应用固-液相转移催1化方法合成肌醇磷酸脂

固-液相转移催化方法已成功地应用于各种肌醇磷酸脂的合成.在固- 液相转移催化条件下,肌醇衍生物O-烷基化的选择性得到了有效的改进;而在固- 液相转移催化条件下的atheron-todd反应,为肌醇衍生物的磷酰化提供了一个良好的新方法.     

Determination of myo-inositol (free and bound as phosphatidylinositol) in infant formula and adult nutritionals by liquid chromatography/pulsed amperometry with column switching: first action 2011.18

Myo-inositol is a 6-carbon cyclic polyalcohol also known as meso-inositol, meat sugar, inosite, and i-inositol. It occurs in nature in both free (myo-inositol) and bound (inositol phosphates and phosphatidylinositol) forms. For the determination of free myo-inositol, samples are mixed with dilute hydrochloric acid to extract myo-inositol and precipitate proteins, diluted with water, and filtered. For the determination of myo-inositol bound as phosphatidylinositol, samples are extracted with chloroform, isolated from other fats with silica SPE cartridges, and hydrolyzed with concentrated acid to free myo-inositol. Prepared samples are first injected onto a Dionex CarboPac PA1 column, which separates myo-inositol from other late-eluting carbohydrates. After column switching, myo-inositol is further separated on a CarboPac MA1 column using a 0.12% sodium hydroxide mobile phase; strongly retained carbohydrates are eluted from the PA1 column with a 3% sodium hydroxide mobile phase. Eluant from the CarboPac MA1 analytical column passes through an electrochemical detector cell where myo-inositol is detected by pulsed amperometry using a gold electrode. The method showed appropriate performance characteristics versus selected established standard method performance requirement parameters for the determination of myo-inositol: linear response; repeatability (RSDr) of 2%; and intermediate precision (RSDir) of 2.5%. Instrument LOD and LOQ were 0.0004 and 0.0013 mg/100 mL, respectively, and correspond to a free myo-inositol quantitation limit of 0.026 mg/100 g and a phosphatidylinositol quantitation limit of 0.016 mg/100 g. Correlation with the reference microbiological assay was good. The proposed method has been accepted by the Expert Review Panel as an AOAC First Action Method, suitable for the routine determination of myo-inositol in infant formula and adult nutritionals.     

Determination of myo-inositol phosphates in food samples by flow injection-capillary zone electrophoresis

A capillary electrophoresis (CE) method with indirect photometric detection was developed to identify and quantify myo-inositol phosphates in food samples. A flow-injection (FI) system including a micro-column containing anionic exchange resin was used for the solid-phase extraction of the myo-inositol phosphates with a view to their preconcentration. The FI system was automatically coupled to CE equipment via a mechanical interface. The overall analysis time was shortened by incorporating an FI system for myo-inositol hexakisphosphate monitoring. The limit of detection for myo-inositol phosphates as determined by FI-CE ranged from 11 to 26 micromol/L and the coefficient of variation from 3.9 to 5.0%. On the other hand, the limit of detection and coefficient of variation for myo-inositol hexakisphosphate as monitored by the FI system were 75 micromol/L and 2.9%, respectively. The proposed method was successfully applied to a variety of food samples with recoveries ranging from 96.0 to 107.7% and the precision from 3.9 to 7.9%. Based on the results, the content of myo-inositol hexakisphosphate in nuts was two or three times higher than that in legumes.     

Total synthesis of optically active myo-inositol 1,4,5-tris(phosphate)

Optically active myo-inositol 1,4,5-tris(phosphate) has been synthesized starting from myo-inositol.     

Simultaneous determination of myo-inositol and scyllo-inositol by MEKC as a rapid monitoring tool for inositol levels

A simple and rapid MEKC method was developed for the simultaneous determination of myo-inositol, scyllo-inositol, and glucose. Prior to electrophoretic separation, the nonfluorescent inositols and glucose were derivatized by N-methylisatoic anhydride at 25 degrees C for 10 min so that they could be detected by a fluorescence detector during separation. The good separation with high efficiency by MEKC was achieved in 13 min with a glycine buffer containing SDS and PEG 4000. Several parameters affecting the separation were studied, including the pH of BGE, the concentrations of glycine, SDS, and PEG 4000, and the applied voltage. Using glycerol as an internal standard, the linear ranges of the method for myo-inositol, scyllo-inositol, and glucose were 0.03-10, 0.01-5, and 0.05-20 mM; the concentration LODs of myo-inositol, scyllo-inositol, and glucose were 0.020, 0.0078, and 0.026 mM, respectively. The method was applied to analyze extracellular myo-inositol and glucose in the microdialysates from rat brain cortex of ischemia animal model and intracellular myo-inositol and scyllo-inositol in the rat brain extract.     

Regioselective hydrolysis of myo-inositol 1,3,5-orthobenzoate via a 1,2-bridged 2'-phenyl-1',3'-dioxolan-2'-ylium ion provides a rapid route to the anticancer agent Ins(1,3,4,5,6)P5

Acid hydrolysis of myo-inositol 1,3,5-orthobenzoate leads regioselectively to 2-O-benzoyl-myo-inositol via a 1,2-bridged 2'-phenyl-1',3'-dioxolan-2'-ylium ion observed by 1H and 13C NMR spectroscopy, providing the precursor for a highly efficient route to the anticancer agent myo-inositol 1,3,4,5,6-pentakisphosphate.     

