanthroline or with one of the three synthesized phenanthroline derivatives (Phen-C10, Phen-C8 and Phen-C6). Our results show that bR is extracted efficiently (60-86%) and directly from its native membrane into diverse detergent aggregates with preservation of its native conformation, while 90-95% of an artificial contaminating background is excluded. For implementation of the second method, based on engineered-membranes, the use of detergents, which in some cases may produce protein denaturation, is not required at all. Protein-containing membranes are conjugated via the same hydrophobic [chelator:metal ion] complexes but maintain the membrane protein in its native bilayer environment throughout the process. This method is demonstrated on the membrane protein halorhodopsin from Natronomonas pharaonis (phR) and leads to good recovery yields (74-89%) and removal of >85% of artificial background impurities while preserving the native state of phR. The detailed structure of the hydrophobic chelator used has been found to have a marked effect on the purity and yield of both methods.

Analyst (Cambridge, United Kingdom) published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C14H28O5S, Quality Control of 85618-21-9.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Tanaka, Masamichi published the artcileBoronic-Acid-Catalyzed Regioselective and 1,2-cis-Stereoselective Glycosylation of Unprotected Sugar Acceptors via S_Ni-Type Mechanism, Name: (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, the publication is Journal of the American Chemical Society (2018), 140(10), 3644-3651, database is CAplus and MEDLINE.

Regio- and 1,2-cis-stereoselective chem. glycosylation of unprotected glycosyl acceptors has been in great demand for the efficient synthesis of natural glycosides. However, simultaneously regulating these selectivities has been a longstanding problem in synthetic organic chem. In nature, glycosyl transferases catalyze regioselective 1,2-cis-glycosylations via the S_Ni mechanism, yet no useful chem. glycosylations based on this mechanism have been developed. In this paper, we report a highly regio- and 1,2-cis-stereoselective S_Ni-type glycosylation of 1,2-anhydro donors and unprotected sugar acceptors using p-nitrophenylboronic acid (10e) as a catalyst in the presence of water under mild conditions. Highly controlled regio- and 1,2-cis-stereoselectivities were achieved via the combination of boron-mediated carbohydrate recognition and the S_Ni-type mechanism. Mechanistic studies using the KIEs and DFT calculations were consistent with a highly dissociative concerted S_Ni mechanism. This glycosylation method was applied successfully to the direct glycosylation of unprotected natural glycosides and the efficient synthesis of a complex oligosaccharide with minimal protecting groups.

Journal of the American Chemical Society published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C9H9NO6S, Name: (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Aono, Toshiaki published the artcileThe effect of oxygen insulation on the stability of image dyes of a color photographic print and the behavior of alkylhydroquinones as antioxidants, Application of 2,5-Bis(2,4,4-trimethylpentan-2-yl)benzene-1,4-diol, the publication is Journal of Applied Photographic Engineering (1982), 8(5), 227-31, database is CAplus.

Studies concerning the light fading of color prints due to oxidation by O from the ambient atm. are described. From studying the effects of O insulation by various techniques of polymer film lamination, it has been found that O mols., which greatly accelerate the light fading of magenta and yellow dyes in color prints, penetrate most easily through a polyethylene-coated paper support. The acceleration of light fading of the dye image by the migrating O is restrained not only by alkylhydroquinone but also by alkylbenzoquinone, incorporated in the dye image layer. This result can be explained in terms of a photochem. reaction mechanism, namely, alkylbenzoquinone reacts to form alkylhydroquinone derivatives upon exposure to light.

Journal of Applied Photographic Engineering published new progress about 903-19-5. 903-19-5 belongs to alcohols-buliding-blocks, auxiliary class Benzene,Phenol, name is 2,5-Bis(2,4,4-trimethylpentan-2-yl)benzene-1,4-diol, and the molecular formula is C22H38O2, Application of 2,5-Bis(2,4,4-trimethylpentan-2-yl)benzene-1,4-diol.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Kobayashi, Yuka published the artcileLactate sensors based on con A/LOx multilayer-modified electrodes, Related Products of alcohols-buliding-blocks, the publication is Chemical Sensors (1997), 13(Suppl. B), 29-32, database is CAplus.

Proteins multilayers composed of Con A and lactate oxidase (LOx) were prepared on the surface of a platinum electrode to construct electrochem. enzyme sensors sensitive to L-lactate, by means of a specific affinity between Con A and mannose. For this purpose, LOx was modified with mannose residues covalently by treating with an excess amount of 4-isothiocyanatephenyl-α-D-mannopyranose. By this treatment LOx was tagged with several residues of mannose. Con A and the mannose-modified LOx were deposited on the surface of a platinum electrode alternately, by immersing the electrode in the solutions of Con A and enzyme. It was found that Con A/LOx multilayers are formed in this simple procedure. A gravimetric study using a quartz-crystal microbalance and a spectrophotometric study also suggested a formation of the Con A/LOx multilayers. The Con A/LOx multilayer-modified electrodes exhibited an amperometric response to 10^-6-3×10^-2 M L-lactate, the size of the output current being dependent on the number of the enzyme layers.

