The synthesis of l-gulose and l-xylose from d-gluconolactone

Yang, Wen‐Bin; Patil, Sachindra S.; Tsai, Cheng-Hsin; Lin, Chun‐Chi; Fang, Jim‐Min

doi:10.1016/s0040-4020(01)01146-2

Cited by 28 publications

(13 citation statements)

References 35 publications

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“…The synthesis of important intermediate 19 ( A in Scheme ), which is a precursor for guanidinylation, and total synthesis of 6 are shown in Scheme . Deacetylation of 16 with KCN in ethanol gave 17 without epimerization at the C‐9 position, and then deprotection of the acetonide in the presence of acid‐sensitive TBS ethers was carried out with SnCl 2 ⋅ 2 H 2 O in dichloromethane23 to give diol 18 in a moderate yield along with about 20 % of starting material 17 . Cleavage of the diol with NaIO 4 and subsequent treatment with PPTS and trimethyl orthoformate provided the intramolecular acetal 19 .…”

Section: Total Synthesis Of 5‐deoxytetodotoxinmentioning

confidence: 99%

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO₄ and LiNi_1/2Mn_1/2O₂

et al. 2014

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The present review reports the characterization and control of interfacial processes occurring on olivine LiFePO(4) and layered LiNi(1/2) Mn(1/2)O(2), standing here as model compounds, during storage and electrochemical cycling. The formation and evolution of the interphase created by decomposition of the electrolyte is investigated by using spectroscopic tools such as magic-angle-spinning nuclear magnetic resonance ((7)Li,(19)F and (31)P) and electron energy loss spectroscopy, in parallel to X-ray photoelectron spectroscopy, to quantitatively describe the interphase and unravel its architecture. The influence of the pristine surface chemistry of the active material is carefully examined. The importance of the chemical history of the surface of the electrode material before any electrochemical cycling and the strong correlation between interface phenomena, the formation/evolution of an interphase, and the electrochemical behavior appear clearly from the use of these combined characterization probes. This approach allows identifying interface aging and failure mechanisms. Different types of surface modifications are then investigated, such as intrinsic modifications upon aging in air or methods based on the use of additives in the electrolyte or carbon coatings on the surface of the active materials. In each case, the species detected on the surface of the materials during storage and cycling are correlated with the electrochemical performance of the modified positive electrodes.

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Section: Total Synthesis Of 5‐deoxytetodotoxinmentioning

confidence: 99%

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO₄ and LiNi_1/2Mn_1/2O₂

et al. 2014

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“…To cleave the 1,2‐glycol protected as an acetonide, deprotection of the acetonide was attempted. Although the selective deprotection in the presence of acid‐sensitive protective groups such as siloxy groups was difficult, we fortunately found that 17 was treated with SnCl 2 ⋅ 2 H 2 O in CH 2 Cl 2 27 to give 1,2‐diol 18 in 66 % yield along with the recovered starting material 17 in 15 % yield. Cleavage of the 1,2‐diol of 18 with sodium periodate and subsequent treatment with PPTS and triethyl orthoformate in ethanol provided intramolecular acetal 19 as a single diastereomer 28.…”

Section: Methodsmentioning

confidence: 99%

Total Synthesis of Chiriquitoxin, an Analogue of Tetrodotoxin Isolated from the Skin of a Dart Frog

Adachi

Imazu

Sakakibara

et al. 2014

Chemistry A European J

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The first total synthesis of chiriquitoxin, the most structurally complex analogue of tetrodotoxin isolated from a Costa Rican dart frog, has been accomplished from a newly designed intermediate for a variety of tetrodotoxin derivatives. The synthesis includes the third total synthesis of tetrodotoxin in this laboratory, and its intermediate was transformed into chiriquitoxin by a stereocontrolled aldol reaction with a D-camphor-derived lactone for installation of the unique side chain, and a new deprotection of methylthiomethyl (MTM) ether by using a Pummerer rearrangement.