肌醇在碱金属氯化物溶液中的体积性质

使用精密数字密度计测定了298.15和308.15 K肌醇在不同浓度的LiCl-H2O、NaCl-H2O或KCl-H2O溶液中的密度, 计算了肌醇的表观摩尔体积Vφ和极限偏摩尔体积Vθφ , 得到了其由纯水溶剂转移至混合溶剂中的迁移偏摩尔体积⊿trsVθ椎 .结果表明, LiCl, NaCl和KCl在溶液中对肌醇的体积性质影响显著, 极限偏摩尔体积Vθφ和极限迁移偏摩尔体积⊿trsVθφ都随盐浓度的增大而增加;温度对肌醇的极限偏摩尔体积和极限迁移偏摩尔体积只有轻微影响. 从分子-离子间的相互作用角度对实验结果进行了讨论.     

Gibbs energies of interaction of the CH2 and CHOH groups from freezing point data for aqueous binary mixtures of D-mannitol,myo-inositol,and cyclohexanol

Freezing temperatures of dilute aqueous solutions of D-mannitol, myo-inositol, D-mannitol + myo-inositol, D-mannitol + cyclohexanol, and myo-inositol + cyclohexanol have been measured over the concentration range 0.1 to 1.0 mol-kg^–1. These data yield pairwise molecular Gibbs energies of interaction which have been corrected to 25°C and treated according to the Savage-Wood additivity principle to give pairwise functional group Gibbs energies of interaction for CH₂/CH₂, CH₂/COOH, and CHOH/CHOH. Anomalous behavior of some systems is discussed in terms of the interactions.     

A definitive synthesis of D-myo-inositol 1,4,5,6-tetrakisphosphate and its enantiomer D-myo-inositol 3,4,5,6-tetrakisphosphate from a novel butane-2,3-diacetal-protected inositol

New and rapid syntheses of the enantiomeric intracellular signalling molecules d-myo-inositol 1,4,5,6-tetrakisphosphate (1 a) and D-myo-inositol 3,4,5,6-tetrakisphosphate (1 b) are described. The synthetic strategy employs the novel butane-2,3-diacetal-protected (BDA-protected) myo-inositol (+/-)-3 ab, directly accessible from myo-inositol on a large scale, and an optical resolution with diastereoisomeric (R)-(-)-acetylmandelate esters. The X-ray crystal structure of (+/-)-4, an unusual side product of acid-catalysed reaction of myo-inositol with butanedione is also presented, and the absolute configurations of 1 a and 1 b are definitively assigned by conversion of key precursors into (+)-bornesitol and L-iditol hexaacetate, respectively. Biological activity of synthetic 1 b was confirmed in comparison with the natural polyphosphate.     

Anion-exchange high-performance liquid chromatography with post-column detection for the analysis of phytic acid and other inositol phosphates

The use of gradient anion-exchange HPLC, with a simple post-column detection system, is described for the separation of myo-inositol phosphates, including "phytic acid" (myo-inositol hexaphosphate). Hexa-, penta-, tetra-, tri- and diphosphate members of this homologous series are clearly resolved within 30 min. This method should facilitate analysis and quantitation of "phytic acid" and other inositol phosphates in plant, food, and soil samples.     

肌醇在纯水和卤化钠水溶液中稀释过程的热力学性质

应用微量热法测定了298.15 K时肌醇在纯水和卤化钠水溶液中的稀释焓, 根据McMillan-Mayer理论, 计算了肌醇在溶液中的二到四阶焓相互作用系数. 结果表明, 肌醇在卤化钠溶液中的焓对相互作用系数h2均为负值, 并且随着卤素阴离子半径的增大, h2的绝对值呈增大趋势.     

Synthesis of D-myo-inositol 1,3,4,5-tetrakisphosphate

Chemical synthesis of D-myo-inositol 1,3,4,5-tetrakisphosphate was accomplished starting from myo-inositol.     

Synthesis of the aminocyclitol units of (-)-hygromycin A and methoxyhygromycin from myo-inositol

Concise and efficient syntheses of the aminocyclitol cores of hygromycin A (HMA) and methoxyhygromycin (MHM) have been achieved starting from readily available myo-inositol. Reductive cleavage of myo-inositol orthoformate to the corresponding 1,3-acetal, stereospecific introduction of the amino group via the azide, and resolution of a racemic cyclitol derivative as its diastereomeric mandelate esters are the key steps in the synthesis. Synthesis of the aminocyclitol core of hygromycin A involved chromatography in half of the total number of steps, and the aminocyclitol core of methoxyhygromycin involved only one chromatography.     

Improvement of nerve conduction velocity in mutant diabetic mice by aldose reductase inhibitor without affecting nerve myo-inositol content

The sciatic motor nerve conduction velocity of mutant diabetic C57BL/Ks mice was significantly improved from 30.0 +/- 1.4 to 38.0 +/- 4.6 m/s by treatment with the aldose reductase inhibitor 1-[(beta-naphthyl)sulfonyl]hydantoin (30 mg/kg/d) for 2 weeks. The treatment, however, did not cause any significant change in myo-inositol concentration in the sciatic nerve. The results indicate that the ameliorating effect of the aldose reductase inhibitor on nerve conduction velocity in mutant diabetic mice is not due to alteration of myo-inositol content in the nerve.     

Interactions in aqueous nonelectrolyte systems. Gibbs energy of interaction of the ether group with the hydroxyl group and the amide group

Freezing temperatures of dilute aqueous solutions of equimolar mixtures of 1,3,5-trioxane with myo-inositol, d-mannitol, cyclohexanol, formamide, and acetamide, and 1,4-dioxane with myo-inositol, d-mannitol, formamide, and acetamide have been measured. These data yield pairwise Gibbs energies of interactions between the molecules in an aqueous solution. Using the group additivity principle, the results also yield the pairwise functional group Gibbs energies of interaction for the ether group with the hydroxyl and amide group. These results have been combined with all available data from the literature to yield the Gibbs energy and enthalpy of interaction of amides, ethers, alcohols, and saccharides in aqueous solution.To whom correspondence should be addressed.     

Fluorescent probe: complexation of Fe3+ with the myo-inositol 1,2,3-trisphosphate motif

Natural myo-inositol phosphate antioxidants containing the 1,2,3-trisphosphate motif bind Fe(3+) in the unstable penta-axial conformation.     

Diffusion of polyols in aqueous solution

The diffusion coefficients of aqueous solutions of the polyols CH₂OH-(CHOH)₄-CH₂OH (dulcitol, sorbitol, and myo-inositol) have been determinated using the Gouy interferometric method. Viscosity and density measurements have been carried out at the same temperature and concentration range for these and for mannitol. The concentration dependence of the diffusion coefficients are discussed in terms of solute-solute interactions with the help of thermodynamic literature data. Among the studied polyols, only dulcitol and myo-inositol exhibit a strong evidence for solute-solute interaction, whereas the other shows a preferential interaction with the solvent.     

Molecular evolution using intramolecular acyl migration on myo-inositol benzoates with thermodynamic and kinetic selectors

A molecular evolution model was successfully demonstrated by combining the intramolecular acyl migration on inositol tribenzoates and boron selectors. The addition of boric acid to 12 members of DCL (dynamic combinatorial library) induced the dramatic amplification of myo-I(2,4,6)Bz(3) (1) with up to 94 % under thermodynamic (see Figure 1 c) control while a portion of phenyl boronic acid caused two significant different distributions: under kinetic control, the pre-equilibrium of DCL shifted to induce the exclusive amplification of 1,4,6-tribenzoyl myo-inositol (7) with decrease of other members up to 82 % from the mixture (see Figure 2 b), and changed gradually to form 2,4,6-tribenzoyl myo-inositol (1) with up to 96 % under thermodynamic control (Figure 2 c).     

1H NMR titrations of hydroxy protons in aqueous solution as a method of investigation of intramolecular hydrogen-bonding in phosphorylated compounds: examples of myo-inositol 2-phosphate and myo-inositol 1,2,6-tris(phosphates)

1H NMR hydroxy proton titration experiments for myo-inositol 2-phosphate and myo-inositol 1,2,6-tris(phosphates) in aqueous solution are presented to demonstrate that by following OH signals versus pH, evidence can be brought for HB interaction between the hydroxyl and phosphate groups. The chemical shifts of the OH protons vicinal to phosphate groups appear deshielded by ca. 2.5 ppm with regard to those two centers removed from the phosphates. Remarkably, the deshielded protons are only present when their neighboring phosphate groups are fully deprotonated but persist until high pHs. From these results, C-OH...2-O3P-O type I, C-HO...-HO3P-O type II and C-OH...-HO3P-O type III hydrogen bonds are evidenced and discussed.     

Isolation and identification of myo-inositol crystals from dragon fruit (Hylocereus polyrhizus)

Crystals isolated from Hylocereus polyrhizus were analyzed using four different approaches--X-ray Crystallography, High Performance Liquid Chromatography (HPLC), Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and Nuclear Magnetic Resonance (NMR) and identified as myo-inositol. The X-ray crystallography analysis showed that the unit-cell parameters were: a = 6.6226 (3) ?, b = 12.0462 (5) ?, c = 18.8942 (8) ?, α = 90.00, β = 93.98, δ = 90.00. The purity of the crystals were checked using HPLC, whereupon a clean single peak was obtained at 4.8 min with a peak area of 41232 μV*s. The LC-MS/MS technique, which is highly sensitive and selective, was used to provide a comparison of the isolated crystals with a myo-inositol standard where the results gave an identical match for both precursor and product ions. NMR was employed to confirm the molecular structure and conformation of the crystals, and the results were in agreement with the earlier results in this study. The discovery of myo-inositol crystals in substantial amount in H. polyrhizus has thus far not been reported and this is an important finding which will increase the marketability and importance of H. polyrhizus as a crop with a wide array of health properties.