Chemical Sensors published new progress about 96345-79-8. 96345-79-8 belongs to alcohols-buliding-blocks, auxiliary class Sugar Units,Gal and Man, name is (2R,3S,4S,5S,6R)-2-(Hydroxymethyl)-6-(4-isothiocyanatophenoxy)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C13H15NO6S, Related Products of alcohols-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Tarif, Ejaj published the artcileDynamics at the non-ionic micelle/water interface: Impact of linkage substitution, Related Products of alcohols-buliding-blocks, the publication is Journal of Chemical Physics (2019), 151(15), 154902/1-154902/9, database is CAplus and MEDLINE.

The impact of atom substitution on the glycoside linkage bridging the head and the tail parts in a nonionic surfactant mol. on aqueous dynamics of the resultant micellar solutions has been explored, employing time-resolved fluorescence and dielec. relaxation (DR) measurements. We have utilized n-octyl-β-D-glucopyranoside (OG) and n-octyl-β-D-thioglucopyranoside (OTG) as nonionic surfactants where the oxygen atom in the glucopyranoside unit is substituted by a sulfur atom. The substitution impact is immediately reflected in the dynamic light scattering measurements of aqueous solutions where the estimated size of the OTG micelles is found to be approx. four times larger than the OG micelles. Steady state spectral features obtained by using a fluorescent probe solute, coumarin 153 (C153), in these micellar solutions are quite similar and indicate locations of the solute at the micelle/water interface for both the surfactants. Interestingly, significant differences in the rotational and solvation dynamics of C153 in these two micellar solutions have been registered. The corresponding DR measurements do not indicate any signature of relaxation typical of bound water. The absence of bound water is further supported by the differential scanning calorimetric measurements. However, the typical slow solvation time scale for aqueous micellar solutions has been observed for these surfactants. Fluctuations in the solute-interface interaction energy due to the solute motion has been argued to be the origin for this slow solvation component as DR measurements do not indicate the presence of qual. similar relaxation time scale in the medium. (c) 2019 American Institute of Physics.

Journal of Chemical Physics published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C6H8O3, Related Products of alcohols-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Kawabata, Takeo published the artcileA Catalytic One-Step Process for the Chemo- and Regioselective Acylation of Monosaccharides, SDS of cas: 85618-21-9, the publication is Journal of the American Chemical Society (2007), 129(42), 12890-12895, database is CAplus and MEDLINE.

An organo-catalytic method for the chemo- and regioselective acylation of monosaccharides has been developed. Treatment of octyl β-D-glucopyranoside with isobutyric anhydride in the presence of 10 mol % of a C₂-sym. chiral 4-pyrrolidinopyridine catalyst at -50 °C gave the 4-O-isobutyryl derivative as the sole product in 98% yield. Thus, chemoselective acylation, favoring a secondary hydroxyl group in the presence of a free primary hydroxyl group, and regioselective acylation, favoring one of three secondary hydroxyl groups, took place with perfect selectivity. A competitive acylation between octyl β-D-glucopyranoside and a primary alc. (2-phenylethanol) with 1.1 equiv of isobutyric anhydride in the presence of 4-pyrrolidinopyridine catalyst gave the 4-O-isobutyrate of octyl β-D-glucopyranoside with 99% regioselectivity in 98% yield, which indicates that acylation of the secondary hydroxyl group at C(4) of the carbohydrate proceeds in an accelerative manner. A possible mechanism, involving multiple hydrogen-bonding between 4-pyrrolidinopyridine catalyst and the monosaccharide, is proposed for the chemo- and regioselective acylation.

Journal of the American Chemical Society published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C14H28O5S, SDS of cas: 85618-21-9.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Ueda, Yoshihiro published the artcileFunctional Group Tolerance in Organo-Catalytic Regioselective Acylation of Carbohydrates, SDS of cas: 85618-21-9, the publication is Journal of Organic Chemistry (2009), 74(22), 8802-8805, database is CAplus and MEDLINE.

Organo-catalytic regioselective acylation of mono- and disaccharides with various functionalized acid anhydrides has been developed. Acylation of octyl β-D-glucopyranoside with acid anhydrides derived from α-amino acids, cinnamic acid, and gallic acid took place at C(4)-OH with 67-94% regioselectivity in the presence of catalyst I. Regioselective acylation of disaccharides with functionalized acid anhydrides was also achieved with 78-94% selectivity. Especially, a disaccharide with seven free hydroxy groups (X = OH, R’ = H) underwent acylation at C(4)-OH with 78% regioselectivity in the presence of I. Thus, functional group tolerance in the regioselective acylation catalyzed by I was found to be high.

Journal of Organic Chemistry published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C9H6BrNO, SDS of cas: 85618-21-9.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Carnero Ruiz, C. published the artcileCharacterization of mixed nonionic surfactants n-octyl-β-D-thioglucoside and octaethylene-glycol monododecyl ether: Micellization and microstructure, Computed Properties of 85618-21-9, the publication is Journal of Colloid and Interface Science (2011), 361(1), 178-185, database is CAplus and MEDLINE.