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“…In the latter study, amplification of histone methyltransferase, SETDB1, that mediates H3K9 methylation, was found to accelerate melanoma formation in zebrafish indicating the oncogenic potential of this methyltransferase (19). SETDB1, also called ESET, belongs to the family of SET domain histone methyltransferases (Suv39H, EZH2 and G9a) (20,21), which contain a 150-amino acid motif that is highly conserved and implicated in the modulation of chromatin structure. This SET domain characterizes proteins that modulate transcriptionally active or repressed chromatin states through chromatin remodelling activities (22).…”

Section: Introductionmentioning

confidence: 97%

High‐frequency p16^INK^4A promoter methylation is associated with histone methyltransferase SETDB1 expression in sporadic cutaneous melanoma

Kostaki

Manona

Stavraka

et al. 2014

Experimental Dermatology

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Epigenetic mechanisms participate in melanoma development and progression. The effect of histone modifications and their catalysing enzymes over euchromatic promoter DNA methylation in melanoma remains unclear. This study investigated the potential association of p16(INK) (4A) promoter methylation with histone methyltransferase SETDB1 expression in Greek patients with sporadic melanoma and their correlation with clinicopathological characteristics. Promoter methylation was detected by methylation-specific PCR in 100 peripheral blood samples and 58 melanoma tissues from the same patients. Cell proliferation (Ki-67 index), p16(INK) (4A) and SETDB1 expression were evaluated by immunohistochemistry. High-frequency promoter methylation (25.86%) was observed in tissue samples and correlated with increased cell proliferation (P = 0.0514). p16(INK) (4A) promoter methylation was higher in vertical growth-phase (60%) melanomas than in radial (40%, P = 0.063) and those displaying epidermal involvement (P = 0.046). Importantly, p16(INK) (4A) methylation correlated with increased melanoma thickness according to Breslow index (P = 0.0495) and marginally with increased Clark level (I/II vs III/IV/V, P = 0.070). Low (1-30%) p16(INK) (4A) expression was detected at the majority (19 of 54) of melanoma cases (35.19%), being marginally correlated with tumor lymphocytic infiltration (P = 0.078). SETDB1 nuclear immunoreactivity was observed in 47 of 57 (82.46%) cases, whereas 27 of 57 (47.37%) showed cytoplasmic immunoexpression. Cytoplasmic SETDB1 expression correlated with higher frequency of p16(INK) (4A) methylation and p16(INK) (4A) expression (P = 0.033, P = 0.011, respectively). Increased nuclear SETDB1 levels were associated with higher mitotic count (0-5/mm(2) vs >5/mm(2) , P = 0.0869), advanced Clark level (III-V, P = 0.0380), epidermal involvement (P = 0.0331) and the non-chronic sun exposure-associated melanoma type (P = 0.0664). Our data demonstrate for the first time the association of histone methyltransferase SETDB1 with frequent methylation of the euchromatic p16(INK) (4A) promoter and several prognostic parameters in melanomas.

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The synthesis of l-gulose and l-xylose from d-gluconolactone

Cited by 28 publications

References 35 publications

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO₄ and LiNi_1/2Mn_1/2O₂

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO₄ and LiNi_1/2Mn_1/2O₂

Total Synthesis of Chiriquitoxin, an Analogue of Tetrodotoxin Isolated from the Skin of a Dart Frog

High‐frequency p16^INK^4A promoter methylation is associated with histone methyltransferase SETDB1 expression in sporadic cutaneous melanoma

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The synthesis of l-gulose and l-xylose from d-gluconolactone

Cited by 28 publications

References 35 publications

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO4 and LiNi1/2Mn1/2O2

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO4 and LiNi1/2Mn1/2O2

Total Synthesis of Chiriquitoxin, an Analogue of Tetrodotoxin Isolated from the Skin of a Dart Frog

High‐frequency p16INK4A promoter methylation is associated with histone methyltransferase SETDB1 expression in sporadic cutaneous melanoma

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Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO₄ and LiNi_1/2Mn_1/2O₂

Interphase Evolution at Two Promising Electrode Materials for Li‐Ion Batteries: LiFePO₄ and LiNi_1/2Mn_1/2O₂

High‐frequency p16^INK^4A promoter methylation is associated with histone methyltransferase SETDB1 expression in sporadic cutaneous melanoma