Mixed micelles of n-octyl-β-D-thioglucoside (OTG) and octaethylene-glycol monododecyl ether (C₁₂E₈), two nonionic surfactants belonging to the alkyl glucosides and polyoxyethylene alkyl ether families, resp., were studied by using light scattering and fluorescence probe techniques. From the determination of the critical micelle concentration (cmc), by the well-established pyrene 1:3 ratio method, the mixed system behaves ideally, the micellization process being clearly controlled by the ethoxylated surfactant. The micellar hydrodynamic radius as a function of temperature, composition and concentration was obtained by dynamic light scattering measurements. The micellar size increases with temperature, this growth being more pronounced as the relative proportion of the ethoxylated surfactant was increased. The behavior of the micellar size with the total surfactant concentration also is dependent on temperature and composition The clouding temperature, characteristic of the ethoxylated surfactants, was increased with the addition of the sugar surfactant. Lastly, possible structural changes in the micellar palisade layer were examined by steady-state fluorescence anisotropy in conjunction with time-resolved fluorescence studies with the hydrophobic probe coumarin 6 (C6). The participation of the ethoxylated surfactant induces a slightly more polar palisade layer, whereas the probe carries out a faster rotational reorientation as a result of a less compact environment. All these observations were attributed to the different structure of the head groups of both surfactants and, as a consequence, to their different hydration.

Journal of Colloid and Interface Science published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C14H28O5S, Computed Properties of 85618-21-9.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Hierrezuelo, J. M. published the artcileOn the Urea Action Mechanism: A Comparative Study on the Self-Assembly of Two Sugar-Based Surfactants, Synthetic Route of 85618-21-9, the publication is Journal of Physical Chemistry B (2009), 113(20), 7178-7187, database is CAplus and MEDLINE.

Studies on the effect of urea on micelle formation and structure of n-octyl-β-D-thioglucoside (OTG) and N-decanoyl-N-methylglucamide (MEGA-10) were carried out by using the steady-state and time-resolved fluorescence techniques, together with combined static and dynamic light scattering measurements. A similar increase in the critical micelle concentration with the urea addition was observed for both surfactants. This behavior was attributed to a rise in the solubility of hydrocarbon tails and the increase of solvation of the headgroup of the surfactants in the presence of urea. Structural studies mainly based on the anal. of the hydrodynamic radius and aggregation number of micelles revealed that urea induces changes much more significant on micelles of OTG. Particularly, it was found that, whereas the surface area per headgroup of OTG increases with the urea concentration, it does decrease in the case of MEGA-10. This fact suggests that different action mechanisms operate for both surfactants. Accordingly, investigations on the micellar microstructure based on the study of microenvironmental properties such as micropolarity and microviscosity also indicated a more pronounced effect in the case of OTG. Although changes were not observed in the hydrophobic inner region of both micellar systems, a significant increase of polarity and viscosity in the micellar interface of OTG suggests a direct participation of urea in the micellar solvation layer. The differences between the observed behaviors for both micellar systems were interpreted on the basis of two features: the weaker hydration and greater rigidity of the OTG headgroup as compared with MEGA-10.

Journal of Physical Chemistry B published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C14H28O5S, Synthetic Route of 85618-21-9.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Ruiz, Cristobal Carnero published the artcileSelf-assembly, surface activity and structure of n-octyl-β-D-thioglucopyranoside in ethylene glycol-water mixtures, SDS of cas: 85618-21-9, the publication is International Journal of Molecular Sciences (2013), 3228-3253, database is CAplus and MEDLINE.

The effect of the addition of ethylene glycol (EG) on the interfacial adsorption and micellar properties of the alkylglucoside surfactant n-octyl-β-D-thioglucopyranoside (OTG) has been investigated. Critical micelle concentrations (cmc) upon EG addition were obtained by both surface tension measurements and the pyrene 1:3 ratio method. A systematic increase in the CMC induced by the presence of the co-solvent was observed This behavior was attributed to a reduction in the cohesive energy of the mixed solvent with respect to pure water, which favors an increase in the solubility of the surfactant with EG content. Static light scattering measurements revealed a decrease in the mean aggregation number of the OTG micelles with EG addition Moreover, dynamic light scattering data showed that the effect of the surfactant concentration on micellar size is also controlled by the content of the co-solvent in the system. Finally, the effect of EG addition on the microstructure of OTG micelles was investigated using the hydrophobic probe Coumarin 153 (C153). Time-resolved fluorescence anisotropy decay curves of the probe solubilized in micelles were analyzed using the two-step model. The results indicate a slight reduction of the average reorientation time of the probe mol. with increasing EG in the mixed solvent system, thereby suggesting a lesser compactness induced by the presence of the co-solvent.

International Journal of Molecular Sciences published new progress about 85618-21-9. 85618-21-9 belongs to alcohols-buliding-blocks, auxiliary class Tetrahydropyran,Chiral,sulfides,Alcohol, name is (2R,3S,4S,5R,6S)-2-(Hydroxymethyl)-6-(octylthio)tetrahydro-2H-pyran-3,4,5-triol, and the molecular formula is C14H28O5S, SDS of cas: 85618-21-9.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts